2016-03-18 21:00:23

by Josh Triplett

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:
> On Thu, Feb 25, 2016 at 04:13:11PM +1100, Ross Green wrote:
> > On Wed, Feb 24, 2016 at 8:28 AM, Ross Green <[email protected]> wrote:
> > > On Wed, Feb 24, 2016 at 7:55 AM, Paul E. McKenney
> > > <[email protected]> wrote:
>
> [ . . . ]
>
> > >> Still working on getting decent traces...
>
> And I might have succeeded, see below.
>
> > >>
> > >> Thanx, Paul
> > >>
> > >
> > > G'day all,
> > >
> > > Here is another dmesg output for 4.5-rc5 showing another rcu_preempt stall.
> > > This one appeared after only a day of running. CONFIG_DEBUG_TIMING is
> > > turned on, but can't see any output that shows from this.
> > >
> > > Again testing as before,
> > >
> > > Boot, run a series of small benchmarks, then just let the system be
> > > and idle away.
> > >
> > > I notice in the stack trace there is mention of hrtimer_run_queues and
> > > hrtimer_interrupt.
> > >
> > > Anyway, leave this for a few more eyes to look at.
> > >
> > > Open to any other suggestions of things to test.
> > >
> > > Regards,
> > >
> > > Ross Green
> >
> >
> > G'day Paul,
> >
> > I left the pandaboard running and captured another stall.
> >
> > the attachment is the dmesg output.
> >
> > Again there is no apparent output from any CONFIG_DEBUG_TIMING so I
> > assume there is nothing happening there.
>
> I agree, looks like this is not due to time skew.
>
> > I just saw the updates for 4.6 RCU code.
> > Is the patch in [PATCH tip/core/rcu 04/13] valid here?
>
> I doubt that it will help, but you never know.
>
> > do you want me try the new patch set with this configuration?
>
> Even better would be to try Daniel Wagner's swait patchset. I have
> attached them in UNIX mbox format, or you can get them from the
> -tip tree.
>
> And I -finally- got some tracing that -might- be useful. The dmesg, all
> 67MB of it, is here:
>
> http://www.rdrop.com/~paulmck/submission/console.2016.02.23a.log
>
> This failure mode is less likely to happen, and looks a bit different
> than the ones that I was seeing before enabling tracing. Then, an
> additional wakeup would actually wake the task up. In contrast, with
> tracing enabled, the RCU grace-period kthread goes into "teenager mode",
> refusing to wake up despite repeated attempts. However, this might
> be a side-effect of the ftrace dump.
>
> On line 525,132, we see that the rcu_preempt grace-period kthread has
> been starved for 1,188,154 jiffies, or about 20 minutes. This seems
> unlikely... The kthread is waiting for no more than a three-jiffy
> timeout ("RCU_GP_WAIT_FQS(3)") and is in TASK_INTERRUPTIBLE state
> ("0x1").

We're seeing a similar stall (~60 seconds) on an x86 development system
here. Any luck tracking down the cause of this? If not, any
suggestions for traces that might be helpful?

- Josh Triplett


2016-03-18 23:56:53

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Fri, Mar 18, 2016 at 02:00:11PM -0700, Josh Triplett wrote:
> On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:
> > On Thu, Feb 25, 2016 at 04:13:11PM +1100, Ross Green wrote:
> > > On Wed, Feb 24, 2016 at 8:28 AM, Ross Green <[email protected]> wrote:
> > > > On Wed, Feb 24, 2016 at 7:55 AM, Paul E. McKenney
> > > > <[email protected]> wrote:
> >
> > [ . . . ]
> >
> > > >> Still working on getting decent traces...
> >
> > And I might have succeeded, see below.
> >
> > > >>
> > > >> Thanx, Paul
> > > >>
> > > >
> > > > G'day all,
> > > >
> > > > Here is another dmesg output for 4.5-rc5 showing another rcu_preempt stall.
> > > > This one appeared after only a day of running. CONFIG_DEBUG_TIMING is
> > > > turned on, but can't see any output that shows from this.
> > > >
> > > > Again testing as before,
> > > >
> > > > Boot, run a series of small benchmarks, then just let the system be
> > > > and idle away.
> > > >
> > > > I notice in the stack trace there is mention of hrtimer_run_queues and
> > > > hrtimer_interrupt.
> > > >
> > > > Anyway, leave this for a few more eyes to look at.
> > > >
> > > > Open to any other suggestions of things to test.
> > > >
> > > > Regards,
> > > >
> > > > Ross Green
> > >
> > >
> > > G'day Paul,
> > >
> > > I left the pandaboard running and captured another stall.
> > >
> > > the attachment is the dmesg output.
> > >
> > > Again there is no apparent output from any CONFIG_DEBUG_TIMING so I
> > > assume there is nothing happening there.
> >
> > I agree, looks like this is not due to time skew.
> >
> > > I just saw the updates for 4.6 RCU code.
> > > Is the patch in [PATCH tip/core/rcu 04/13] valid here?
> >
> > I doubt that it will help, but you never know.
> >
> > > do you want me try the new patch set with this configuration?
> >
> > Even better would be to try Daniel Wagner's swait patchset. I have
> > attached them in UNIX mbox format, or you can get them from the
> > -tip tree.
> >
> > And I -finally- got some tracing that -might- be useful. The dmesg, all
> > 67MB of it, is here:
> >
> > http://www.rdrop.com/~paulmck/submission/console.2016.02.23a.log
> >
> > This failure mode is less likely to happen, and looks a bit different
> > than the ones that I was seeing before enabling tracing. Then, an
> > additional wakeup would actually wake the task up. In contrast, with
> > tracing enabled, the RCU grace-period kthread goes into "teenager mode",
> > refusing to wake up despite repeated attempts. However, this might
> > be a side-effect of the ftrace dump.
> >
> > On line 525,132, we see that the rcu_preempt grace-period kthread has
> > been starved for 1,188,154 jiffies, or about 20 minutes. This seems
> > unlikely... The kthread is waiting for no more than a three-jiffy
> > timeout ("RCU_GP_WAIT_FQS(3)") and is in TASK_INTERRUPTIBLE state
> > ("0x1").
>
> We're seeing a similar stall (~60 seconds) on an x86 development system
> here. Any luck tracking down the cause of this? If not, any
> suggestions for traces that might be helpful?

The dmesg containing the stall, the kernel version, and the .config would
be helpful! Working on a torture test specific to this bug...

Thanx, Paul

2016-03-21 16:22:38

by Jacob Pan

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Fri, 18 Mar 2016 16:56:41 -0700
"Paul E. McKenney" <[email protected]> wrote:

> On Fri, Mar 18, 2016 at 02:00:11PM -0700, Josh Triplett wrote:
> > On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:
> > > On Thu, Feb 25, 2016 at 04:13:11PM +1100, Ross Green wrote:
> > > > On Wed, Feb 24, 2016 at 8:28 AM, Ross Green
> > > > <[email protected]> wrote:
> > > > > On Wed, Feb 24, 2016 at 7:55 AM, Paul E. McKenney
> > > > > <[email protected]> wrote:
> > >
> > > [ . . . ]
> > >
> > > > >> Still working on getting decent traces...
> > >
> > > And I might have succeeded, see below.
> > >
> > > > >>
> > > > >> Thanx,
> > > > >> Paul
> > > > >>
> > > > >
> > > > > G'day all,
> > > > >
> > > > > Here is another dmesg output for 4.5-rc5 showing another
> > > > > rcu_preempt stall. This one appeared after only a day of
> > > > > running. CONFIG_DEBUG_TIMING is turned on, but can't see any
> > > > > output that shows from this.
> > > > >
> > > > > Again testing as before,
> > > > >
> > > > > Boot, run a series of small benchmarks, then just let the
> > > > > system be and idle away.
> > > > >
> > > > > I notice in the stack trace there is mention of
> > > > > hrtimer_run_queues and hrtimer_interrupt.
> > > > >
> > > > > Anyway, leave this for a few more eyes to look at.
> > > > >
> > > > > Open to any other suggestions of things to test.
> > > > >
> > > > > Regards,
> > > > >
> > > > > Ross Green
> > > >
> > > >
> > > > G'day Paul,
> > > >
> > > > I left the pandaboard running and captured another stall.
> > > >
> > > > the attachment is the dmesg output.
> > > >
> > > > Again there is no apparent output from any CONFIG_DEBUG_TIMING
> > > > so I assume there is nothing happening there.
> > >
> > > I agree, looks like this is not due to time skew.
> > >
> > > > I just saw the updates for 4.6 RCU code.
> > > > Is the patch in [PATCH tip/core/rcu 04/13] valid here?
> > >
> > > I doubt that it will help, but you never know.
> > >
> > > > do you want me try the new patch set with this configuration?
> > >
> > > Even better would be to try Daniel Wagner's swait patchset. I
> > > have attached them in UNIX mbox format, or you can get them from
> > > the -tip tree.
> > >
> > > And I -finally- got some tracing that -might- be useful. The
> > > dmesg, all 67MB of it, is here:
> > >
> > > http://www.rdrop.com/~paulmck/submission/console.2016.02.23a.log
> > >
> > > This failure mode is less likely to happen, and looks a bit
> > > different than the ones that I was seeing before enabling
> > > tracing. Then, an additional wakeup would actually wake the task
> > > up. In contrast, with tracing enabled, the RCU grace-period
> > > kthread goes into "teenager mode", refusing to wake up despite
> > > repeated attempts. However, this might be a side-effect of the
> > > ftrace dump.
> > >
> > > On line 525,132, we see that the rcu_preempt grace-period kthread
> > > has been starved for 1,188,154 jiffies, or about 20 minutes.
> > > This seems unlikely... The kthread is waiting for no more than a
> > > three-jiffy timeout ("RCU_GP_WAIT_FQS(3)") and is in
> > > TASK_INTERRUPTIBLE state ("0x1").
> >
> > We're seeing a similar stall (~60 seconds) on an x86 development
> > system here. Any luck tracking down the cause of this? If not, any
> > suggestions for traces that might be helpful?
>
> The dmesg containing the stall, the kernel version, and the .config
> would be helpful! Working on a torture test specific to this bug...
>
> Thanx, Paul
>
+Reinette, she has the system that can reproduce the issue. I
believe she is having some other problems with it at the moment. But
the .config should be available. Version is v4.5.

2016-03-21 17:26:23

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 21, 2016 at 09:22:30AM -0700, Jacob Pan wrote:
> On Fri, 18 Mar 2016 16:56:41 -0700
> "Paul E. McKenney" <[email protected]> wrote:
> > On Fri, Mar 18, 2016 at 02:00:11PM -0700, Josh Triplett wrote:
> > > On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:

[ . . . ]

> > > We're seeing a similar stall (~60 seconds) on an x86 development
> > > system here. Any luck tracking down the cause of this? If not, any
> > > suggestions for traces that might be helpful?
> >
> > The dmesg containing the stall, the kernel version, and the .config
> > would be helpful! Working on a torture test specific to this bug...
> >
> > Thanx, Paul
> >
> +Reinette, she has the system that can reproduce the issue. I
> believe she is having some other problems with it at the moment. But
> the .config should be available. Version is v4.5.

A couple of additional questions:

1. Is the test running on bare metal or virtualized? If the
latter, what is the host?

2. Does the workload involve CPU hotplug?

3. Are you seeing things like this in dmesg?

"rcu_preempt kthread starved for 21033 jiffies"
"rcu_sched kthread starved for 32103 jiffies"
"rcu_bh kthread starved for 84031 jiffies"

If not, you are probably facing some other bug, and should
proceed debugging as described in Documentation/RCU/stallwarn.txt.

Thanx, Paul

2016-03-22 16:36:12

by Reinette Chatre

[permalink] [raw]
Subject: RE: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

Hi Paul,

On 2016-03-21, Paul E. McKenney wrote:
> On Mon, Mar 21, 2016 at 09:22:30AM -0700, Jacob Pan wrote:
>> On Fri, 18 Mar 2016 16:56:41 -0700
>> "Paul E. McKenney" <[email protected]> wrote:
>>> On Fri, Mar 18, 2016 at 02:00:11PM -0700, Josh Triplett wrote:
>>>> On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:
>
> [ . . . ]
>
>>>> We're seeing a similar stall (~60 seconds) on an x86 development
>>>> system here. Any luck tracking down the cause of this? If not, any
>>>> suggestions for traces that might be helpful?
>>>
>>> The dmesg containing the stall, the kernel version, and the .config
>>> would be helpful! Working on a torture test specific to this bug...
>>>
>>> Thanx, Paul
>>>
>> +Reinette, she has the system that can reproduce the issue. I
>> believe she is having some other problems with it at the moment. But
>> the .config should be available. Version is v4.5.
>
> A couple of additional questions:
>
> 1. Is the test running on bare metal or virtualized? If the
> latter, what is the host?

Bare metal.

> 2. Does the workload involve CPU hotplug?

No.

> 3. Are you seeing things like this in dmesg?
>
> "rcu_preempt kthread starved for 21033 jiffies"
> "rcu_sched kthread starved for 32103 jiffies"
> "rcu_bh kthread starved for 84031 jiffies"
>
> If not, you are probably facing some other bug, and should
> proceed debugging as described in Documentation/RCU/stallwarn.txt.

Below is a sample of what I see as captured with v4.5. The kernel configuration is attached.

[ 135.456197] INFO: rcu_preempt detected stalls on CPUs/tasks:
[ 135.457729] 3-...: (0 ticks this GP) idle=722/0/0 softirq=5532/5532 fqs=0
[ 135.459604] (detected by 2, t=60004 jiffies, g=2105, c=2104, q=165)
[ 135.461318] Task dump for CPU 3:
[ 135.461321] swapper/3 R running task 0 0 1 0x00200000
[ 135.461325] 00000078560040e5 ffff88017846fed0 ffffffff818af2cc ffff880100000000
[ 135.461330] 0000000600000003 ffff880178470000 ffff880072f32200 ffffffff822dcec0
[ 135.461334] ffff88017846c000 ffff88017846c000 ffff88017846fee0 ffffffff818af517
[ 135.461338] Call Trace:
[ 135.461345] [<ffffffff818af2cc>] ? cpuidle_enter_state+0xfc/0x310
[ 135.461349] [<ffffffff818af517>] ? cpuidle_enter+0x17/0x20
[ 135.461353] [<ffffffff811515aa>] ? call_cpuidle+0x2a/0x40
[ 135.461355] [<ffffffff8115197d>] ? cpu_startup_entry+0x28d/0x360
[ 135.461360] [<ffffffff8108c874>] ? start_secondary+0x114/0x140
[ 135.461365] rcu_preempt kthread starved for 60004 jiffies! g2105 c2104 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[ 135.463965] rcu_preempt S ffff88017844fd68 0 7 2 0x00000000
[ 135.463969] ffff88017844fd68 ffff88017dd8cc80 ffff880177ff0000 ffff880178443b80
[ 135.463973] ffff880178450000 ffff88017844fda0 ffff88017dd8cc80 ffff88017dd8cc80
[ 135.463977] 0000000000000003 ffff88017844fd80 ffffffff81ab031f 0000000100031504
[ 135.463981] Call Trace:
[ 135.463986] [<ffffffff81ab031f>] schedule+0x3f/0xa0
[ 135.463989] [<ffffffff81ab42d7>] schedule_timeout+0x127/0x270
[ 135.463993] [<ffffffff81171a50>] ? detach_if_pending+0x120/0x120
[ 135.463997] [<ffffffff8116da5d>] rcu_gp_kthread+0x6bd/0xa30
[ 135.464000] [<ffffffff81151390>] ? wake_atomic_t_function+0x70/0x70
[ 135.464003] [<ffffffff8116d3a0>] ? force_qs_rnp+0x1b0/0x1b0
[ 135.464006] [<ffffffff8112f846>] kthread+0xe6/0x100
[ 135.464009] [<ffffffff8112f760>] ? kthread_worker_fn+0x190/0x190
[ 135.464012] [<ffffffff81ab5c0f>] ret_from_fork+0x3f/0x70
[ 135.464015] [<ffffffff8112f760>] ? kthread_worker_fn+0x190/0x190

Thank you very much

Reinette



Attachments:
config (150.20 kB)
config

2016-03-22 17:40:18

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Tue, Mar 22, 2016 at 04:35:32PM +0000, Chatre, Reinette wrote:
> Hi Paul,

Hello, Reinette!

> On 2016-03-21, Paul E. McKenney wrote:
> > On Mon, Mar 21, 2016 at 09:22:30AM -0700, Jacob Pan wrote:
> >> On Fri, 18 Mar 2016 16:56:41 -0700
> >> "Paul E. McKenney" <[email protected]> wrote:
> >>> On Fri, Mar 18, 2016 at 02:00:11PM -0700, Josh Triplett wrote:
> >>>> On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:
> >
> > [ . . . ]
> >
> >>>> We're seeing a similar stall (~60 seconds) on an x86 development
> >>>> system here. Any luck tracking down the cause of this? If not, any
> >>>> suggestions for traces that might be helpful?
> >>>
> >>> The dmesg containing the stall, the kernel version, and the .config
> >>> would be helpful! Working on a torture test specific to this bug...

And thank you for the .config. Your kenrle version looks to be 4.5.0.

> >> +Reinette, she has the system that can reproduce the issue. I
> >> believe she is having some other problems with it at the moment. But
> >> the .config should be available. Version is v4.5.
> >
> > A couple of additional questions:
> >
> > 1. Is the test running on bare metal or virtualized? If the
> > latter, what is the host?
>
> Bare metal.

OK, you are ahead of me. Mine is virtualized.

> > 2. Does the workload involve CPU hotplug?
>
> No.

Again, you are ahead of me. Mine makes extremely heavy use of CPU hotplug.

> > 3. Are you seeing things like this in dmesg?
> >
> > "rcu_preempt kthread starved for 21033 jiffies"
> > "rcu_sched kthread starved for 32103 jiffies"
> > "rcu_bh kthread starved for 84031 jiffies"
> >
> > If not, you are probably facing some other bug, and should
> > proceed debugging as described in Documentation/RCU/stallwarn.txt.
>
> Below is a sample of what I see as captured with v4.5. The kernel configuration is attached.
>
> [ 135.456197] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 135.457729] 3-...: (0 ticks this GP) idle=722/0/0 softirq=5532/5532 fqs=0
> [ 135.459604] (detected by 2, t=60004 jiffies, g=2105, c=2104, q=165)
> [ 135.461318] Task dump for CPU 3:
> [ 135.461321] swapper/3 R running task 0 0 1 0x00200000
> [ 135.461325] 00000078560040e5 ffff88017846fed0 ffffffff818af2cc ffff880100000000
> [ 135.461330] 0000000600000003 ffff880178470000 ffff880072f32200 ffffffff822dcec0
> [ 135.461334] ffff88017846c000 ffff88017846c000 ffff88017846fee0 ffffffff818af517
> [ 135.461338] Call Trace:
> [ 135.461345] [<ffffffff818af2cc>] ? cpuidle_enter_state+0xfc/0x310
> [ 135.461349] [<ffffffff818af517>] ? cpuidle_enter+0x17/0x20
> [ 135.461353] [<ffffffff811515aa>] ? call_cpuidle+0x2a/0x40
> [ 135.461355] [<ffffffff8115197d>] ? cpu_startup_entry+0x28d/0x360
> [ 135.461360] [<ffffffff8108c874>] ? start_secondary+0x114/0x140
> [ 135.461365] rcu_preempt kthread starved for 60004 jiffies! g2105 c2104 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1

And yes, it looks like you are seeing the same bug that I am tracing.

The kthread is blocked on a schedule_timeout_interruptible(). Given
default configuration, this would have a three-jiffy timeout.

You set CONFIG_RCU_CPU_STALL_TIMEOUT=60, which matches the 60004 jiffies
above. Is that value due to a distro setting or something? Mainline
uses CONFIG_RCU_CPU_STALL_TIMEOUT=21.

> [ 135.463965] rcu_preempt S ffff88017844fd68 0 7 2 0x00000000
> [ 135.463969] ffff88017844fd68 ffff88017dd8cc80 ffff880177ff0000 ffff880178443b80
> [ 135.463973] ffff880178450000 ffff88017844fda0 ffff88017dd8cc80 ffff88017dd8cc80
> [ 135.463977] 0000000000000003 ffff88017844fd80 ffffffff81ab031f 0000000100031504
> [ 135.463981] Call Trace:
> [ 135.463986] [<ffffffff81ab031f>] schedule+0x3f/0xa0
> [ 135.463989] [<ffffffff81ab42d7>] schedule_timeout+0x127/0x270
> [ 135.463993] [<ffffffff81171a50>] ? detach_if_pending+0x120/0x120
> [ 135.463997] [<ffffffff8116da5d>] rcu_gp_kthread+0x6bd/0xa30
> [ 135.464000] [<ffffffff81151390>] ? wake_atomic_t_function+0x70/0x70
> [ 135.464003] [<ffffffff8116d3a0>] ? force_qs_rnp+0x1b0/0x1b0
> [ 135.464006] [<ffffffff8112f846>] kthread+0xe6/0x100
> [ 135.464009] [<ffffffff8112f760>] ? kthread_worker_fn+0x190/0x190
> [ 135.464012] [<ffffffff81ab5c0f>] ret_from_fork+0x3f/0x70
> [ 135.464015] [<ffffffff8112f760>] ? kthread_worker_fn+0x190/0x190

How long does it take to reproduce this? If it reproduces in minutes
or hours, could you please boot with the following on the kernel command
line and dump the trace buffer shortly after the stall?

ftrace trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi

If dumping manually shortly after the stall is at all non-trivial
(for example, if your reproduction time is many minute or hours),
I can supply some patches that automate this. Or you can pick
them up from -rcu:

git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git

Branch rcu/dev has these patches (and much else besides).

Thanx, Paul

PS: In case you are curious, when I enable those tracepoints, it
shows me that the timer is firing every three jiffies, as it
should, but that something happens between the sched_waking
and the IPI handler that should actually do the wakeup.
However, adding the traces significantly slows reproduction,
so I am writing a stress test specific to this bug to try to
speed things up, hopefully allowing more tracing to be added
while still retaining non-geologic reproduction times.

2016-03-22 21:06:09

by Reinette Chatre

[permalink] [raw]
Subject: RE: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

Hi Paul,

On 2016-03-22, Paul E. McKenney wrote:
> On Tue, Mar 22, 2016 at 04:35:32PM +0000, Chatre, Reinette wrote:
>> On 2016-03-21, Paul E. McKenney wrote:
>>> On Mon, Mar 21, 2016 at 09:22:30AM -0700, Jacob Pan wrote:
>>>> On Fri, 18 Mar 2016 16:56:41 -0700
>>>> "Paul E. McKenney" <[email protected]> wrote:
>>>>> On Fri, Mar 18, 2016 at 02:00:11PM -0700, Josh Triplett wrote:
>>>>>> On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:
>>>
>>> [ . . . ]
>>>
>>>>>> We're seeing a similar stall (~60 seconds) on an x86 development
>>>>>> system here. Any luck tracking down the cause of this? If not, any
>>>>>> suggestions for traces that might be helpful?
>>>>>
>>>>> The dmesg containing the stall, the kernel version, and the .config
>>>>> would be helpful! Working on a torture test specific to this bug...
>
> And thank you for the .config. Your kenrle version looks to be 4.5.0.
>
>>>> +Reinette, she has the system that can reproduce the issue. I
>>>> believe she is having some other problems with it at the moment. But
>>>> the .config should be available. Version is v4.5.
>>>
>>> A couple of additional questions:
>>>
>>> 1. Is the test running on bare metal or virtualized? If the
>>> latter, what is the host?
>>
>> Bare metal.
>
> OK, you are ahead of me. Mine is virtualized.
>
>>> 2. Does the workload involve CPU hotplug?
>>
>> No.
>
> Again, you are ahead of me. Mine makes extremely heavy use of CPU hotplug.
>
>>> 3. Are you seeing things like this in dmesg?
>>>
>>> "rcu_preempt kthread starved for 21033 jiffies"
>>> "rcu_sched kthread starved for 32103 jiffies"
>>> "rcu_bh kthread starved for 84031 jiffies"
>>>
>>> If not, you are probably facing some other bug, and should
>>> proceed debugging as described in Documentation/RCU/stallwarn.txt.
>>
>> Below is a sample of what I see as captured with v4.5. The kernel
>> configuration is attached.
>>
>> [ 135.456197] INFO: rcu_preempt detected stalls on CPUs/tasks: [
>> 135.457729] 3-...: (0 ticks this GP) idle=722/0/0 softirq=5532/5532
>> fqs=0 [ 135.459604] (detected by 2, t=60004 jiffies, g=2105, c=2104,
>> q=165) [ 135.461318] Task dump for CPU 3: [ 135.461321] swapper/3
>> R running task 0 0 1 0x00200000 [ 135.461325]
>> 00000078560040e5 ffff88017846fed0 ffffffff818af2cc ffff880100000000 [
>> 135.461330] 0000000600000003 ffff880178470000 ffff880072f32200
>> ffffffff822dcec0 [ 135.461334] ffff88017846c000 ffff88017846c000
>> ffff88017846fee0 ffffffff818af517 [ 135.461338] Call Trace: [
>> 135.461345] [<ffffffff818af2cc>] ? cpuidle_enter_state+0xfc/0x310 [
>> 135.461349] [<ffffffff818af517>] ? cpuidle_enter+0x17/0x20 [
>> 135.461353] [<ffffffff811515aa>] ? call_cpuidle+0x2a/0x40 [
>> 135.461355] [<ffffffff8115197d>] ? cpu_startup_entry+0x28d/0x360 [
>> 135.461360] [<ffffffff8108c874>] ? start_secondary+0x114/0x140 [
>> 135.461365] rcu_preempt kthread starved for 60004 jiffies! g2105 c2104
> f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
>
> And yes, it looks like you are seeing the same bug that I am tracing.
>
> The kthread is blocked on a schedule_timeout_interruptible(). Given
> default configuration, this would have a three-jiffy timeout.
>
> You set CONFIG_RCU_CPU_STALL_TIMEOUT=60, which matches the 60004 jiffies
> above. Is that value due to a distro setting or something? Mainline
> uses CONFIG_RCU_CPU_STALL_TIMEOUT=21.

Indeed ... this value originated from a Fedora configuration.

>> [ 135.463965] rcu_preempt S ffff88017844fd68 0 7 2
>> 0x00000000 [ 135.463969] ffff88017844fd68 ffff88017dd8cc80
>> ffff880177ff0000 ffff880178443b80 [ 135.463973] ffff880178450000
>> ffff88017844fda0 ffff88017dd8cc80 ffff88017dd8cc80 [ 135.463977]
>> 0000000000000003 ffff88017844fd80 ffffffff81ab031f 0000000100031504 [
>> 135.463981] Call Trace: [ 135.463986] [<ffffffff81ab031f>]
>> schedule+0x3f/0xa0 [ 135.463989] [<ffffffff81ab42d7>]
>> schedule_timeout+0x127/0x270 [ 135.463993] [<ffffffff81171a50>] ?
>> detach_if_pending+0x120/0x120 [ 135.463997] [<ffffffff8116da5d>]
>> rcu_gp_kthread+0x6bd/0xa30 [ 135.464000] [<ffffffff81151390>] ?
>> wake_atomic_t_function+0x70/0x70 [ 135.464003] [<ffffffff8116d3a0>] ?
>> force_qs_rnp+0x1b0/0x1b0 [ 135.464006] [<ffffffff8112f846>]
>> kthread+0xe6/0x100 [ 135.464009] [<ffffffff8112f760>] ?
>> kthread_worker_fn+0x190/0x190 [ 135.464012] [<ffffffff81ab5c0f>]
>> ret_from_fork+0x3f/0x70 [ 135.464015] [<ffffffff8112f760>] ?
>> kthread_worker_fn+0x190/0x190
>
> How long does it take to reproduce this? If it reproduces in minutes
> or hours, could you please boot with the following on the kernel command
> line and dump the trace buffer shortly after the stall?
>
> ftrace trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi

The trace I provided above appeared after a few minutes and not again. On previous occasions I had to wait a few hours. I tried running with the above added to the kernel command line but I have not seen the trace yet. I will leave the system overnight but then may risk not capturing the data you need so ...

> If dumping manually shortly after the stall is at all non-trivial
> (for example, if your reproduction time is many minute or hours),
> I can supply some patches that automate this. Or you can pick
> them up from -rcu:

... could you please point me to the patches you refer to? Or would you like me to try with the entire kernel from rcu/dev?

>
> git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
>
> Branch rcu/dev has these patches (and much else besides).
>
> Thanx, Paul
>
> PS: In case you are curious, when I enable those tracepoints, it
> shows me that the timer is firing every three jiffies, as it
> should, but that something happens between the sched_waking
> and the IPI handler that should actually do the wakeup.
> However, adding the traces significantly slows reproduction,
> so I am writing a stress test specific to this bug to try to
> speed things up, hopefully allowing more tracing to be added
> while still retaining non-geologic reproduction times.

Thank you very much for these details.

Reinette

2016-03-22 21:19:41

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Tue, Mar 22, 2016 at 09:04:47PM +0000, Chatre, Reinette wrote:
> Hi Paul,
>
> On 2016-03-22, Paul E. McKenney wrote:
> > On Tue, Mar 22, 2016 at 04:35:32PM +0000, Chatre, Reinette wrote:
> >> On 2016-03-21, Paul E. McKenney wrote:
> >>> On Mon, Mar 21, 2016 at 09:22:30AM -0700, Jacob Pan wrote:
> >>>> On Fri, 18 Mar 2016 16:56:41 -0700
> >>>> "Paul E. McKenney" <[email protected]> wrote:
> >>>>> On Fri, Mar 18, 2016 at 02:00:11PM -0700, Josh Triplett wrote:
> >>>>>> On Thu, Feb 25, 2016 at 04:56:38PM -0800, Paul E. McKenney wrote:
> >>>
> >>> [ . . . ]
> >>>
> >>>>>> We're seeing a similar stall (~60 seconds) on an x86 development
> >>>>>> system here. Any luck tracking down the cause of this? If not, any
> >>>>>> suggestions for traces that might be helpful?
> >>>>>
> >>>>> The dmesg containing the stall, the kernel version, and the .config
> >>>>> would be helpful! Working on a torture test specific to this bug...
> >
> > And thank you for the .config. Your kenrle version looks to be 4.5.0.
> >
> >>>> +Reinette, she has the system that can reproduce the issue. I
> >>>> believe she is having some other problems with it at the moment. But
> >>>> the .config should be available. Version is v4.5.
> >>>
> >>> A couple of additional questions:
> >>>
> >>> 1. Is the test running on bare metal or virtualized? If the
> >>> latter, what is the host?
> >>
> >> Bare metal.
> >
> > OK, you are ahead of me. Mine is virtualized.
> >
> >>> 2. Does the workload involve CPU hotplug?
> >>
> >> No.
> >
> > Again, you are ahead of me. Mine makes extremely heavy use of CPU hotplug.
> >
> >>> 3. Are you seeing things like this in dmesg?
> >>>
> >>> "rcu_preempt kthread starved for 21033 jiffies"
> >>> "rcu_sched kthread starved for 32103 jiffies"
> >>> "rcu_bh kthread starved for 84031 jiffies"
> >>>
> >>> If not, you are probably facing some other bug, and should
> >>> proceed debugging as described in Documentation/RCU/stallwarn.txt.
> >>
> >> Below is a sample of what I see as captured with v4.5. The kernel
> >> configuration is attached.
> >>
> >> [ 135.456197] INFO: rcu_preempt detected stalls on CPUs/tasks: [
> >> 135.457729] 3-...: (0 ticks this GP) idle=722/0/0 softirq=5532/5532
> >> fqs=0 [ 135.459604] (detected by 2, t=60004 jiffies, g=2105, c=2104,
> >> q=165) [ 135.461318] Task dump for CPU 3: [ 135.461321] swapper/3
> >> R running task 0 0 1 0x00200000 [ 135.461325]
> >> 00000078560040e5 ffff88017846fed0 ffffffff818af2cc ffff880100000000 [
> >> 135.461330] 0000000600000003 ffff880178470000 ffff880072f32200
> >> ffffffff822dcec0 [ 135.461334] ffff88017846c000 ffff88017846c000
> >> ffff88017846fee0 ffffffff818af517 [ 135.461338] Call Trace: [
> >> 135.461345] [<ffffffff818af2cc>] ? cpuidle_enter_state+0xfc/0x310 [
> >> 135.461349] [<ffffffff818af517>] ? cpuidle_enter+0x17/0x20 [
> >> 135.461353] [<ffffffff811515aa>] ? call_cpuidle+0x2a/0x40 [
> >> 135.461355] [<ffffffff8115197d>] ? cpu_startup_entry+0x28d/0x360 [
> >> 135.461360] [<ffffffff8108c874>] ? start_secondary+0x114/0x140 [
> >> 135.461365] rcu_preempt kthread starved for 60004 jiffies! g2105 c2104
> > f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> >
> > And yes, it looks like you are seeing the same bug that I am tracing.
> >
> > The kthread is blocked on a schedule_timeout_interruptible(). Given
> > default configuration, this would have a three-jiffy timeout.
> >
> > You set CONFIG_RCU_CPU_STALL_TIMEOUT=60, which matches the 60004 jiffies
> > above. Is that value due to a distro setting or something? Mainline
> > uses CONFIG_RCU_CPU_STALL_TIMEOUT=21.
>
> Indeed ... this value originated from a Fedora configuration.

OK. Setting it shorter might (or might not) make it reproduce more
quickly. This can be set at boot time via rcupdate.rcu_cpu_stall_timeout.
Or at compile time via CONFIG_RCU_CPU_STALL_TIMEOUT.

> >> [ 135.463965] rcu_preempt S ffff88017844fd68 0 7 2
> >> 0x00000000 [ 135.463969] ffff88017844fd68 ffff88017dd8cc80
> >> ffff880177ff0000 ffff880178443b80 [ 135.463973] ffff880178450000
> >> ffff88017844fda0 ffff88017dd8cc80 ffff88017dd8cc80 [ 135.463977]
> >> 0000000000000003 ffff88017844fd80 ffffffff81ab031f 0000000100031504 [
> >> 135.463981] Call Trace: [ 135.463986] [<ffffffff81ab031f>]
> >> schedule+0x3f/0xa0 [ 135.463989] [<ffffffff81ab42d7>]
> >> schedule_timeout+0x127/0x270 [ 135.463993] [<ffffffff81171a50>] ?
> >> detach_if_pending+0x120/0x120 [ 135.463997] [<ffffffff8116da5d>]
> >> rcu_gp_kthread+0x6bd/0xa30 [ 135.464000] [<ffffffff81151390>] ?
> >> wake_atomic_t_function+0x70/0x70 [ 135.464003] [<ffffffff8116d3a0>] ?
> >> force_qs_rnp+0x1b0/0x1b0 [ 135.464006] [<ffffffff8112f846>]
> >> kthread+0xe6/0x100 [ 135.464009] [<ffffffff8112f760>] ?
> >> kthread_worker_fn+0x190/0x190 [ 135.464012] [<ffffffff81ab5c0f>]
> >> ret_from_fork+0x3f/0x70 [ 135.464015] [<ffffffff8112f760>] ?
> >> kthread_worker_fn+0x190/0x190
> >
> > How long does it take to reproduce this? If it reproduces in minutes
> > or hours, could you please boot with the following on the kernel command
> > line and dump the trace buffer shortly after the stall?
> >
> > ftrace trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
>
> The trace I provided above appeared after a few minutes and not again. On previous occasions I had to wait a few hours. I tried running with the above added to the kernel command line but I have not seen the trace yet. I will leave the system overnight but then may risk not capturing the data you need so ...

Fair enough... Sounds like you might have the same geologic-time
problem that I do when adding tracing. :-/

> > If dumping manually shortly after the stall is at all non-trivial
> > (for example, if your reproduction time is many minute or hours),
> > I can supply some patches that automate this. Or you can pick
> > them up from -rcu:
>
> ... could you please point me to the patches you refer to? Or would you like me to try with the entire kernel from rcu/dev?

2dc92e2a86b9 (rcu: Awaken grace-period kthread if too long since FQS)
c3fd2095d015 (rcu: Dump ftrace buffer when kicking grace-period kthread)

There might be other dependencies, but these are the two that you need.

Thanx, Paul

> > git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git
> >
> > Branch rcu/dev has these patches (and much else besides).
> >
> > Thanx, Paul
> >
> > PS: In case you are curious, when I enable those tracepoints, it
> > shows me that the timer is firing every three jiffies, as it
> > should, but that something happens between the sched_waking
> > and the IPI handler that should actually do the wakeup.
> > However, adding the traces significantly slows reproduction,
> > so I am writing a stress test specific to this bug to try to
> > speed things up, hopefully allowing more tracing to be added
> > while still retaining non-geologic reproduction times.
>
> Thank you very much for these details.
>
> Reinette
>

2016-03-23 17:15:27

by Reinette Chatre

[permalink] [raw]
Subject: RE: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

Hi Paul,

On 2016-03-22, Paul E. McKenney wrote:
> On Tue, Mar 22, 2016 at 09:04:47PM +0000, Chatre, Reinette wrote:
>> On 2016-03-22, Paul E. McKenney wrote:
>>> You set CONFIG_RCU_CPU_STALL_TIMEOUT=60, which matches the 60004
>>> jiffies above. Is that value due to a distro setting or something?
>>> Mainline uses CONFIG_RCU_CPU_STALL_TIMEOUT=21.
>>
>> Indeed ... this value originated from a Fedora configuration.
>
> OK. Setting it shorter might (or might not) make it reproduce more
> quickly. This can be set at boot time via rcupdate.rcu_cpu_stall_timeout.
> Or at compile time via CONFIG_RCU_CPU_STALL_TIMEOUT.

I kept the original configuration and seem to be able to reproduce with that.


>>> If dumping manually shortly after the stall is at all non-trivial
>>> (for example, if your reproduction time is many minute or hours),
>>> I can supply some patches that automate this. Or you can pick
>>> them up from -rcu:
>>
>> ... could you please point me to the patches you refer to? Or would you like
> me to try with the entire kernel from rcu/dev?
>
> 2dc92e2a86b9 (rcu: Awaken grace-period kthread if too long since FQS)
> c3fd2095d015 (rcu: Dump ftrace buffer when kicking grace-period kthread)
>
> There might be other dependencies, but these are the two that you need.

I did not look closely at the patches when I applied them and because of that missed that they need a kernel parameter to be activated. After leaving the system idle overnight with these patches the stalls occurred but without the parameter I did not capture the data you need. I will try again tonight. Below are the traces from last night just in case they have value to you.

[10154.635318] INFO: rcu_preempt detected stalls on CPUs/tasks:
[10154.639218] 1-...: (0 ticks this GP) idle=c4e/0/0 softirq=99936/99936 fqs=0
[10154.643497] (detected by 0, t=60005 jiffies, g=24190, c=24189, q=79)
[10154.647596] Task dump for CPU 1:
[10154.650818] swapper/1 R running task 0 0 1 0x00200000
[10154.655052] 00002656bf74de5e ffff8801785cfed0 ffffffff818af34c ffff880100000000
[10154.659349] 0000000600000003 ffff8801785d0000 ffff880072f0bc00 ffffffff822dcf80
[10154.663636] ffff8801785cc000 ffff8801785cc000 ffff8801785cfee0 ffffffff818af597
[10154.667916] Call Trace:
[10154.670845] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[10154.674802] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[10154.678564] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[10154.682295] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[10154.686187] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[10154.690040] rcu_preempt kthread starved for 60005 jiffies! g24190 c24189 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[10154.694944] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[10154.699062] ffff8801785b7d68 ffff88017dc8cc80 ffff8801785c3b80 ffff8801785abb80
[10154.703275] ffff8801785b8000 ffff8801785b7da0 ffff88017dc8cc80 ffff88017dc8cc80
[10154.707481] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 00000001027e21aa
[10154.711692] Call Trace:
[10154.714548] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[10154.718075] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[10154.721832] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[10154.725659] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[10154.729379] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[10154.733235] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[10154.736854] [<ffffffff8112f856>] kthread+0xe6/0x100
[10154.740267] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[10154.743980] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[10154.747511] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11348.912706] INFO: rcu_preempt detected stalls on CPUs/tasks:
[11348.916346] 2-...: (0 ticks this GP) idle=586/0/0 softirq=133504/133504 fqs=0
[11348.920407] (detected by 3, t=60002 jiffies, g=26799, c=26798, q=72)
[11348.924244] Task dump for CPU 2:
[11348.927205] swapper/2 R running task 0 0 1 0x00200000
[11348.931178] 00002adc83427a76 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
[11348.935217] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
[11348.939237] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
[11348.943252] Call Trace:
[11348.945921] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[11348.949615] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[11348.953115] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[11348.956584] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[11348.960215] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[11348.963808] rcu_preempt kthread starved for 60002 jiffies! g26799 c26798 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[11348.968452] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[11348.972309] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
[11348.976266] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
[11348.980207] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102c9d45e
[11348.984142] Call Trace:
[11348.986714] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[11348.989974] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[11348.993453] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[11348.997000] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[11349.000431] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[11349.004040] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[11349.007449] [<ffffffff8112f856>] kthread+0xe6/0x100
[11349.010676] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11349.014216] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[11349.017568] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11790.539207] INFO: rcu_preempt detected stalls on CPUs/tasks:
[11790.542652] 2-...: (0 ticks this GP) idle=944/0/0 softirq=133668/133668 fqs=0
[11790.546505] (detected by 3, t=60003 jiffies, g=27589, c=27588, q=72)
[11790.550124] Task dump for CPU 2:
[11790.552871] swapper/2 R running task 0 0 1 0x00200000
[11790.556678] 00002c8422fed65e ffff8801785d3ed0 ffffffff818af34c ffff880100000000
[11790.560580] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
[11790.564485] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
[11790.568389] Call Trace:
[11790.570942] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[11790.574525] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[11790.577934] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[11790.581311] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[11790.584853] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[11790.588350] rcu_preempt kthread starved for 60003 jiffies! g27589 c27588 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[11790.592945] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[11790.596808] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
[11790.600751] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
[11790.604688] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102e5d253
[11790.608635] Call Trace:
[11790.611220] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[11790.614480] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[11790.617971] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[11790.621530] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[11790.624972] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[11790.628558] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[11790.631904] [<ffffffff8112f856>] kthread+0xe6/0x100
[11790.635043] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11790.638485] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[11790.641745] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11820.319166] INFO: rcu_preempt detected stalls on CPUs/tasks:
[11820.322523] 2-...: (0 ticks this GP) idle=9b4/0/0 softirq=133674/133674 fqs=0
[11820.326301] (detected by 3, t=60002 jiffies, g=27620, c=27619, q=64)
[11820.329856] Task dump for CPU 2:
[11820.332536] swapper/2 R running task 0 0 1 0x00200000
[11820.336228] 00002ca4dc6b2bb1 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
[11820.339990] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
[11820.343749] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
[11820.347483] Call Trace:
[11820.349852] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[11820.353250] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[11820.356463] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[11820.359637] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[11820.362973] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[11820.366264] rcu_preempt kthread starved for 60002 jiffies! g27620 c27619 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[11820.370643] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[11820.374276] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
[11820.378026] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
[11820.381775] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102e7b58c
[11820.385537] Call Trace:
[11820.387940] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[11820.391005] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[11820.394286] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[11820.397626] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[11820.400853] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[11820.404269] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[11820.407478] [<ffffffff8112f856>] kthread+0xe6/0x100
[11820.410493] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11820.413824] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[11820.416966] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11903.292474] INFO: rcu_preempt detected stalls on CPUs/tasks:
[11903.295736] 2-...: (0 ticks this GP) idle=bd2/0/0 softirq=133700/133700 fqs=0
[11903.299427] (detected by 3, t=60003 jiffies, g=27759, c=27758, q=277)
[11903.302921] Task dump for CPU 2:
[11903.305513] swapper/2 R running task 0 0 1 0x00200000
[11903.309164] 00002cf65a063204 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
[11903.312931] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
[11903.316685] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
[11903.320426] Call Trace:
[11903.322802] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[11903.326199] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[11903.329416] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[11903.332591] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[11903.335931] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[11903.339226] rcu_preempt kthread starved for 60003 jiffies! g27759 c27758 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[11903.343607] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[11903.347246] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
[11903.350999] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
[11903.354750] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102ecf7e4
[11903.358508] Call Trace:
[11903.360909] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[11903.363979] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[11903.367259] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[11903.370601] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[11903.373829] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[11903.377243] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[11903.380455] [<ffffffff8112f856>] kthread+0xe6/0x100
[11903.383473] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[11903.386804] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[11903.389942] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[12101.322638] INFO: rcu_preempt detected stalls on CPUs/tasks:
[12101.325902] 2-...: (19 GPs behind) idle=880/0/0 softirq=133768/133768 fqs=1
[12101.329542] (detected by 1, t=60004 jiffies, g=28170, c=28169, q=41)
[12101.333009] Task dump for CPU 2:
[12101.335599] swapper/2 R running task 0 0 1 0x00200000
[12101.339248] 00002db4171b61e1 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
[12101.343008] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
[12101.346763] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
[12101.350501] Call Trace:
[12101.352868] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[12101.356262] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[12101.359475] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[12101.362645] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[12101.365980] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[12101.369270] rcu_preempt kthread starved for 60000 jiffies! g28170 c28169 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[12101.373646] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[12101.377281] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
[12101.381030] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
[12101.384778] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102f98533
[12101.388532] Call Trace:
[12101.390927] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[12101.393991] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[12101.397266] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[12101.400602] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[12101.403825] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[12101.407240] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[12101.410450] [<ffffffff8112f856>] kthread+0xe6/0x100
[12101.413465] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[12101.416793] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[12101.419930] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[12269.411058] INFO: rcu_preempt detected stalls on CPUs/tasks:
[12269.414316] 2-...: (27 GPs behind) idle=daa/0/0 softirq=133902/133902 fqs=1
[12269.417947] (detected by 0, t=60003 jiffies, g=28504, c=28503, q=347)
[12269.421426] Task dump for CPU 2:
[12269.424012] swapper/2 R running task 0 0 1 0x00200000
[12269.427656] 00002e58b5f8d033 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
[12269.431405] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
[12269.435153] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
[12269.438886] Call Trace:
[12269.441252] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[12269.444638] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[12269.447850] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[12269.451014] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[12269.454348] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[12269.457634] rcu_preempt kthread starved for 59872 jiffies! g28504 c28503 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[12269.462008] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[12269.465636] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
[12269.469380] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
[12269.473121] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000103042d26
[12269.476868] Call Trace:
[12269.479262] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[12269.482321] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[12269.485592] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[12269.488926] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[12269.492144] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[12269.495554] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[12269.498756] [<ffffffff8112f856>] kthread+0xe6/0x100
[12269.501764] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[12269.505090] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[12269.508224] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[12426.587923] INFO: rcu_preempt detected stalls on CPUs/tasks:
[12426.591181] 2-...: (17 GPs behind) idle=15c/0/0 softirq=134033/134034 fqs=1
[12426.594815] (detected by 0, t=60002 jiffies, g=28804, c=28803, q=396)
[12426.598296] Task dump for CPU 2:
[12426.600881] swapper/2 R running task 0 0 1 0x00200000
[12426.604528] 00002eed4414d5d4 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
[12426.608284] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
[12426.612030] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
[12426.615762] Call Trace:
[12426.618131] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[12426.621522] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[12426.624733] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[12426.627903] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[12426.631238] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[12426.634527] rcu_preempt kthread starved for 59998 jiffies! g28804 c28803 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[12426.638900] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[12426.642535] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
[12426.646285] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
[12426.650031] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 00000001030e230e
[12426.653787] Call Trace:
[12426.656186] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[12426.659251] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[12426.662528] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[12426.665868] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[12426.669091] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[12426.672502] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[12426.675710] [<ffffffff8112f856>] kthread+0xe6/0x100
[12426.678724] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[12426.682052] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[12426.685188] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190


2016-03-23 18:21:12

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Wed, Mar 23, 2016 at 05:15:11PM +0000, Chatre, Reinette wrote:
> Hi Paul,
>
> On 2016-03-22, Paul E. McKenney wrote:
> > On Tue, Mar 22, 2016 at 09:04:47PM +0000, Chatre, Reinette wrote:
> >> On 2016-03-22, Paul E. McKenney wrote:
> >>> You set CONFIG_RCU_CPU_STALL_TIMEOUT=60, which matches the 60004
> >>> jiffies above. Is that value due to a distro setting or something?
> >>> Mainline uses CONFIG_RCU_CPU_STALL_TIMEOUT=21.
> >>
> >> Indeed ... this value originated from a Fedora configuration.
> >
> > OK. Setting it shorter might (or might not) make it reproduce more
> > quickly. This can be set at boot time via rcupdate.rcu_cpu_stall_timeout.
> > Or at compile time via CONFIG_RCU_CPU_STALL_TIMEOUT.
>
> I kept the original configuration and seem to be able to reproduce with that.
>
>
> >>> If dumping manually shortly after the stall is at all non-trivial
> >>> (for example, if your reproduction time is many minute or hours),
> >>> I can supply some patches that automate this. Or you can pick
> >>> them up from -rcu:
> >>
> >> ... could you please point me to the patches you refer to? Or would you like
> > me to try with the entire kernel from rcu/dev?
> >
> > 2dc92e2a86b9 (rcu: Awaken grace-period kthread if too long since FQS)
> > c3fd2095d015 (rcu: Dump ftrace buffer when kicking grace-period kthread)
> >
> > There might be other dependencies, but these are the two that you need.
>
> I did not look closely at the patches when I applied them and because
> of that missed that they need a kernel parameter to be activated. After
> leaving the system idle overnight with these patches the stalls occurred
> but without the parameter I did not capture the data you need. I will
> try again tonight. Below are the traces from last night just in case
> they have value to you.

I know that feeling!

Please boot with the following parameters:

rcu_tree.rcu_kick_kthreads ftrace trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi

Or was this run with tracing? If so, less than three hours isn't too bad.

> [10154.635318] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [10154.639218] 1-...: (0 ticks this GP) idle=c4e/0/0 softirq=99936/99936 fqs=0
> [10154.643497] (detected by 0, t=60005 jiffies, g=24190, c=24189, q=79)
> [10154.647596] Task dump for CPU 1:
> [10154.650818] swapper/1 R running task 0 0 1 0x00200000
> [10154.655052] 00002656bf74de5e ffff8801785cfed0 ffffffff818af34c ffff880100000000
> [10154.659349] 0000000600000003 ffff8801785d0000 ffff880072f0bc00 ffffffff822dcf80
> [10154.663636] ffff8801785cc000 ffff8801785cc000 ffff8801785cfee0 ffffffff818af597
> [10154.667916] Call Trace:
> [10154.670845] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [10154.674802] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [10154.678564] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [10154.682295] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [10154.686187] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [10154.690040] rcu_preempt kthread starved for 60005 jiffies! g24190 c24189 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1

Still the same type of failure, which is reassuring.

Thanx, Paul

> [10154.694944] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [10154.699062] ffff8801785b7d68 ffff88017dc8cc80 ffff8801785c3b80 ffff8801785abb80
> [10154.703275] ffff8801785b8000 ffff8801785b7da0 ffff88017dc8cc80 ffff88017dc8cc80
> [10154.707481] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 00000001027e21aa
> [10154.711692] Call Trace:
> [10154.714548] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [10154.718075] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [10154.721832] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [10154.725659] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [10154.729379] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [10154.733235] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [10154.736854] [<ffffffff8112f856>] kthread+0xe6/0x100
> [10154.740267] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [10154.743980] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [10154.747511] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11348.912706] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [11348.916346] 2-...: (0 ticks this GP) idle=586/0/0 softirq=133504/133504 fqs=0
> [11348.920407] (detected by 3, t=60002 jiffies, g=26799, c=26798, q=72)
> [11348.924244] Task dump for CPU 2:
> [11348.927205] swapper/2 R running task 0 0 1 0x00200000
> [11348.931178] 00002adc83427a76 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
> [11348.935217] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
> [11348.939237] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
> [11348.943252] Call Trace:
> [11348.945921] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [11348.949615] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [11348.953115] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [11348.956584] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [11348.960215] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [11348.963808] rcu_preempt kthread starved for 60002 jiffies! g26799 c26798 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [11348.968452] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [11348.972309] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
> [11348.976266] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
> [11348.980207] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102c9d45e
> [11348.984142] Call Trace:
> [11348.986714] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [11348.989974] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [11348.993453] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [11348.997000] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [11349.000431] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [11349.004040] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [11349.007449] [<ffffffff8112f856>] kthread+0xe6/0x100
> [11349.010676] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11349.014216] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [11349.017568] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11790.539207] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [11790.542652] 2-...: (0 ticks this GP) idle=944/0/0 softirq=133668/133668 fqs=0
> [11790.546505] (detected by 3, t=60003 jiffies, g=27589, c=27588, q=72)
> [11790.550124] Task dump for CPU 2:
> [11790.552871] swapper/2 R running task 0 0 1 0x00200000
> [11790.556678] 00002c8422fed65e ffff8801785d3ed0 ffffffff818af34c ffff880100000000
> [11790.560580] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
> [11790.564485] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
> [11790.568389] Call Trace:
> [11790.570942] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [11790.574525] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [11790.577934] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [11790.581311] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [11790.584853] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [11790.588350] rcu_preempt kthread starved for 60003 jiffies! g27589 c27588 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [11790.592945] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [11790.596808] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
> [11790.600751] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
> [11790.604688] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102e5d253
> [11790.608635] Call Trace:
> [11790.611220] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [11790.614480] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [11790.617971] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [11790.621530] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [11790.624972] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [11790.628558] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [11790.631904] [<ffffffff8112f856>] kthread+0xe6/0x100
> [11790.635043] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11790.638485] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [11790.641745] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11820.319166] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [11820.322523] 2-...: (0 ticks this GP) idle=9b4/0/0 softirq=133674/133674 fqs=0
> [11820.326301] (detected by 3, t=60002 jiffies, g=27620, c=27619, q=64)
> [11820.329856] Task dump for CPU 2:
> [11820.332536] swapper/2 R running task 0 0 1 0x00200000
> [11820.336228] 00002ca4dc6b2bb1 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
> [11820.339990] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
> [11820.343749] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
> [11820.347483] Call Trace:
> [11820.349852] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [11820.353250] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [11820.356463] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [11820.359637] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [11820.362973] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [11820.366264] rcu_preempt kthread starved for 60002 jiffies! g27620 c27619 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [11820.370643] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [11820.374276] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
> [11820.378026] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
> [11820.381775] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102e7b58c
> [11820.385537] Call Trace:
> [11820.387940] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [11820.391005] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [11820.394286] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [11820.397626] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [11820.400853] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [11820.404269] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [11820.407478] [<ffffffff8112f856>] kthread+0xe6/0x100
> [11820.410493] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11820.413824] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [11820.416966] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11903.292474] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [11903.295736] 2-...: (0 ticks this GP) idle=bd2/0/0 softirq=133700/133700 fqs=0
> [11903.299427] (detected by 3, t=60003 jiffies, g=27759, c=27758, q=277)
> [11903.302921] Task dump for CPU 2:
> [11903.305513] swapper/2 R running task 0 0 1 0x00200000
> [11903.309164] 00002cf65a063204 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
> [11903.312931] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
> [11903.316685] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
> [11903.320426] Call Trace:
> [11903.322802] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [11903.326199] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [11903.329416] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [11903.332591] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [11903.335931] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [11903.339226] rcu_preempt kthread starved for 60003 jiffies! g27759 c27758 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [11903.343607] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [11903.347246] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
> [11903.350999] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
> [11903.354750] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102ecf7e4
> [11903.358508] Call Trace:
> [11903.360909] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [11903.363979] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [11903.367259] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [11903.370601] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [11903.373829] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [11903.377243] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [11903.380455] [<ffffffff8112f856>] kthread+0xe6/0x100
> [11903.383473] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [11903.386804] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [11903.389942] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [12101.322638] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [12101.325902] 2-...: (19 GPs behind) idle=880/0/0 softirq=133768/133768 fqs=1
> [12101.329542] (detected by 1, t=60004 jiffies, g=28170, c=28169, q=41)
> [12101.333009] Task dump for CPU 2:
> [12101.335599] swapper/2 R running task 0 0 1 0x00200000
> [12101.339248] 00002db4171b61e1 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
> [12101.343008] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
> [12101.346763] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
> [12101.350501] Call Trace:
> [12101.352868] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [12101.356262] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [12101.359475] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [12101.362645] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [12101.365980] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [12101.369270] rcu_preempt kthread starved for 60000 jiffies! g28170 c28169 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [12101.373646] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [12101.377281] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
> [12101.381030] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
> [12101.384778] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000102f98533
> [12101.388532] Call Trace:
> [12101.390927] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [12101.393991] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [12101.397266] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [12101.400602] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [12101.403825] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [12101.407240] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [12101.410450] [<ffffffff8112f856>] kthread+0xe6/0x100
> [12101.413465] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [12101.416793] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [12101.419930] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [12269.411058] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [12269.414316] 2-...: (27 GPs behind) idle=daa/0/0 softirq=133902/133902 fqs=1
> [12269.417947] (detected by 0, t=60003 jiffies, g=28504, c=28503, q=347)
> [12269.421426] Task dump for CPU 2:
> [12269.424012] swapper/2 R running task 0 0 1 0x00200000
> [12269.427656] 00002e58b5f8d033 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
> [12269.431405] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
> [12269.435153] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
> [12269.438886] Call Trace:
> [12269.441252] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [12269.444638] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [12269.447850] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [12269.451014] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [12269.454348] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [12269.457634] rcu_preempt kthread starved for 59872 jiffies! g28504 c28503 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [12269.462008] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [12269.465636] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
> [12269.469380] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
> [12269.473121] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000103042d26
> [12269.476868] Call Trace:
> [12269.479262] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [12269.482321] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [12269.485592] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [12269.488926] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [12269.492144] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [12269.495554] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [12269.498756] [<ffffffff8112f856>] kthread+0xe6/0x100
> [12269.501764] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [12269.505090] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [12269.508224] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [12426.587923] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [12426.591181] 2-...: (17 GPs behind) idle=15c/0/0 softirq=134033/134034 fqs=1
> [12426.594815] (detected by 0, t=60002 jiffies, g=28804, c=28803, q=396)
> [12426.598296] Task dump for CPU 2:
> [12426.600881] swapper/2 R running task 0 0 1 0x00200000
> [12426.604528] 00002eed4414d5d4 ffff8801785d3ed0 ffffffff818af34c ffff880100000000
> [12426.608284] 0000000600000003 ffff8801785d4000 ffff880177d01e00 ffffffff822dcf80
> [12426.612030] ffff8801785d0000 ffff8801785d0000 ffff8801785d3ee0 ffffffff818af597
> [12426.615762] Call Trace:
> [12426.618131] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [12426.621522] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [12426.624733] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [12426.627903] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [12426.631238] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [12426.634527] rcu_preempt kthread starved for 59998 jiffies! g28804 c28803 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [12426.638900] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [12426.642535] ffff8801785b7d68 ffff88017dd0cc80 ffff8801785c5940 ffff8801785abb80
> [12426.646285] ffff8801785b8000 ffff8801785b7da0 ffff88017dd0cc80 ffff88017dd0cc80
> [12426.650031] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 00000001030e230e
> [12426.653787] Call Trace:
> [12426.656186] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [12426.659251] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [12426.662528] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [12426.665868] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [12426.669091] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [12426.672502] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [12426.675710] [<ffffffff8112f856>] kthread+0xe6/0x100
> [12426.678724] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [12426.682052] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [12426.685188] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
>
>

2016-03-23 18:25:54

by Reinette Chatre

[permalink] [raw]
Subject: RE: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

Hi Paul,

On 2016-03-23, Paul E. McKenney wrote:
> Please boot with the following parameters:
>
> rcu_tree.rcu_kick_kthreads ftrace
> trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
>
> Or was this run with tracing? If so, less than three hours isn't too bad.

This was with tracing enabled, only missing the crucial rcu_tree.rcu_kick_kthreads

Reinette

2016-03-23 19:50:21

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Wed, Mar 23, 2016 at 06:25:50PM +0000, Chatre, Reinette wrote:
> Hi Paul,
>
> On 2016-03-23, Paul E. McKenney wrote:
> > Please boot with the following parameters:
> >
> > rcu_tree.rcu_kick_kthreads ftrace
> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
> >
> > Or was this run with tracing? If so, less than three hours isn't too bad.
>
> This was with tracing enabled, only missing the crucial
> rcu_tree.rcu_kick_kthreads

Good, then the condition did trigger with tracing enabled! ;-)

Thanx, Paul

2016-03-25 21:24:20

by Reinette Chatre

[permalink] [raw]
Subject: RE: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

Hi Paul,

On 2016-03-23, Paul E. McKenney wrote:
> Please boot with the following parameters:
>
> rcu_tree.rcu_kick_kthreads ftrace
> trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi

With these parameters I expected more details to show up in the kernel logs but cannot find any. Even so, today I left the machine running again and when this happened I think I was able to capture the trace data for the event. Please find attached the trace information for the kernel message below. Since the complete trace file is very big I trimmed it to show the time around this event - hopefully this will contain the information you need. I would also like to provide some additional information. The system on which I see these events had a time that was _very_ wrong. I noticed that this issue occurs when system-timesynd was one of the tasks calling the functions of interest to your tracing and am wondering if a very out of sync time in process of being corrected could be the cause of this issue? As an experiment I ensured the system time was accurate before leaving the system idle overnight and I did not see the issue the next morning.

[ 957.396537] INFO: rcu_preempt detected stalls on CPUs/tasks:
[ 957.399933] 1-...: (0 ticks this GP) idle=4d6/0/0 softirq=6311/6311 fqs=0
[ 957.403661] (detected by 0, t=60002 jiffies, g=3583, c=3582, q=47)
[ 957.407227] Task dump for CPU 1:
[ 957.409964] swapper/1 R running task 0 0 1 0x00200000
[ 957.413770] 0000039daa9a7eb9 ffff8801785cfed0 ffffffff818af34c ffff880100000000
[ 957.417696] 0000000600000003 ffff8801785d0000 ffff880072f9ea00 ffffffff822dcf80
[ 957.421631] ffff8801785cc000 ffff8801785cc000 ffff8801785cfee0 ffffffff818af597
[ 957.425562] Call Trace:
[ 957.428124] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
[ 957.431713] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
[ 957.435122] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
[ 957.438467] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
[ 957.441949] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
[ 957.445378] rcu_preempt kthread starved for 60002 jiffies! g3583 c3582 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
[ 957.449834] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
[ 957.453579] ffff8801785b7d68 ffff88017dc8cc80 ffff88016fe6bb80 ffff8801785abb80
[ 957.457428] ffff8801785b8000 ffff8801785b7da0 ffff88017dc8cc80 ffff88017dc8cc80
[ 957.461249] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000100373021
[ 957.465055] Call Trace:
[ 957.467493] [<ffffffff81ab03df>] schedule+0x3f/0xa0
[ 957.470613] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
[ 957.473976] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
[ 957.477387] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
[ 957.480659] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
[ 957.484123] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
[ 957.487392] [<ffffffff8112f856>] kthread+0xe6/0x100
[ 957.490470] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
[ 957.493859] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
[ 957.497044] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190

Reinette


Attachments:
trace.trim.gz (54.66 kB)
trace.trim.gz

2016-03-25 21:46:20

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
> Hi Paul,
>
> On 2016-03-23, Paul E. McKenney wrote:
> > Please boot with the following parameters:
> >
> > rcu_tree.rcu_kick_kthreads ftrace
> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
>
> With these parameters I expected more details to show up in the kernel logs but cannot find any. Even so, today I left the machine running again and when this happened I think I was able to capture the trace data for the event. Please find attached the trace information for the kernel message below. Since the complete trace file is very big I trimmed it to show the time around this event - hopefully this will contain the information you need. I would also like to provide some additional information. The system on which I see these events had a time that was _very_ wrong. I noticed that this issue occurs when system-timesynd was one of the tasks calling the functions of interest to your tracing and am wondering if a very out of sync time in process of being corrected could be the cause of this issue? As an experiment I ensured the system time was accurate before leaving the system idle overnight and I did not see the issue the next morning.

Ah! Yes, a sudden jump in time or a disagreement about the time among
different components of the system can definitely cause these symptoms.
We have sometimes seen these problems occur when a pair of CPUs have
wildly different ideas about what time it is, for example. Please let
me know how it goes.

Also, in your trace, there are no sched_waking events for the rcu_preempt
process that are not immediately followed by sched_wakeup, so your trace
isn't showing the problem that I am seeing.

Still beating up on my stress test, which is not yet proving to be all
that stressful. :-/

Thanx, Paul

> [ 957.396537] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 957.399933] 1-...: (0 ticks this GP) idle=4d6/0/0 softirq=6311/6311 fqs=0
> [ 957.403661] (detected by 0, t=60002 jiffies, g=3583, c=3582, q=47)
> [ 957.407227] Task dump for CPU 1:
> [ 957.409964] swapper/1 R running task 0 0 1 0x00200000
> [ 957.413770] 0000039daa9a7eb9 ffff8801785cfed0 ffffffff818af34c ffff880100000000
> [ 957.417696] 0000000600000003 ffff8801785d0000 ffff880072f9ea00 ffffffff822dcf80
> [ 957.421631] ffff8801785cc000 ffff8801785cc000 ffff8801785cfee0 ffffffff818af597
> [ 957.425562] Call Trace:
> [ 957.428124] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> [ 957.431713] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> [ 957.435122] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> [ 957.438467] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> [ 957.441949] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> [ 957.445378] rcu_preempt kthread starved for 60002 jiffies! g3583 c3582 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1
> [ 957.449834] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> [ 957.453579] ffff8801785b7d68 ffff88017dc8cc80 ffff88016fe6bb80 ffff8801785abb80
> [ 957.457428] ffff8801785b8000 ffff8801785b7da0 ffff88017dc8cc80 ffff88017dc8cc80
> [ 957.461249] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df 0000000100373021
> [ 957.465055] Call Trace:
> [ 957.467493] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> [ 957.470613] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> [ 957.473976] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> [ 957.477387] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> [ 957.480659] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> [ 957.484123] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> [ 957.487392] [<ffffffff8112f856>] kthread+0xe6/0x100
> [ 957.490470] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> [ 957.493859] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> [ 957.497044] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
>
> Reinette


2016-03-26 12:29:41

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 25, 2016, at 5:46 PM, Paul E. McKenney [email protected] wrote:

> On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
>> Hi Paul,
>>
>> On 2016-03-23, Paul E. McKenney wrote:
>> > Please boot with the following parameters:
>> >
>> > rcu_tree.rcu_kick_kthreads ftrace
>> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
>>
>> With these parameters I expected more details to show up in the kernel logs but
>> cannot find any. Even so, today I left the machine running again and when this
>> happened I think I was able to capture the trace data for the event. Please
>> find attached the trace information for the kernel message below. Since the
>> complete trace file is very big I trimmed it to show the time around this event
>> - hopefully this will contain the information you need. I would also like to
>> provide some additional information. The system on which I see these events had
>> a time that was _very_ wrong. I noticed that this issue occurs when
>> system-timesynd was one of the tasks calling the functions of interest to your
>> tracing and am wondering if a very out of sync time in process of being
>> corrected could be the cause of this issue? As an experiment I ensured the
>> system time was accurate before leaving the system idle overnight and I did not
>> see the issue the next morning.
>
> Ah! Yes, a sudden jump in time or a disagreement about the time among
> different components of the system can definitely cause these symptoms.
> We have sometimes seen these problems occur when a pair of CPUs have
> wildly different ideas about what time it is, for example. Please let
> me know how it goes.
>
> Also, in your trace, there are no sched_waking events for the rcu_preempt
> process that are not immediately followed by sched_wakeup, so your trace
> isn't showing the problem that I am seeing.

This is interesting.

Perhaps we could try with those commits reverted ?

commit e3baac47f0e82c4be632f4f97215bb93bf16b342
Author: Peter Zijlstra <[email protected]>
Date: Wed Jun 4 10:31:18 2014 -0700

sched/idle: Optimize try-to-wake-up IPI

commit fd99f91aa007ba255aac44fe6cf21c1db398243a
Author: Peter Zijlstra <[email protected]>
Date: Wed Apr 9 15:35:08 2014 +0200

sched/idle: Avoid spurious wakeup IPIs

They appeared in 3.16.

Thanks,

Mathieu

>
> Still beating up on my stress test, which is not yet proving to be all
> that stressful. :-/
>
> Thanx, Paul
>
>> [ 957.396537] INFO: rcu_preempt detected stalls on CPUs/tasks:
>> [ 957.399933] 1-...: (0 ticks this GP) idle=4d6/0/0 softirq=6311/6311 fqs=0
>> [ 957.403661] (detected by 0, t=60002 jiffies, g=3583, c=3582, q=47)
>> [ 957.407227] Task dump for CPU 1:
>> [ 957.409964] swapper/1 R running task 0 0 1 0x00200000
>> [ 957.413770] 0000039daa9a7eb9 ffff8801785cfed0 ffffffff818af34c
>> ffff880100000000
>> [ 957.417696] 0000000600000003 ffff8801785d0000 ffff880072f9ea00
>> ffffffff822dcf80
>> [ 957.421631] ffff8801785cc000 ffff8801785cc000 ffff8801785cfee0
>> ffffffff818af597
>> [ 957.425562] Call Trace:
>> [ 957.428124] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
>> [ 957.431713] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
>> [ 957.435122] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
>> [ 957.438467] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
>> [ 957.441949] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
>> [ 957.445378] rcu_preempt kthread starved for 60002 jiffies! g3583 c3582 f0x0
>> RCU_GP_WAIT_FQS(3) ->state=0x1
>> [ 957.449834] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
>> [ 957.453579] ffff8801785b7d68 ffff88017dc8cc80 ffff88016fe6bb80
>> ffff8801785abb80
>> [ 957.457428] ffff8801785b8000 ffff8801785b7da0 ffff88017dc8cc80
>> ffff88017dc8cc80
>> [ 957.461249] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df
>> 0000000100373021
>> [ 957.465055] Call Trace:
>> [ 957.467493] [<ffffffff81ab03df>] schedule+0x3f/0xa0
>> [ 957.470613] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
>> [ 957.473976] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
>> [ 957.477387] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
>> [ 957.480659] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
>> [ 957.484123] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
>> [ 957.487392] [<ffffffff8112f856>] kthread+0xe6/0x100
>> [ 957.490470] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
>> [ 957.493859] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
>> [ 957.497044] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
>>
> > Reinette

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-26 15:28:15

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sat, Mar 26, 2016 at 12:29:31PM +0000, Mathieu Desnoyers wrote:
> ----- On Mar 25, 2016, at 5:46 PM, Paul E. McKenney [email protected] wrote:
>
> > On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
> >> Hi Paul,
> >>
> >> On 2016-03-23, Paul E. McKenney wrote:
> >> > Please boot with the following parameters:
> >> >
> >> > rcu_tree.rcu_kick_kthreads ftrace
> >> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
> >>
> >> With these parameters I expected more details to show up in the kernel logs but
> >> cannot find any. Even so, today I left the machine running again and when this
> >> happened I think I was able to capture the trace data for the event. Please
> >> find attached the trace information for the kernel message below. Since the
> >> complete trace file is very big I trimmed it to show the time around this event
> >> - hopefully this will contain the information you need. I would also like to
> >> provide some additional information. The system on which I see these events had
> >> a time that was _very_ wrong. I noticed that this issue occurs when
> >> system-timesynd was one of the tasks calling the functions of interest to your
> >> tracing and am wondering if a very out of sync time in process of being
> >> corrected could be the cause of this issue? As an experiment I ensured the
> >> system time was accurate before leaving the system idle overnight and I did not
> >> see the issue the next morning.
> >
> > Ah! Yes, a sudden jump in time or a disagreement about the time among
> > different components of the system can definitely cause these symptoms.
> > We have sometimes seen these problems occur when a pair of CPUs have
> > wildly different ideas about what time it is, for example. Please let
> > me know how it goes.
> >
> > Also, in your trace, there are no sched_waking events for the rcu_preempt
> > process that are not immediately followed by sched_wakeup, so your trace
> > isn't showing the problem that I am seeing.
>
> This is interesting.
>
> Perhaps we could try with those commits reverted ?
>
> commit e3baac47f0e82c4be632f4f97215bb93bf16b342
> Author: Peter Zijlstra <[email protected]>
> Date: Wed Jun 4 10:31:18 2014 -0700
>
> sched/idle: Optimize try-to-wake-up IPI
>
> commit fd99f91aa007ba255aac44fe6cf21c1db398243a
> Author: Peter Zijlstra <[email protected]>
> Date: Wed Apr 9 15:35:08 2014 +0200
>
> sched/idle: Avoid spurious wakeup IPIs
>
> They appeared in 3.16.

At this point, I am up for trying pretty much anything. ;-)

Will give it a go.

Thanx, Paul

> Thanks,
>
> Mathieu
>
> >
> > Still beating up on my stress test, which is not yet proving to be all
> > that stressful. :-/
> >
> > Thanx, Paul
> >
> >> [ 957.396537] INFO: rcu_preempt detected stalls on CPUs/tasks:
> >> [ 957.399933] 1-...: (0 ticks this GP) idle=4d6/0/0 softirq=6311/6311 fqs=0
> >> [ 957.403661] (detected by 0, t=60002 jiffies, g=3583, c=3582, q=47)
> >> [ 957.407227] Task dump for CPU 1:
> >> [ 957.409964] swapper/1 R running task 0 0 1 0x00200000
> >> [ 957.413770] 0000039daa9a7eb9 ffff8801785cfed0 ffffffff818af34c
> >> ffff880100000000
> >> [ 957.417696] 0000000600000003 ffff8801785d0000 ffff880072f9ea00
> >> ffffffff822dcf80
> >> [ 957.421631] ffff8801785cc000 ffff8801785cc000 ffff8801785cfee0
> >> ffffffff818af597
> >> [ 957.425562] Call Trace:
> >> [ 957.428124] [<ffffffff818af34c>] ? cpuidle_enter_state+0xfc/0x310
> >> [ 957.431713] [<ffffffff818af597>] ? cpuidle_enter+0x17/0x20
> >> [ 957.435122] [<ffffffff811515ba>] ? call_cpuidle+0x2a/0x40
> >> [ 957.438467] [<ffffffff8115198d>] ? cpu_startup_entry+0x28d/0x360
> >> [ 957.441949] [<ffffffff8108c864>] ? start_secondary+0x114/0x140
> >> [ 957.445378] rcu_preempt kthread starved for 60002 jiffies! g3583 c3582 f0x0
> >> RCU_GP_WAIT_FQS(3) ->state=0x1
> >> [ 957.449834] rcu_preempt S ffff8801785b7d68 0 7 2 0x00000000
> >> [ 957.453579] ffff8801785b7d68 ffff88017dc8cc80 ffff88016fe6bb80
> >> ffff8801785abb80
> >> [ 957.457428] ffff8801785b8000 ffff8801785b7da0 ffff88017dc8cc80
> >> ffff88017dc8cc80
> >> [ 957.461249] 0000000000000003 ffff8801785b7d80 ffffffff81ab03df
> >> 0000000100373021
> >> [ 957.465055] Call Trace:
> >> [ 957.467493] [<ffffffff81ab03df>] schedule+0x3f/0xa0
> >> [ 957.470613] [<ffffffff81ab4397>] schedule_timeout+0x127/0x270
> >> [ 957.473976] [<ffffffff81171a00>] ? detach_if_pending+0x120/0x120
> >> [ 957.477387] [<ffffffff8116d983>] rcu_gp_kthread+0x6d3/0xa40
> >> [ 957.480659] [<ffffffff811513a0>] ? wake_atomic_t_function+0x70/0x70
> >> [ 957.484123] [<ffffffff8116d2b0>] ? force_qs_rnp+0x1b0/0x1b0
> >> [ 957.487392] [<ffffffff8112f856>] kthread+0xe6/0x100
> >> [ 957.490470] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> >> [ 957.493859] [<ffffffff81ab5ccf>] ret_from_fork+0x3f/0x70
> >> [ 957.497044] [<ffffffff8112f770>] ? kthread_worker_fn+0x190/0x190
> >>
> > > Reinette
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
>

2016-03-26 18:49:39

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sat, Mar 26, 2016 at 08:28:16AM -0700, Paul E. McKenney wrote:
> On Sat, Mar 26, 2016 at 12:29:31PM +0000, Mathieu Desnoyers wrote:
> > ----- On Mar 25, 2016, at 5:46 PM, Paul E. McKenney [email protected] wrote:
> >
> > > On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
> > >> Hi Paul,
> > >>
> > >> On 2016-03-23, Paul E. McKenney wrote:
> > >> > Please boot with the following parameters:
> > >> >
> > >> > rcu_tree.rcu_kick_kthreads ftrace
> > >> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
> > >>
> > >> With these parameters I expected more details to show up in the kernel logs but
> > >> cannot find any. Even so, today I left the machine running again and when this
> > >> happened I think I was able to capture the trace data for the event. Please
> > >> find attached the trace information for the kernel message below. Since the
> > >> complete trace file is very big I trimmed it to show the time around this event
> > >> - hopefully this will contain the information you need. I would also like to
> > >> provide some additional information. The system on which I see these events had
> > >> a time that was _very_ wrong. I noticed that this issue occurs when
> > >> system-timesynd was one of the tasks calling the functions of interest to your
> > >> tracing and am wondering if a very out of sync time in process of being
> > >> corrected could be the cause of this issue? As an experiment I ensured the
> > >> system time was accurate before leaving the system idle overnight and I did not
> > >> see the issue the next morning.
> > >
> > > Ah! Yes, a sudden jump in time or a disagreement about the time among
> > > different components of the system can definitely cause these symptoms.
> > > We have sometimes seen these problems occur when a pair of CPUs have
> > > wildly different ideas about what time it is, for example. Please let
> > > me know how it goes.
> > >
> > > Also, in your trace, there are no sched_waking events for the rcu_preempt
> > > process that are not immediately followed by sched_wakeup, so your trace
> > > isn't showing the problem that I am seeing.
> >
> > This is interesting.
> >
> > Perhaps we could try with those commits reverted ?
> >
> > commit e3baac47f0e82c4be632f4f97215bb93bf16b342
> > Author: Peter Zijlstra <[email protected]>
> > Date: Wed Jun 4 10:31:18 2014 -0700
> >
> > sched/idle: Optimize try-to-wake-up IPI
> >
> > commit fd99f91aa007ba255aac44fe6cf21c1db398243a
> > Author: Peter Zijlstra <[email protected]>
> > Date: Wed Apr 9 15:35:08 2014 +0200
> >
> > sched/idle: Avoid spurious wakeup IPIs
> >
> > They appeared in 3.16.
>
> At this point, I am up for trying pretty much anything. ;-)
>
> Will give it a go.

And those certainly don't revert cleanly! Would patching the kernel
to remove the definition of TIF_POLLING_NRFLAG be useful? Or, more
to the point, is there some other course of action that would be more
useful? At this point, the test times are measured in weeks...

Thanx, Paul

2016-03-26 22:23:06

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 26, 2016, at 2:49 PM, Paul E. McKenney [email protected] wrote:

> On Sat, Mar 26, 2016 at 08:28:16AM -0700, Paul E. McKenney wrote:
>> On Sat, Mar 26, 2016 at 12:29:31PM +0000, Mathieu Desnoyers wrote:
>> > ----- On Mar 25, 2016, at 5:46 PM, Paul E. McKenney [email protected]
>> > wrote:
>> >
>> > > On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
>> > >> Hi Paul,
>> > >>
>> > >> On 2016-03-23, Paul E. McKenney wrote:
>> > >> > Please boot with the following parameters:
>> > >> >
>> > >> > rcu_tree.rcu_kick_kthreads ftrace
>> > >> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
>> > >>
>> > >> With these parameters I expected more details to show up in the kernel logs but
>> > >> cannot find any. Even so, today I left the machine running again and when this
>> > >> happened I think I was able to capture the trace data for the event. Please
>> > >> find attached the trace information for the kernel message below. Since the
>> > >> complete trace file is very big I trimmed it to show the time around this event
>> > >> - hopefully this will contain the information you need. I would also like to
>> > >> provide some additional information. The system on which I see these events had
>> > >> a time that was _very_ wrong. I noticed that this issue occurs when
>> > >> system-timesynd was one of the tasks calling the functions of interest to your
>> > >> tracing and am wondering if a very out of sync time in process of being
>> > >> corrected could be the cause of this issue? As an experiment I ensured the
>> > >> system time was accurate before leaving the system idle overnight and I did not
>> > >> see the issue the next morning.
>> > >
>> > > Ah! Yes, a sudden jump in time or a disagreement about the time among
>> > > different components of the system can definitely cause these symptoms.
>> > > We have sometimes seen these problems occur when a pair of CPUs have
>> > > wildly different ideas about what time it is, for example. Please let
>> > > me know how it goes.
>> > >
>> > > Also, in your trace, there are no sched_waking events for the rcu_preempt
>> > > process that are not immediately followed by sched_wakeup, so your trace
>> > > isn't showing the problem that I am seeing.
>> >
>> > This is interesting.
>> >
>> > Perhaps we could try with those commits reverted ?
>> >
>> > commit e3baac47f0e82c4be632f4f97215bb93bf16b342
>> > Author: Peter Zijlstra <[email protected]>
>> > Date: Wed Jun 4 10:31:18 2014 -0700
>> >
>> > sched/idle: Optimize try-to-wake-up IPI
>> >
>> > commit fd99f91aa007ba255aac44fe6cf21c1db398243a
>> > Author: Peter Zijlstra <[email protected]>
>> > Date: Wed Apr 9 15:35:08 2014 +0200
>> >
>> > sched/idle: Avoid spurious wakeup IPIs
>> >
>> > They appeared in 3.16.
>>
>> At this point, I am up for trying pretty much anything. ;-)
>>
>> Will give it a go.
>
> And those certainly don't revert cleanly! Would patching the kernel
> to remove the definition of TIF_POLLING_NRFLAG be useful? Or, more
> to the point, is there some other course of action that would be more
> useful? At this point, the test times are measured in weeks...

Indeed, patching the kernel to remove the TIF_POLLING_NRFLAG
definition would have an effect similar to reverting those two
commits.

Since testing takes a while, we could take a more aggressive
approach towards reproducing a possible race condition: we
could re-implement the _TIF_POLLING_NRFLAG vs _TIF_NEED_RESCHED
dance, along with the ttwu pending lock-list queue, within
a dummy test module, with custom data structures, and
stress-test the invariants. We could also create a Promela
model of these ipi-skip optimisations trying to validate
progress: whenever a wakeup is requested, there should
always be a scheduling performed, even if no further wakeup
is encountered.

Each of the two approaches proposed above might be a significant
endeavor, and would only validate my specific hunch. So it might
be a good idea to just let a test run for a few weeks with
TIF_POLLING_NRFLAG disabled meanwhile.

Thoughts ?

Thanks,

Mathieu


--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-27 01:34:54

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sat, Mar 26, 2016 at 10:22:57PM +0000, Mathieu Desnoyers wrote:
> ----- On Mar 26, 2016, at 2:49 PM, Paul E. McKenney [email protected] wrote:
>
> > On Sat, Mar 26, 2016 at 08:28:16AM -0700, Paul E. McKenney wrote:
> >> On Sat, Mar 26, 2016 at 12:29:31PM +0000, Mathieu Desnoyers wrote:
> >> > ----- On Mar 25, 2016, at 5:46 PM, Paul E. McKenney [email protected]
> >> > wrote:
> >> >
> >> > > On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
> >> > >> Hi Paul,
> >> > >>
> >> > >> On 2016-03-23, Paul E. McKenney wrote:
> >> > >> > Please boot with the following parameters:
> >> > >> >
> >> > >> > rcu_tree.rcu_kick_kthreads ftrace
> >> > >> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
> >> > >>
> >> > >> With these parameters I expected more details to show up in the kernel logs but
> >> > >> cannot find any. Even so, today I left the machine running again and when this
> >> > >> happened I think I was able to capture the trace data for the event. Please
> >> > >> find attached the trace information for the kernel message below. Since the
> >> > >> complete trace file is very big I trimmed it to show the time around this event
> >> > >> - hopefully this will contain the information you need. I would also like to
> >> > >> provide some additional information. The system on which I see these events had
> >> > >> a time that was _very_ wrong. I noticed that this issue occurs when
> >> > >> system-timesynd was one of the tasks calling the functions of interest to your
> >> > >> tracing and am wondering if a very out of sync time in process of being
> >> > >> corrected could be the cause of this issue? As an experiment I ensured the
> >> > >> system time was accurate before leaving the system idle overnight and I did not
> >> > >> see the issue the next morning.
> >> > >
> >> > > Ah! Yes, a sudden jump in time or a disagreement about the time among
> >> > > different components of the system can definitely cause these symptoms.
> >> > > We have sometimes seen these problems occur when a pair of CPUs have
> >> > > wildly different ideas about what time it is, for example. Please let
> >> > > me know how it goes.
> >> > >
> >> > > Also, in your trace, there are no sched_waking events for the rcu_preempt
> >> > > process that are not immediately followed by sched_wakeup, so your trace
> >> > > isn't showing the problem that I am seeing.
> >> >
> >> > This is interesting.
> >> >
> >> > Perhaps we could try with those commits reverted ?
> >> >
> >> > commit e3baac47f0e82c4be632f4f97215bb93bf16b342
> >> > Author: Peter Zijlstra <[email protected]>
> >> > Date: Wed Jun 4 10:31:18 2014 -0700
> >> >
> >> > sched/idle: Optimize try-to-wake-up IPI
> >> >
> >> > commit fd99f91aa007ba255aac44fe6cf21c1db398243a
> >> > Author: Peter Zijlstra <[email protected]>
> >> > Date: Wed Apr 9 15:35:08 2014 +0200
> >> >
> >> > sched/idle: Avoid spurious wakeup IPIs
> >> >
> >> > They appeared in 3.16.
> >>
> >> At this point, I am up for trying pretty much anything. ;-)
> >>
> >> Will give it a go.
> >
> > And those certainly don't revert cleanly! Would patching the kernel
> > to remove the definition of TIF_POLLING_NRFLAG be useful? Or, more
> > to the point, is there some other course of action that would be more
> > useful? At this point, the test times are measured in weeks...
>
> Indeed, patching the kernel to remove the TIF_POLLING_NRFLAG
> definition would have an effect similar to reverting those two
> commits.
>
> Since testing takes a while, we could take a more aggressive
> approach towards reproducing a possible race condition: we
> could re-implement the _TIF_POLLING_NRFLAG vs _TIF_NEED_RESCHED
> dance, along with the ttwu pending lock-list queue, within
> a dummy test module, with custom data structures, and
> stress-test the invariants. We could also create a Promela
> model of these ipi-skip optimisations trying to validate
> progress: whenever a wakeup is requested, there should
> always be a scheduling performed, even if no further wakeup
> is encountered.
>
> Each of the two approaches proposed above might be a significant
> endeavor, and would only validate my specific hunch. So it might
> be a good idea to just let a test run for a few weeks with
> TIF_POLLING_NRFLAG disabled meanwhile.

This makes a lot of sense. I did some short runs, and nothing broke
too badly. However, I left some diagnostic stuff in that obscured
the outcome. I disabled the diagnostic stuff and am running overnight.
I might need to go further and revert some of my diagnostic patches,
but let's see where it is in the morning.

Thanx, Paul

2016-03-27 13:49:08

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 26, 2016, at 9:34 PM, Paul E. McKenney [email protected] wrote:

> On Sat, Mar 26, 2016 at 10:22:57PM +0000, Mathieu Desnoyers wrote:
>> ----- On Mar 26, 2016, at 2:49 PM, Paul E. McKenney [email protected]
>> wrote:
>>
>> > On Sat, Mar 26, 2016 at 08:28:16AM -0700, Paul E. McKenney wrote:
>> >> On Sat, Mar 26, 2016 at 12:29:31PM +0000, Mathieu Desnoyers wrote:
>> >> > ----- On Mar 25, 2016, at 5:46 PM, Paul E. McKenney [email protected]
>> >> > wrote:
>> >> >
>> >> > > On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
>> >> > >> Hi Paul,
>> >> > >>
>> >> > >> On 2016-03-23, Paul E. McKenney wrote:
>> >> > >> > Please boot with the following parameters:
>> >> > >> >
>> >> > >> > rcu_tree.rcu_kick_kthreads ftrace
>> >> > >> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
>> >> > >>
>> >> > >> With these parameters I expected more details to show up in the kernel logs but
>> >> > >> cannot find any. Even so, today I left the machine running again and when this
>> >> > >> happened I think I was able to capture the trace data for the event. Please
>> >> > >> find attached the trace information for the kernel message below. Since the
>> >> > >> complete trace file is very big I trimmed it to show the time around this event
>> >> > >> - hopefully this will contain the information you need. I would also like to
>> >> > >> provide some additional information. The system on which I see these events had
>> >> > >> a time that was _very_ wrong. I noticed that this issue occurs when
>> >> > >> system-timesynd was one of the tasks calling the functions of interest to your
>> >> > >> tracing and am wondering if a very out of sync time in process of being
>> >> > >> corrected could be the cause of this issue? As an experiment I ensured the
>> >> > >> system time was accurate before leaving the system idle overnight and I did not
>> >> > >> see the issue the next morning.
>> >> > >
>> >> > > Ah! Yes, a sudden jump in time or a disagreement about the time among
>> >> > > different components of the system can definitely cause these symptoms.
>> >> > > We have sometimes seen these problems occur when a pair of CPUs have
>> >> > > wildly different ideas about what time it is, for example. Please let
>> >> > > me know how it goes.
>> >> > >
>> >> > > Also, in your trace, there are no sched_waking events for the rcu_preempt
>> >> > > process that are not immediately followed by sched_wakeup, so your trace
>> >> > > isn't showing the problem that I am seeing.
>> >> >
>> >> > This is interesting.
>> >> >
>> >> > Perhaps we could try with those commits reverted ?
>> >> >
>> >> > commit e3baac47f0e82c4be632f4f97215bb93bf16b342
>> >> > Author: Peter Zijlstra <[email protected]>
>> >> > Date: Wed Jun 4 10:31:18 2014 -0700
>> >> >
>> >> > sched/idle: Optimize try-to-wake-up IPI
>> >> >
>> >> > commit fd99f91aa007ba255aac44fe6cf21c1db398243a
>> >> > Author: Peter Zijlstra <[email protected]>
>> >> > Date: Wed Apr 9 15:35:08 2014 +0200
>> >> >
>> >> > sched/idle: Avoid spurious wakeup IPIs
>> >> >
>> >> > They appeared in 3.16.
>> >>
>> >> At this point, I am up for trying pretty much anything. ;-)
>> >>
>> >> Will give it a go.
>> >
>> > And those certainly don't revert cleanly! Would patching the kernel
>> > to remove the definition of TIF_POLLING_NRFLAG be useful? Or, more
>> > to the point, is there some other course of action that would be more
>> > useful? At this point, the test times are measured in weeks...
>>
>> Indeed, patching the kernel to remove the TIF_POLLING_NRFLAG
>> definition would have an effect similar to reverting those two
>> commits.
>>
>> Since testing takes a while, we could take a more aggressive
>> approach towards reproducing a possible race condition: we
>> could re-implement the _TIF_POLLING_NRFLAG vs _TIF_NEED_RESCHED
>> dance, along with the ttwu pending lock-list queue, within
>> a dummy test module, with custom data structures, and
>> stress-test the invariants. We could also create a Promela
>> model of these ipi-skip optimisations trying to validate
>> progress: whenever a wakeup is requested, there should
>> always be a scheduling performed, even if no further wakeup
>> is encountered.
>>
>> Each of the two approaches proposed above might be a significant
>> endeavor, and would only validate my specific hunch. So it might
>> be a good idea to just let a test run for a few weeks with
>> TIF_POLLING_NRFLAG disabled meanwhile.
>
> This makes a lot of sense. I did some short runs, and nothing broke
> too badly. However, I left some diagnostic stuff in that obscured
> the outcome. I disabled the diagnostic stuff and am running overnight.
> I might need to go further and revert some of my diagnostic patches,
> but let's see where it is in the morning.

Here is another idea that might help us reproduce this issue faster.
If you can afford it, you might want to just throw more similar hardware
at the problem. Assuming the problem shows up randomly, but its odds
of showing up make it happen only once per week, if we have 100 machines
idling in the same way in parallel, we should be able to reproduce it
within about 1-2 hours.

Of course, if the problem really need each machine to "degrade" for
a week (e.g. memory fragmentation), that would not help. It's only for
races that appear to be showing up randomly.

Thoughts ?

Thanks,

Mathieu

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-27 15:40:18

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 01:48:55PM +0000, Mathieu Desnoyers wrote:
> ----- On Mar 26, 2016, at 9:34 PM, Paul E. McKenney [email protected] wrote:
>
> > On Sat, Mar 26, 2016 at 10:22:57PM +0000, Mathieu Desnoyers wrote:
> >> ----- On Mar 26, 2016, at 2:49 PM, Paul E. McKenney [email protected]
> >> wrote:
> >>
> >> > On Sat, Mar 26, 2016 at 08:28:16AM -0700, Paul E. McKenney wrote:
> >> >> On Sat, Mar 26, 2016 at 12:29:31PM +0000, Mathieu Desnoyers wrote:
> >> >> > ----- On Mar 25, 2016, at 5:46 PM, Paul E. McKenney [email protected]
> >> >> > wrote:
> >> >> >
> >> >> > > On Fri, Mar 25, 2016 at 09:24:14PM +0000, Chatre, Reinette wrote:
> >> >> > >> Hi Paul,
> >> >> > >>
> >> >> > >> On 2016-03-23, Paul E. McKenney wrote:
> >> >> > >> > Please boot with the following parameters:
> >> >> > >> >
> >> >> > >> > rcu_tree.rcu_kick_kthreads ftrace
> >> >> > >> > trace_event=sched_waking,sched_wakeup,sched_wake_idle_without_ipi
> >> >> > >>
> >> >> > >> With these parameters I expected more details to show up in the kernel logs but
> >> >> > >> cannot find any. Even so, today I left the machine running again and when this
> >> >> > >> happened I think I was able to capture the trace data for the event. Please
> >> >> > >> find attached the trace information for the kernel message below. Since the
> >> >> > >> complete trace file is very big I trimmed it to show the time around this event
> >> >> > >> - hopefully this will contain the information you need. I would also like to
> >> >> > >> provide some additional information. The system on which I see these events had
> >> >> > >> a time that was _very_ wrong. I noticed that this issue occurs when
> >> >> > >> system-timesynd was one of the tasks calling the functions of interest to your
> >> >> > >> tracing and am wondering if a very out of sync time in process of being
> >> >> > >> corrected could be the cause of this issue? As an experiment I ensured the
> >> >> > >> system time was accurate before leaving the system idle overnight and I did not
> >> >> > >> see the issue the next morning.
> >> >> > >
> >> >> > > Ah! Yes, a sudden jump in time or a disagreement about the time among
> >> >> > > different components of the system can definitely cause these symptoms.
> >> >> > > We have sometimes seen these problems occur when a pair of CPUs have
> >> >> > > wildly different ideas about what time it is, for example. Please let
> >> >> > > me know how it goes.
> >> >> > >
> >> >> > > Also, in your trace, there are no sched_waking events for the rcu_preempt
> >> >> > > process that are not immediately followed by sched_wakeup, so your trace
> >> >> > > isn't showing the problem that I am seeing.
> >> >> >
> >> >> > This is interesting.
> >> >> >
> >> >> > Perhaps we could try with those commits reverted ?
> >> >> >
> >> >> > commit e3baac47f0e82c4be632f4f97215bb93bf16b342
> >> >> > Author: Peter Zijlstra <[email protected]>
> >> >> > Date: Wed Jun 4 10:31:18 2014 -0700
> >> >> >
> >> >> > sched/idle: Optimize try-to-wake-up IPI
> >> >> >
> >> >> > commit fd99f91aa007ba255aac44fe6cf21c1db398243a
> >> >> > Author: Peter Zijlstra <[email protected]>
> >> >> > Date: Wed Apr 9 15:35:08 2014 +0200
> >> >> >
> >> >> > sched/idle: Avoid spurious wakeup IPIs
> >> >> >
> >> >> > They appeared in 3.16.
> >> >>
> >> >> At this point, I am up for trying pretty much anything. ;-)
> >> >>
> >> >> Will give it a go.
> >> >
> >> > And those certainly don't revert cleanly! Would patching the kernel
> >> > to remove the definition of TIF_POLLING_NRFLAG be useful? Or, more
> >> > to the point, is there some other course of action that would be more
> >> > useful? At this point, the test times are measured in weeks...
> >>
> >> Indeed, patching the kernel to remove the TIF_POLLING_NRFLAG
> >> definition would have an effect similar to reverting those two
> >> commits.
> >>
> >> Since testing takes a while, we could take a more aggressive
> >> approach towards reproducing a possible race condition: we
> >> could re-implement the _TIF_POLLING_NRFLAG vs _TIF_NEED_RESCHED
> >> dance, along with the ttwu pending lock-list queue, within
> >> a dummy test module, with custom data structures, and
> >> stress-test the invariants. We could also create a Promela
> >> model of these ipi-skip optimisations trying to validate
> >> progress: whenever a wakeup is requested, there should
> >> always be a scheduling performed, even if no further wakeup
> >> is encountered.
> >>
> >> Each of the two approaches proposed above might be a significant
> >> endeavor, and would only validate my specific hunch. So it might
> >> be a good idea to just let a test run for a few weeks with
> >> TIF_POLLING_NRFLAG disabled meanwhile.
> >
> > This makes a lot of sense. I did some short runs, and nothing broke
> > too badly. However, I left some diagnostic stuff in that obscured
> > the outcome. I disabled the diagnostic stuff and am running overnight.
> > I might need to go further and revert some of my diagnostic patches,
> > but let's see where it is in the morning.
>
> Here is another idea that might help us reproduce this issue faster.
> If you can afford it, you might want to just throw more similar hardware
> at the problem. Assuming the problem shows up randomly, but its odds
> of showing up make it happen only once per week, if we have 100 machines
> idling in the same way in parallel, we should be able to reproduce it
> within about 1-2 hours.
>
> Of course, if the problem really need each machine to "degrade" for
> a week (e.g. memory fragmentation), that would not help. It's only for
> races that appear to be showing up randomly.

Certain rcutorture tests sometimes hit it within an hour (TREE03).
Last night's TREE03 ran six hours without incident, which is unusual
given that I didn't enable any tracepoints, but does not any significant
level of statitstical confidence. The set will finish in a few hours,
at which point I will start parallel batches of TREE03 to see what
comes up.

Feel free to take a look at kernel/rcu/waketorture.c for my (feeble
thus far) attempt to speed things up. I am thinking that I need to
push sleeping tasks onto idle CPUs to make it happen more often.
My current approach to this is to run with CPU utilizations of about
40% and using hrtimer with a prime number of microseconds to avoid
synchronization. That should in theory get me a 40% chance of hitting
an idle CPU with a wakeup, and a reasonable chance of racing with a
CPU-hotplug operation. But maybe the wakeup needs to be remote or
some such, in which case waketorture also needs to move stuff around.

Oh, and the patch I am running with is below. I am running x86, and so
some other architectures would of course need the corresponding patch
on that architecture.

Thanx, Paul

------------------------------------------------------------------------

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index c7b5510..062ae53 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -102,7 +102,7 @@ struct thread_info {
#define TIF_FORK 18 /* ret_from_fork */
#define TIF_NOHZ 19 /* in adaptive nohz mode */
#define TIF_MEMDIE 20 /* is terminating due to OOM killer */
-#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */
+/* #define TIF_POLLING_NRFLAG 21 idle is polling for TIF_NEED_RESCHED */
#define TIF_IO_BITMAP 22 /* uses I/O bitmap */
#define TIF_FORCED_TF 24 /* true if TF in eflags artificially */
#define TIF_BLOCKSTEP 25 /* set when we want DEBUGCTLMSR_BTF */

2016-03-27 20:00:07

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
> On Sun, Mar 27, 2016 at 01:48:55PM +0000, Mathieu Desnoyers wrote:
> > ----- On Mar 26, 2016, at 9:34 PM, Paul E. McKenney [email protected] wrote:
> > > On Sat, Mar 26, 2016 at 10:22:57PM +0000, Mathieu Desnoyers wrote:
> > >> ----- On Mar 26, 2016, at 2:49 PM, Paul E. McKenney [email protected]
> > >> wrote:
> > >> > On Sat, Mar 26, 2016 at 08:28:16AM -0700, Paul E. McKenney wrote:
> > >> >> On Sat, Mar 26, 2016 at 12:29:31PM +0000, Mathieu Desnoyers wrote:

[ . . . ]

> > >> >> > Perhaps we could try with those commits reverted ?
> > >> >> >
> > >> >> > commit e3baac47f0e82c4be632f4f97215bb93bf16b342
> > >> >> > Author: Peter Zijlstra <[email protected]>
> > >> >> > Date: Wed Jun 4 10:31:18 2014 -0700
> > >> >> >
> > >> >> > sched/idle: Optimize try-to-wake-up IPI
> > >> >> >
> > >> >> > commit fd99f91aa007ba255aac44fe6cf21c1db398243a
> > >> >> > Author: Peter Zijlstra <[email protected]>
> > >> >> > Date: Wed Apr 9 15:35:08 2014 +0200
> > >> >> >
> > >> >> > sched/idle: Avoid spurious wakeup IPIs
> > >> >> >
> > >> >> > They appeared in 3.16.
> > >> >>
> > >> >> At this point, I am up for trying pretty much anything. ;-)
> > >> >>
> > >> >> Will give it a go.
> > >> >
> > >> > And those certainly don't revert cleanly! Would patching the kernel
> > >> > to remove the definition of TIF_POLLING_NRFLAG be useful? Or, more
> > >> > to the point, is there some other course of action that would be more
> > >> > useful? At this point, the test times are measured in weeks...
> > >>
> > >> Indeed, patching the kernel to remove the TIF_POLLING_NRFLAG
> > >> definition would have an effect similar to reverting those two
> > >> commits.
> > >>
> > >> Since testing takes a while, we could take a more aggressive
> > >> approach towards reproducing a possible race condition: we
> > >> could re-implement the _TIF_POLLING_NRFLAG vs _TIF_NEED_RESCHED
> > >> dance, along with the ttwu pending lock-list queue, within
> > >> a dummy test module, with custom data structures, and
> > >> stress-test the invariants. We could also create a Promela
> > >> model of these ipi-skip optimisations trying to validate
> > >> progress: whenever a wakeup is requested, there should
> > >> always be a scheduling performed, even if no further wakeup
> > >> is encountered.
> > >>
> > >> Each of the two approaches proposed above might be a significant
> > >> endeavor, and would only validate my specific hunch. So it might
> > >> be a good idea to just let a test run for a few weeks with
> > >> TIF_POLLING_NRFLAG disabled meanwhile.
> > >
> > > This makes a lot of sense. I did some short runs, and nothing broke
> > > too badly. However, I left some diagnostic stuff in that obscured
> > > the outcome. I disabled the diagnostic stuff and am running overnight.
> > > I might need to go further and revert some of my diagnostic patches,
> > > but let's see where it is in the morning.
> >
> > Here is another idea that might help us reproduce this issue faster.
> > If you can afford it, you might want to just throw more similar hardware
> > at the problem. Assuming the problem shows up randomly, but its odds
> > of showing up make it happen only once per week, if we have 100 machines
> > idling in the same way in parallel, we should be able to reproduce it
> > within about 1-2 hours.
> >
> > Of course, if the problem really need each machine to "degrade" for
> > a week (e.g. memory fragmentation), that would not help. It's only for
> > races that appear to be showing up randomly.
>
> Certain rcutorture tests sometimes hit it within an hour (TREE03).
> Last night's TREE03 ran six hours without incident, which is unusual
> given that I didn't enable any tracepoints, but does not any significant
> level of statitstical confidence. The set will finish in a few hours,
> at which point I will start parallel batches of TREE03 to see what
> comes up.
>
> Feel free to take a look at kernel/rcu/waketorture.c for my (feeble
> thus far) attempt to speed things up. I am thinking that I need to
> push sleeping tasks onto idle CPUs to make it happen more often.
> My current approach to this is to run with CPU utilizations of about
> 40% and using hrtimer with a prime number of microseconds to avoid
> synchronization. That should in theory get me a 40% chance of hitting
> an idle CPU with a wakeup, and a reasonable chance of racing with a
> CPU-hotplug operation. But maybe the wakeup needs to be remote or
> some such, in which case waketorture also needs to move stuff around.
>
> Oh, and the patch I am running with is below. I am running x86, and so
> some other architectures would of course need the corresponding patch
> on that architecture.

And it passed a full set of six-hour runs. Unusual of late, but not
unheard of. Next step is to focus on TREE03 overnight.

Thanx, Paul

2016-03-27 20:46:15

by Peter Zijlstra

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
> Oh, and the patch I am running with is below. I am running x86, and so
> some other architectures would of course need the corresponding patch
> on that architecture.

> -#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */
> +/* #define TIF_POLLING_NRFLAG 21 idle is polling for TIF_NEED_RESCHED */

x86 is the only arch that really uses this heavily IIRC.

Most of the other archs need interrupts to wake up remote cores.

So what we try to do is avoid sending IPIs when the CPU is idle, for the
remote wakeup case we use set_nr_if_polling() which sets
TIF_NEED_RESCHED if TIF_POLLING_NRFLAG was set. If it wasn't, we'll send
the IPI. Otherwise we rely on the idle loop to do sched_ttwu_pending()
when it breaks out of loop due to TIF_NEED_RESCHED.

But, you need hotplug for this to happen, right?

We should not be migrating towards, or waking on, CPUs no longer present
in cpu_active_map, and there is a rcu/sched_sync() after clearing that
bit. Furthermore, migration_call() does a sched_ttwu_pending() (waking
any remaining stragglers) before we migrate all runnable tasks off the
dying CPU.



The other interesting case would be resched_cpu(), which uses
set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
not set. If indeed not, it will send an IPI.

This assumes the idle 'exit' path will do the same as the IPI does; and
if you look at cpu_idle_loop() it does indeed do both
preempt_fold_need_resched() and sched_ttwu_pending().

Note that one cannot rely on irq_enter()/irq_exit() being called for the
scheduler IPI.

2016-03-27 20:53:37

by Peter Zijlstra

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
> Oh, and the patch I am running with is below. I am running x86, and so
> some other architectures would of course need the corresponding patch
> on that architecture.

> -#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */

Also note that ARM (v7) which Ross is running doesn't have this to begin
with.

2016-03-27 20:54:53

by Peter Zijlstra

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 21, 2016 at 09:22:30AM -0700, Jacob Pan wrote:
> > > We're seeing a similar stall (~60 seconds) on an x86 development
> > > system here. Any luck tracking down the cause of this? If not, any
> > > suggestions for traces that might be helpful?

> +Reinette, she has the system that can reproduce the issue. I
> believe she is having some other problems with it at the moment. But
> the .config should be available. Version is v4.5.

Does that system have MONITOR/MWAIT errata?

2016-03-27 21:06:37

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 10:45:59PM +0200, Peter Zijlstra wrote:
> On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
> > Oh, and the patch I am running with is below. I am running x86, and so
> > some other architectures would of course need the corresponding patch
> > on that architecture.
>
> > -#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */
> > +/* #define TIF_POLLING_NRFLAG 21 idle is polling for TIF_NEED_RESCHED */
>
> x86 is the only arch that really uses this heavily IIRC.
>
> Most of the other archs need interrupts to wake up remote cores.
>
> So what we try to do is avoid sending IPIs when the CPU is idle, for the
> remote wakeup case we use set_nr_if_polling() which sets
> TIF_NEED_RESCHED if TIF_POLLING_NRFLAG was set. If it wasn't, we'll send
> the IPI. Otherwise we rely on the idle loop to do sched_ttwu_pending()
> when it breaks out of loop due to TIF_NEED_RESCHED.
>
> But, you need hotplug for this to happen, right?

I do, but Ross Green is seeing something that looks similar, and without
CPU hotplug.

> We should not be migrating towards, or waking on, CPUs no longer present
> in cpu_active_map, and there is a rcu/sched_sync() after clearing that
> bit. Furthermore, migration_call() does a sched_ttwu_pending() (waking
> any remaining stragglers) before we migrate all runnable tasks off the
> dying CPU.

OK, so I should instrument migration_call() if I get the repro rate up?

> The other interesting case would be resched_cpu(), which uses
> set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> not set. If indeed not, it will send an IPI.
>
> This assumes the idle 'exit' path will do the same as the IPI does; and
> if you look at cpu_idle_loop() it does indeed do both
> preempt_fold_need_resched() and sched_ttwu_pending().
>
> Note that one cannot rely on irq_enter()/irq_exit() being called for the
> scheduler IPI.

OK, thank you for the info! Any specific debug actions?

Thanx, Paul

2016-03-27 21:07:34

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 10:53:18PM +0200, Peter Zijlstra wrote:
> On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
> > Oh, and the patch I am running with is below. I am running x86, and so
> > some other architectures would of course need the corresponding patch
> > on that architecture.
>
> > -#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */
>
> Also note that ARM (v7) which Ross is running doesn't have this to begin
> with.

He might well be seeing some other bug, then. Reinette might be instead
seeing time-synchronization issues, perhaps that is also Ross's problem.

Or maybe there is more than one bug. ;-)

Thanx, Paul

2016-03-27 21:09:10

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 10:54:39PM +0200, Peter Zijlstra wrote:
> On Mon, Mar 21, 2016 at 09:22:30AM -0700, Jacob Pan wrote:
> > > > We're seeing a similar stall (~60 seconds) on an x86 development
> > > > system here. Any luck tracking down the cause of this? If not, any
> > > > suggestions for traces that might be helpful?
>
> > +Reinette, she has the system that can reproduce the issue. I
> > believe she is having some other problems with it at the moment. But
> > the .config should be available. Version is v4.5.
>
> Does that system have MONITOR/MWAIT errata?

On the off-chance that this question was also directed at me, here is
what I am running on. I am running in a qemu/KVM virtual machine, in
case that matters.

Thanx, Paul

processor : 63
vendor_id : GenuineIntel
cpu family : 6
model : 47
model name : Intel(R) Xeon(R) CPU E7- 4820 @ 2.00GHz
stepping : 2
microcode : 0x37
cpu MHz : 1064.000
cache size : 18432 KB
physical id : 3
siblings : 16
core id : 25
cpu cores : 8
apicid : 243
initial apicid : 243
fpu : yes
fpu_exception : yes
cpuid level : 11
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt aes lahf_lm ida arat epb dtherm tpr_shadow vnmi flexpriority ept vpid
bogomips : 3990.01
clflush size : 64
cache_alignment : 64
address sizes : 44 bits physical, 48 bits virtual
power management:

2016-03-28 01:44:27

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 27, 2016, at 4:45 PM, Peter Zijlstra [email protected] wrote:

> On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
>> Oh, and the patch I am running with is below. I am running x86, and so
>> some other architectures would of course need the corresponding patch
>> on that architecture.
>
>> -#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */
>> +/* #define TIF_POLLING_NRFLAG 21 idle is polling for TIF_NEED_RESCHED */
>
> x86 is the only arch that really uses this heavily IIRC.
>
> Most of the other archs need interrupts to wake up remote cores.
>
> So what we try to do is avoid sending IPIs when the CPU is idle, for the
> remote wakeup case we use set_nr_if_polling() which sets
> TIF_NEED_RESCHED if TIF_POLLING_NRFLAG was set. If it wasn't, we'll send
> the IPI. Otherwise we rely on the idle loop to do sched_ttwu_pending()
> when it breaks out of loop due to TIF_NEED_RESCHED.
>
> But, you need hotplug for this to happen, right?

My understanding is that this seems to be detection of failures to be
awakened for a long time on idle CPUs. It therefore seems to be more
idle-related than cpu hotplug-related. I'm not saying that there is
no issue with hotplug, just that the investigation so far seems to
target mostly idle systems, AFAIK without stressing hotplug.

>
> We should not be migrating towards, or waking on, CPUs no longer present
> in cpu_active_map, and there is a rcu/sched_sync() after clearing that
> bit. Furthermore, migration_call() does a sched_ttwu_pending() (waking
> any remaining stragglers) before we migrate all runnable tasks off the
> dying CPU.
>
>
>
> The other interesting case would be resched_cpu(), which uses
> set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> not set. If indeed not, it will send an IPI.
>
> This assumes the idle 'exit' path will do the same as the IPI does; and
> if you look at cpu_idle_loop() it does indeed do both
> preempt_fold_need_resched() and sched_ttwu_pending().
>
> Note that one cannot rely on irq_enter()/irq_exit() being called for the
> scheduler IPI.

Looking at commit e3baac47f0e82c4be632f4f97215bb93bf16b342 :

set_nr_if_polling() returns true if the ti->flags read has the
_TIF_NEED_RESCHED bit set, which will skip the IPI.

But it seems weird. The side that calls set_nr_if_polling()
does the following:
1) llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)
2) set_nr_if_polling(rq->idle)
3) (don't do smp_send_reschedule(cpu) since set_nr_if_polling() returned
true)

The idle loop does:
1) __current_set_polling()
2) __current_clr_polling()
3) smp_mb__after_atomic()
4) sched_ttwu_pending()
5) schedule_preempt_disabled()
-> This will clear the TIF_NEED_RESCHED flag

While the idle loop is in sched_ttwu_pending(), after
it has done the llist_del_all() (thus has grabbed all the
list entries), TIF_NEED_RESCHED is still set. If both list_all and
set_nr_if_polling() are called right after the llist_del_all(), we
will end up in a situation where we have an entry in the list, but
there won't be any reschedule sent on the idle CPU until something
else awakens it. On a _very_ idle CPU, this could take some time.

set_nr_and_not_polling() don't seem to have the same issue, because
it does not return true if TIF_NEED_RESCHED is observed as being
already set: it really just depends on the state of the TIF_POLLING_NRFLAG
bit.

Am I missing something important ?

Thanks,

Mathieu

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-28 02:23:53

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 27, 2016, at 9:44 PM, Mathieu Desnoyers [email protected] wrote:

> ----- On Mar 27, 2016, at 4:45 PM, Peter Zijlstra [email protected] wrote:
>
>> On Sun, Mar 27, 2016 at 08:40:18AM -0700, Paul E. McKenney wrote:
>>> Oh, and the patch I am running with is below. I am running x86, and so
>>> some other architectures would of course need the corresponding patch
>>> on that architecture.
>>
>>> -#define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */
>>> +/* #define TIF_POLLING_NRFLAG 21 idle is polling for TIF_NEED_RESCHED */
>>
>> x86 is the only arch that really uses this heavily IIRC.
>>
>> Most of the other archs need interrupts to wake up remote cores.
>>
>> So what we try to do is avoid sending IPIs when the CPU is idle, for the
>> remote wakeup case we use set_nr_if_polling() which sets
>> TIF_NEED_RESCHED if TIF_POLLING_NRFLAG was set. If it wasn't, we'll send
>> the IPI. Otherwise we rely on the idle loop to do sched_ttwu_pending()
>> when it breaks out of loop due to TIF_NEED_RESCHED.
>>
>> But, you need hotplug for this to happen, right?
>
> My understanding is that this seems to be detection of failures to be
> awakened for a long time on idle CPUs. It therefore seems to be more
> idle-related than cpu hotplug-related. I'm not saying that there is
> no issue with hotplug, just that the investigation so far seems to
> target mostly idle systems, AFAIK without stressing hotplug.
>
>>
>> We should not be migrating towards, or waking on, CPUs no longer present
>> in cpu_active_map, and there is a rcu/sched_sync() after clearing that
>> bit. Furthermore, migration_call() does a sched_ttwu_pending() (waking
>> any remaining stragglers) before we migrate all runnable tasks off the
>> dying CPU.
>>
>>
>>
>> The other interesting case would be resched_cpu(), which uses
>> set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
>> atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
>> not set. If indeed not, it will send an IPI.
>>
>> This assumes the idle 'exit' path will do the same as the IPI does; and
>> if you look at cpu_idle_loop() it does indeed do both
>> preempt_fold_need_resched() and sched_ttwu_pending().
>>
>> Note that one cannot rely on irq_enter()/irq_exit() being called for the
>> scheduler IPI.
>
> Looking at commit e3baac47f0e82c4be632f4f97215bb93bf16b342 :
>
> set_nr_if_polling() returns true if the ti->flags read has the
> _TIF_NEED_RESCHED bit set, which will skip the IPI.
>
> But it seems weird. The side that calls set_nr_if_polling()
> does the following:
> 1) llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)
> 2) set_nr_if_polling(rq->idle)
> 3) (don't do smp_send_reschedule(cpu) since set_nr_if_polling() returned
> true)
>
> The idle loop does:
> 1) __current_set_polling()
> 2) __current_clr_polling()
> 3) smp_mb__after_atomic()
> 4) sched_ttwu_pending()
> 5) schedule_preempt_disabled()
> -> This will clear the TIF_NEED_RESCHED flag
>
> While the idle loop is in sched_ttwu_pending(), after
> it has done the llist_del_all() (thus has grabbed all the
> list entries), TIF_NEED_RESCHED is still set. If both list_all and
> set_nr_if_polling() are called right after the llist_del_all(), we
> will end up in a situation where we have an entry in the list, but
> there won't be any reschedule sent on the idle CPU until something
> else awakens it. On a _very_ idle CPU, this could take some time.
>
> set_nr_and_not_polling() don't seem to have the same issue, because
> it does not return true if TIF_NEED_RESCHED is observed as being
> already set: it really just depends on the state of the TIF_POLLING_NRFLAG
> bit.
>
> Am I missing something important ?

Well, it seems that the test for _TIF_POLLING_NRFLAG in set_nr_if_polling()
just before the test for _TIF_NEED_RESCHED should take care of it: while in
sched_ttwu_pending within the idle loop, the TIF_POLLING_NRFLAG should be
cleared, thus causing set_nr_if_polling to return false.

I'm slightly concerned about the lack of smp_mb__after_atomic()
between the TIF_NEED_RESCHED flag being cleared within schedule_preempt_disabled
and the TIF_POLLING_NRFLAG being set in the following loop. Indeed, clear_bit()
does not have a compiler barrier, nor processor-level memory barriers
(of course, the processor memory barrier should not really matter on
x86-64 due to lock prefix). Moreover, TIF_NEED_RESCHED is bit 3 on x86-64,
whereas TIF_POLLING_NRFLAG is bit 21. Those are in two different bytes of
the thread flags, and thus set/cleared as different addresses by clear_bit()
acting on an immediate "nr" argument.

If we have any state where TIF_POLLING_NRFLAG is set before TIF_NEED_RESCHED
is cleared within the idle thread, we could end up missing a needed resched IPI.

Another question: why are set_nr_if_polling and set_nr_and_not_polling two
different implementations ? Could they be combined ?

Thanks,

Mathieu


>
> Thanks,
>
> Mathieu
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-28 06:14:29

by Peter Zijlstra

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 02:23:45AM +0000, Mathieu Desnoyers wrote:

> >> But, you need hotplug for this to happen, right?
> >
> > My understanding is that this seems to be detection of failures to be
> > awakened for a long time on idle CPUs. It therefore seems to be more
> > idle-related than cpu hotplug-related. I'm not saying that there is
> > no issue with hotplug, just that the investigation so far seems to
> > target mostly idle systems, AFAIK without stressing hotplug.

Paul has stated that without hotplug he cannot trigger this.

> > set_nr_if_polling() returns true if the ti->flags read has the
> > _TIF_NEED_RESCHED bit set, which will skip the IPI.

POLLING_NR, as per your later comment

> > But it seems weird. The side that calls set_nr_if_polling()
> > does the following:
> > 1) llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)
> > 2) set_nr_if_polling(rq->idle)
> > 3) (don't do smp_send_reschedule(cpu) since set_nr_if_polling() returned
> > true)
> >
> > The idle loop does:
> > 1) __current_set_polling()
> > 2) __current_clr_polling()
> > 3) smp_mb__after_atomic()
> > 4) sched_ttwu_pending()
> > 5) schedule_preempt_disabled()
> > -> This will clear the TIF_NEED_RESCHED flag
> >
> > While the idle loop is in sched_ttwu_pending(), after
> > it has done the llist_del_all() (thus has grabbed all the
> > list entries), TIF_NEED_RESCHED is still set.

> > If both list_all and

llist_add() ?

> > set_nr_if_polling() are called right after the llist_del_all(), we
> > will end up in a situation where we have an entry in the list, but
> > there won't be any reschedule sent on the idle CPU until something
> > else awakens it. On a _very_ idle CPU, this could take some time.

Can't happen, as per clearing of POLLING_NR before doing llist_del_all()
and the latter being a full memory barrier.

> > set_nr_and_not_polling() don't seem to have the same issue, because
> > it does not return true if TIF_NEED_RESCHED is observed as being
> > already set: it really just depends on the state of the TIF_POLLING_NRFLAG
> > bit.
> >
> > Am I missing something important ?
>
> Well, it seems that the test for _TIF_POLLING_NRFLAG in set_nr_if_polling()
> just before the test for _TIF_NEED_RESCHED should take care of it: while in
> sched_ttwu_pending within the idle loop, the TIF_POLLING_NRFLAG should be
> cleared, thus causing set_nr_if_polling to return false.

Right, clue in the name: Set NEED_RESCHED _IF_ POLLING_NR (is set).

> I'm slightly concerned about the lack of smp_mb__after_atomic()
> between the TIF_NEED_RESCHED flag being cleared within schedule_preempt_disabled
> and the TIF_POLLING_NRFLAG being set in the following loop. Indeed, clear_bit()
> does not have a compiler barrier,

Urgh, it really should, as all atomic ops. set_bit() very much has a
memory clobber in, see below.

> nor processor-level memory barriers
> (of course, the processor memory barrier should not really matter on
> x86-64 due to lock prefix).

Right.

> Moreover, TIF_NEED_RESCHED is bit 3 on x86-64,
> whereas TIF_POLLING_NRFLAG is bit 21. Those are in two different bytes of
> the thread flags, and thus set/cleared as different addresses by clear_bit()
> acting on an immediate "nr" argument.
>
> If we have any state where TIF_POLLING_NRFLAG is set before TIF_NEED_RESCHED
> is cleared within the idle thread, we could end up missing a needed resched IPI.

Yes, that would be bad. No objection to adding smp_mb__before_atomic()
before the initial __current_set_polling(). Although that's not going to
make a difference for x86_64 as you already noted.

> Another question: why are set_nr_if_polling and set_nr_and_not_polling two
> different implementations ?

Because they're fundamentally two different things. The one
conditionally sets NEED_RESCHED, the other unconditionally sets it.

> Could they be combined ?

Can, yes, will not be pretty nor clear code though.


---
arch/x86/include/asm/bitops.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
index 7766d1cf096e..5345784d5e41 100644
--- a/arch/x86/include/asm/bitops.h
+++ b/arch/x86/include/asm/bitops.h
@@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
if (IS_IMMEDIATE(nr)) {
asm volatile(LOCK_PREFIX "andb %1,%0"
: CONST_MASK_ADDR(nr, addr)
- : "iq" ((u8)~CONST_MASK(nr)));
+ : "iq" ((u8)~CONST_MASK(nr))
+ : "memory");
} else {
asm volatile(LOCK_PREFIX "btr %1,%0"
: BITOP_ADDR(addr)
- : "Ir" (nr));
+ : "Ir" (nr)
+ : "memory");
}
}


2016-03-28 06:27:52

by Peter Zijlstra

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:

> > But, you need hotplug for this to happen, right?
>
> I do, but Ross Green is seeing something that looks similar, and without
> CPU hotplug.

Yes, but that's two differences so far, you need hotplug and he's on ARM
(which doesn't have TIF_POLLING_NR).

So either we're all looking at the wrong thing or these really are two
different issues.

> > We should not be migrating towards, or waking on, CPUs no longer present
> > in cpu_active_map, and there is a rcu/sched_sync() after clearing that
> > bit. Furthermore, migration_call() does a sched_ttwu_pending() (waking
> > any remaining stragglers) before we migrate all runnable tasks off the
> > dying CPU.
>
> OK, so I should instrument migration_call() if I get the repro rate up?

Can do, maybe try the below first. (yes I know how long it all takes :/)

> > The other interesting case would be resched_cpu(), which uses
> > set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> > atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> > not set. If indeed not, it will send an IPI.
> >
> > This assumes the idle 'exit' path will do the same as the IPI does; and
> > if you look at cpu_idle_loop() it does indeed do both
> > preempt_fold_need_resched() and sched_ttwu_pending().
> >
> > Note that one cannot rely on irq_enter()/irq_exit() being called for the
> > scheduler IPI.
>
> OK, thank you for the info! Any specific debug actions?

Dunno, something like the below should bring visibility into the
(lockless) wake_list thingy.

So these trace_printk()s should happen between trace_sched_waking() and
trace_sched_wakeup() (I've not fully read the thread, but ISTR you had
some traces with these here thingies on).

---
arch/x86/include/asm/bitops.h | 6 ++++--
kernel/sched/core.c | 9 +++++++++
2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
index 7766d1cf096e..5345784d5e41 100644
--- a/arch/x86/include/asm/bitops.h
+++ b/arch/x86/include/asm/bitops.h
@@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
if (IS_IMMEDIATE(nr)) {
asm volatile(LOCK_PREFIX "andb %1,%0"
: CONST_MASK_ADDR(nr, addr)
- : "iq" ((u8)~CONST_MASK(nr)));
+ : "iq" ((u8)~CONST_MASK(nr))
+ : "memory");
} else {
asm volatile(LOCK_PREFIX "btr %1,%0"
: BITOP_ADDR(addr)
- : "Ir" (nr));
+ : "Ir" (nr)
+ : "memory");
}
}

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0b21e7a724e1..b446f73c530d 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1669,6 +1669,7 @@ void sched_ttwu_pending(void)
while (llist) {
p = llist_entry(llist, struct task_struct, wake_entry);
llist = llist_next(llist);
+ trace_printk("waking %d\n", p->pid);
ttwu_do_activate(rq, p, 0);
}

@@ -1719,6 +1720,7 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
struct rq *rq = cpu_rq(cpu);

if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
+ trace_printk("queued %d for waking on %d\n", p->pid, cpu);
if (!set_nr_if_polling(rq->idle))
smp_send_reschedule(cpu);
else
@@ -5397,10 +5399,17 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
migrate_tasks(rq);
BUG_ON(rq->nr_running != 1); /* the migration thread */
raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+ /* really bad m'kay */
+ WARN_ON(!llist_empty(&rq->wake_list));
+
break;

case CPU_DEAD:
calc_load_migrate(rq);
+
+ /* more bad */
+ WARN_ON(!llist_empty(&rq->wake_list));
break;
#endif
}

2016-03-28 06:31:24

by Peter Zijlstra

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:

> > Does that system have MONITOR/MWAIT errata?
>
> On the off-chance that this question was also directed at me,

Hehe, it wasn't, however, since we're here..

> here is
> what I am running on. I am running in a qemu/KVM virtual machine, in
> case that matters.

Have you actually tried on real proper hardware? Does it still reproduce
there?

2016-03-28 13:09:12

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 08:25:47AM +0200, Peter Zijlstra wrote:
> On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:
>
> > > But, you need hotplug for this to happen, right?
> >
> > I do, but Ross Green is seeing something that looks similar, and without
> > CPU hotplug.
>
> Yes, but that's two differences so far, you need hotplug and he's on ARM
> (which doesn't have TIF_POLLING_NR).
>
> So either we're all looking at the wrong thing or these really are two
> different issues.

Given that this failure has grown more probable over the past several
releases, it does seem quite likely that we have more than one bug.
Or maybe a few bugs and additional innocent-bystander commits that make
one or more of the bugs more probable.

> > > We should not be migrating towards, or waking on, CPUs no longer present
> > > in cpu_active_map, and there is a rcu/sched_sync() after clearing that
> > > bit. Furthermore, migration_call() does a sched_ttwu_pending() (waking
> > > any remaining stragglers) before we migrate all runnable tasks off the
> > > dying CPU.
> >
> > OK, so I should instrument migration_call() if I get the repro rate up?
>
> Can do, maybe try the below first. (yes I know how long it all takes :/)

OK, will run this today, then run calibration for last night's run this
evening.

Speaking of which, last night's run (disabling TIF_POLLING_NRFLAG)
consisted of 24 two-hour runs. Six of them had hard hangs, and another
had a hang that eventually unhung of its own accord. I believe that this
is significantly fewer failures than from a stock kernel, but I could
be wrong, and it will take some serious testing to give statistical
confidence for whatever conclusion is correct.

> > > The other interesting case would be resched_cpu(), which uses
> > > set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> > > atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> > > not set. If indeed not, it will send an IPI.
> > >
> > > This assumes the idle 'exit' path will do the same as the IPI does; and
> > > if you look at cpu_idle_loop() it does indeed do both
> > > preempt_fold_need_resched() and sched_ttwu_pending().
> > >
> > > Note that one cannot rely on irq_enter()/irq_exit() being called for the
> > > scheduler IPI.
> >
> > OK, thank you for the info! Any specific debug actions?
>
> Dunno, something like the below should bring visibility into the
> (lockless) wake_list thingy.
>
> So these trace_printk()s should happen between trace_sched_waking() and
> trace_sched_wakeup() (I've not fully read the thread, but ISTR you had
> some traces with these here thingies on).
>
> ---
> arch/x86/include/asm/bitops.h | 6 ++++--
> kernel/sched/core.c | 9 +++++++++
> 2 files changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> index 7766d1cf096e..5345784d5e41 100644
> --- a/arch/x86/include/asm/bitops.h
> +++ b/arch/x86/include/asm/bitops.h
> @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> if (IS_IMMEDIATE(nr)) {
> asm volatile(LOCK_PREFIX "andb %1,%0"
> : CONST_MASK_ADDR(nr, addr)
> - : "iq" ((u8)~CONST_MASK(nr)));
> + : "iq" ((u8)~CONST_MASK(nr))
> + : "memory");
> } else {
> asm volatile(LOCK_PREFIX "btr %1,%0"
> : BITOP_ADDR(addr)
> - : "Ir" (nr));
> + : "Ir" (nr)
> + : "memory");
> }
> }

Is the above addition of "memory" strictly for the debug below, or is
it also a potential fix?

Starting it up regardless, but figured I should ask!

Thanx, Paul

> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 0b21e7a724e1..b446f73c530d 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -1669,6 +1669,7 @@ void sched_ttwu_pending(void)
> while (llist) {
> p = llist_entry(llist, struct task_struct, wake_entry);
> llist = llist_next(llist);
> + trace_printk("waking %d\n", p->pid);
> ttwu_do_activate(rq, p, 0);
> }
>
> @@ -1719,6 +1720,7 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
> struct rq *rq = cpu_rq(cpu);
>
> if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
> + trace_printk("queued %d for waking on %d\n", p->pid, cpu);
> if (!set_nr_if_polling(rq->idle))
> smp_send_reschedule(cpu);
> else
> @@ -5397,10 +5399,17 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
> migrate_tasks(rq);
> BUG_ON(rq->nr_running != 1); /* the migration thread */
> raw_spin_unlock_irqrestore(&rq->lock, flags);
> +
> + /* really bad m'kay */
> + WARN_ON(!llist_empty(&rq->wake_list));
> +
> break;
>
> case CPU_DEAD:
> calc_load_migrate(rq);
> +
> + /* more bad */
> + WARN_ON(!llist_empty(&rq->wake_list));
> break;
> #endif
> }
>

2016-03-28 13:29:33

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 08:28:51AM +0200, Peter Zijlstra wrote:
> On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:
>
> > > Does that system have MONITOR/MWAIT errata?
> >
> > On the off-chance that this question was also directed at me,
>
> Hehe, it wasn't, however, since we're here..
>
> > here is
> > what I am running on. I am running in a qemu/KVM virtual machine, in
> > case that matters.
>
> Have you actually tried on real proper hardware? Does it still reproduce
> there?

Ross has, but I have not, given that I have a shared system on the one
hand and a single-socket (four core, eight hardware thread) laptop on
the other that has even longer reproduction times. The repeat-by is
as follows:

o Build a kernel with the following Kconfigs:

CONFIG_SMP=y
CONFIG_NR_CPUS=16
CONFIG_PREEMPT_NONE=n
CONFIG_PREEMPT_VOLUNTARY=n
CONFIG_PREEMPT=y
# This should result in CONFIG_PREEMPT_RCU=y
CONFIG_HZ_PERIODIC=y
CONFIG_NO_HZ_IDLE=n
CONFIG_NO_HZ_FULL=n
CONFIG_RCU_TRACE=y
CONFIG_HOTPLUG_CPU=y
CONFIG_RCU_FANOUT=2
CONFIG_RCU_FANOUT_LEAF=2
CONFIG_RCU_NOCB_CPU=n
CONFIG_DEBUG_LOCK_ALLOC=n
CONFIG_RCU_BOOST=y
CONFIG_RCU_KTHREAD_PRIO=2
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
CONFIG_RCU_EXPERT=y
CONFIG_RCU_TORTURE_TEST=y
CONFIG_PRINTK_TIME=y
CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y

If desired, you can instead build with CONFIG_RCU_TORTURE_TEST=m
and modprobe/insmod the module manually.

o Find a two-socket x86 system or larger, with at least 16 CPUs.

o Boot the kernel with the following kernel boot parameters:

rcutorture.onoff_interval=1 rcutorture.onoff_holdoff=30

The onoff_holdoff is only needed for CONFIG_RCU_TORTURE_TEST=y.
When manually setting up the module, you get the holdoff for
free, courtesy of human timescales.

In the absence of instrumentation, I get failures usually within a
couple of hours, though sometimes much longer. With instrumentation,
the sky appears to be the limit. :-/

Ross is running on bare metal with no CPU hotplug, so perhaps his setup
is of more immediate interest. He is seeing the same symptoms that I am,
namely a task being repeatedly awakened without actually coming out of
TASK_INTERRUPTIBLE state, let alone running. As you pointed out earlier,
he cannot be seeing the same bug that my crude patch suppresses, but
given that I still see a few failures with that crude patch, it is quite
possible that there is still a common bug.

Thanx, Paul

2016-03-28 13:50:42

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 08:13:51AM +0200, Peter Zijlstra wrote:
> On Mon, Mar 28, 2016 at 02:23:45AM +0000, Mathieu Desnoyers wrote:
>
> > >> But, you need hotplug for this to happen, right?
> > >
> > > My understanding is that this seems to be detection of failures to be
> > > awakened for a long time on idle CPUs. It therefore seems to be more
> > > idle-related than cpu hotplug-related. I'm not saying that there is
> > > no issue with hotplug, just that the investigation so far seems to
> > > target mostly idle systems, AFAIK without stressing hotplug.
>
> Paul has stated that without hotplug he cannot trigger this.

Which means either that hotplug is absolutely necessary or that
hotplug increases the probability of failure. Ross's experience is
without hotplug on a mostly idle system, so I am currently betting on
"increases the probability". The set of bugs does seem to have gotten
worse somewhere between v4.1 and v4.2, but not sufficiently to allow
reasonble bisection (yes, I did try, several times).

> > > set_nr_if_polling() returns true if the ti->flags read has the
> > > _TIF_NEED_RESCHED bit set, which will skip the IPI.
>
> POLLING_NR, as per your later comment
>
> > > But it seems weird. The side that calls set_nr_if_polling()
> > > does the following:
> > > 1) llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)
> > > 2) set_nr_if_polling(rq->idle)
> > > 3) (don't do smp_send_reschedule(cpu) since set_nr_if_polling() returned
> > > true)
> > >
> > > The idle loop does:
> > > 1) __current_set_polling()
> > > 2) __current_clr_polling()
> > > 3) smp_mb__after_atomic()
> > > 4) sched_ttwu_pending()
> > > 5) schedule_preempt_disabled()
> > > -> This will clear the TIF_NEED_RESCHED flag
> > >
> > > While the idle loop is in sched_ttwu_pending(), after
> > > it has done the llist_del_all() (thus has grabbed all the
> > > list entries), TIF_NEED_RESCHED is still set.
>
> > > If both list_all and
>
> llist_add() ?
>
> > > set_nr_if_polling() are called right after the llist_del_all(), we
> > > will end up in a situation where we have an entry in the list, but
> > > there won't be any reschedule sent on the idle CPU until something
> > > else awakens it. On a _very_ idle CPU, this could take some time.
>
> Can't happen, as per clearing of POLLING_NR before doing llist_del_all()
> and the latter being a full memory barrier.
>
> > > set_nr_and_not_polling() don't seem to have the same issue, because
> > > it does not return true if TIF_NEED_RESCHED is observed as being
> > > already set: it really just depends on the state of the TIF_POLLING_NRFLAG
> > > bit.
> > >
> > > Am I missing something important ?
> >
> > Well, it seems that the test for _TIF_POLLING_NRFLAG in set_nr_if_polling()
> > just before the test for _TIF_NEED_RESCHED should take care of it: while in
> > sched_ttwu_pending within the idle loop, the TIF_POLLING_NRFLAG should be
> > cleared, thus causing set_nr_if_polling to return false.
>
> Right, clue in the name: Set NEED_RESCHED _IF_ POLLING_NR (is set).
>
> > I'm slightly concerned about the lack of smp_mb__after_atomic()
> > between the TIF_NEED_RESCHED flag being cleared within schedule_preempt_disabled
> > and the TIF_POLLING_NRFLAG being set in the following loop. Indeed, clear_bit()
> > does not have a compiler barrier,
>
> Urgh, it really should, as all atomic ops. set_bit() very much has a
> memory clobber in, see below.

And this is one of the changes in your patch that I am now testing, correct?
(Looks that way to me, but..)

Thanx, Paul

> > nor processor-level memory barriers
> > (of course, the processor memory barrier should not really matter on
> > x86-64 due to lock prefix).
>
> Right.
>
> > Moreover, TIF_NEED_RESCHED is bit 3 on x86-64,
> > whereas TIF_POLLING_NRFLAG is bit 21. Those are in two different bytes of
> > the thread flags, and thus set/cleared as different addresses by clear_bit()
> > acting on an immediate "nr" argument.
> >
> > If we have any state where TIF_POLLING_NRFLAG is set before TIF_NEED_RESCHED
> > is cleared within the idle thread, we could end up missing a needed resched IPI.
>
> Yes, that would be bad. No objection to adding smp_mb__before_atomic()
> before the initial __current_set_polling(). Although that's not going to
> make a difference for x86_64 as you already noted.
>
> > Another question: why are set_nr_if_polling and set_nr_and_not_polling two
> > different implementations ?
>
> Because they're fundamentally two different things. The one
> conditionally sets NEED_RESCHED, the other unconditionally sets it.
>
> > Could they be combined ?
>
> Can, yes, will not be pretty nor clear code though.
>
>
> ---
> arch/x86/include/asm/bitops.h | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> index 7766d1cf096e..5345784d5e41 100644
> --- a/arch/x86/include/asm/bitops.h
> +++ b/arch/x86/include/asm/bitops.h
> @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> if (IS_IMMEDIATE(nr)) {
> asm volatile(LOCK_PREFIX "andb %1,%0"
> : CONST_MASK_ADDR(nr, addr)
> - : "iq" ((u8)~CONST_MASK(nr)));
> + : "iq" ((u8)~CONST_MASK(nr))
> + : "memory");
> } else {
> asm volatile(LOCK_PREFIX "btr %1,%0"
> : BITOP_ADDR(addr)
> - : "Ir" (nr));
> + : "Ir" (nr)
> + : "memory");
> }
> }
>
>

2016-03-28 14:15:40

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 28, 2016, at 2:13 AM, Peter Zijlstra [email protected] wrote:

> On Mon, Mar 28, 2016 at 02:23:45AM +0000, Mathieu Desnoyers wrote:
>
>> >> But, you need hotplug for this to happen, right?
>> >
>> > My understanding is that this seems to be detection of failures to be
>> > awakened for a long time on idle CPUs. It therefore seems to be more
>> > idle-related than cpu hotplug-related. I'm not saying that there is
>> > no issue with hotplug, just that the investigation so far seems to
>> > target mostly idle systems, AFAIK without stressing hotplug.
>
> Paul has stated that without hotplug he cannot trigger this.
>
>> > set_nr_if_polling() returns true if the ti->flags read has the
>> > _TIF_NEED_RESCHED bit set, which will skip the IPI.
>
> POLLING_NR, as per your later comment
>
>> > But it seems weird. The side that calls set_nr_if_polling()
>> > does the following:
>> > 1) llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)
>> > 2) set_nr_if_polling(rq->idle)
>> > 3) (don't do smp_send_reschedule(cpu) since set_nr_if_polling() returned
>> > true)
>> >
>> > The idle loop does:
>> > 1) __current_set_polling()
>> > 2) __current_clr_polling()
>> > 3) smp_mb__after_atomic()
>> > 4) sched_ttwu_pending()
>> > 5) schedule_preempt_disabled()
>> > -> This will clear the TIF_NEED_RESCHED flag
>> >
>> > While the idle loop is in sched_ttwu_pending(), after
>> > it has done the llist_del_all() (thus has grabbed all the
>> > list entries), TIF_NEED_RESCHED is still set.
>
>> > If both list_all and
>
> llist_add() ?

Yes, indeed.

>
>> > set_nr_if_polling() are called right after the llist_del_all(), we
>> > will end up in a situation where we have an entry in the list, but
>> > there won't be any reschedule sent on the idle CPU until something
>> > else awakens it. On a _very_ idle CPU, this could take some time.
>
> Can't happen, as per clearing of POLLING_NR before doing llist_del_all()
> and the latter being a full memory barrier.
>
>> > set_nr_and_not_polling() don't seem to have the same issue, because
>> > it does not return true if TIF_NEED_RESCHED is observed as being
>> > already set: it really just depends on the state of the TIF_POLLING_NRFLAG
>> > bit.
>> >
>> > Am I missing something important ?
>>
>> Well, it seems that the test for _TIF_POLLING_NRFLAG in set_nr_if_polling()
>> just before the test for _TIF_NEED_RESCHED should take care of it: while in
>> sched_ttwu_pending within the idle loop, the TIF_POLLING_NRFLAG should be
>> cleared, thus causing set_nr_if_polling to return false.
>
> Right, clue in the name: Set NEED_RESCHED _IF_ POLLING_NR (is set).
>
>> I'm slightly concerned about the lack of smp_mb__after_atomic()
>> between the TIF_NEED_RESCHED flag being cleared within schedule_preempt_disabled
>> and the TIF_POLLING_NRFLAG being set in the following loop. Indeed, clear_bit()
>> does not have a compiler barrier,
>
> Urgh, it really should, as all atomic ops. set_bit() very much has a
> memory clobber in, see below.

Yes, I'd be more comfortable with the memory clobber in the clear_bit
too, but theoretically it *should* not matter, because we have a clobber
in set_bit, and clear_bit has a +m memory operand.

>
>> nor processor-level memory barriers
>> (of course, the processor memory barrier should not really matter on
>> x86-64 due to lock prefix).
>
> Right.
>
>> Moreover, TIF_NEED_RESCHED is bit 3 on x86-64,
>> whereas TIF_POLLING_NRFLAG is bit 21. Those are in two different bytes of
>> the thread flags, and thus set/cleared as different addresses by clear_bit()
>> acting on an immediate "nr" argument.
>>
>> If we have any state where TIF_POLLING_NRFLAG is set before TIF_NEED_RESCHED
>> is cleared within the idle thread, we could end up missing a needed resched IPI.
>
> Yes, that would be bad. No objection to adding smp_mb__before_atomic()
> before the initial __current_set_polling(). Although that's not going to
> make a difference for x86_64 as you already noted.

Yep.

>
>> Another question: why are set_nr_if_polling and set_nr_and_not_polling two
>> different implementations ?
>
> Because they're fundamentally two different things. The one
> conditionally sets NEED_RESCHED, the other unconditionally sets it.

Got it, makes sense.

Thanks!

Mathieu

>
>> Could they be combined ?
>
> Can, yes, will not be pretty nor clear code though.
>
>
> ---
> arch/x86/include/asm/bitops.h | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> index 7766d1cf096e..5345784d5e41 100644
> --- a/arch/x86/include/asm/bitops.h
> +++ b/arch/x86/include/asm/bitops.h
> @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> if (IS_IMMEDIATE(nr)) {
> asm volatile(LOCK_PREFIX "andb %1,%0"
> : CONST_MASK_ADDR(nr, addr)
> - : "iq" ((u8)~CONST_MASK(nr)));
> + : "iq" ((u8)~CONST_MASK(nr))
> + : "memory");
> } else {
> asm volatile(LOCK_PREFIX "btr %1,%0"
> : BITOP_ADDR(addr)
> - : "Ir" (nr));
> + : "Ir" (nr)
> + : "memory");
> }
> }

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-28 15:07:44

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 28, 2016, at 9:29 AM, Paul E. McKenney [email protected] wrote:

> On Mon, Mar 28, 2016 at 08:28:51AM +0200, Peter Zijlstra wrote:
>> On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:
>>
>> > > Does that system have MONITOR/MWAIT errata?
>> >
>> > On the off-chance that this question was also directed at me,
>>
>> Hehe, it wasn't, however, since we're here..
>>
>> > here is
>> > what I am running on. I am running in a qemu/KVM virtual machine, in
>> > case that matters.
>>
>> Have you actually tried on real proper hardware? Does it still reproduce
>> there?
>
> Ross has, but I have not, given that I have a shared system on the one
> hand and a single-socket (four core, eight hardware thread) laptop on
> the other that has even longer reproduction times. The repeat-by is
> as follows:
>
> o Build a kernel with the following Kconfigs:
>
> CONFIG_SMP=y
> CONFIG_NR_CPUS=16
> CONFIG_PREEMPT_NONE=n
> CONFIG_PREEMPT_VOLUNTARY=n
> CONFIG_PREEMPT=y
> # This should result in CONFIG_PREEMPT_RCU=y
> CONFIG_HZ_PERIODIC=y
> CONFIG_NO_HZ_IDLE=n
> CONFIG_NO_HZ_FULL=n
> CONFIG_RCU_TRACE=y
> CONFIG_HOTPLUG_CPU=y
> CONFIG_RCU_FANOUT=2
> CONFIG_RCU_FANOUT_LEAF=2
> CONFIG_RCU_NOCB_CPU=n
> CONFIG_DEBUG_LOCK_ALLOC=n
> CONFIG_RCU_BOOST=y
> CONFIG_RCU_KTHREAD_PRIO=2
> CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
> CONFIG_RCU_EXPERT=y
> CONFIG_RCU_TORTURE_TEST=y
> CONFIG_PRINTK_TIME=y
> CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
> CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
> CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y
>
> If desired, you can instead build with CONFIG_RCU_TORTURE_TEST=m
> and modprobe/insmod the module manually.
>
> o Find a two-socket x86 system or larger, with at least 16 CPUs.
>
> o Boot the kernel with the following kernel boot parameters:
>
> rcutorture.onoff_interval=1 rcutorture.onoff_holdoff=30
>
> The onoff_holdoff is only needed for CONFIG_RCU_TORTURE_TEST=y.
> When manually setting up the module, you get the holdoff for
> free, courtesy of human timescales.
>
> In the absence of instrumentation, I get failures usually within a
> couple of hours, though sometimes much longer. With instrumentation,
> the sky appears to be the limit. :-/
>
> Ross is running on bare metal with no CPU hotplug, so perhaps his setup
> is of more immediate interest. He is seeing the same symptoms that I am,
> namely a task being repeatedly awakened without actually coming out of
> TASK_INTERRUPTIBLE state, let alone running. As you pointed out earlier,
> he cannot be seeing the same bug that my crude patch suppresses, but
> given that I still see a few failures with that crude patch, it is quite
> possible that there is still a common bug.

With respect to bare metal vs KVM guest, I've reported an issue with
inaccurate detection of TSC as being an unreliable time source on a
KVM guest. The basic setup is to overcommit the CPU use across the
entire host, thus leading to preemption of the guest. The guest TSC
watchdog then falsely assume that TSC is unreliable, because it gets
preempted for a long time (e.g. 0.5 second) between reading the HPET
and the TSC.

Ref. http://lkml.iu.edu/hypermail/linux/kernel/1509.1/00379.html

I'm wondering if what Paul is observing in the KVM setup might be
caused by long preemption by the host. One way to stress test this
is to run parallel kernel builds on the host (or in another guest)
while the guest is running, thus over-committing the CPU use.

Thoughts ?

Thanks,

Mathieu

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-28 16:00:29

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 03:07:36PM +0000, Mathieu Desnoyers wrote:
> ----- On Mar 28, 2016, at 9:29 AM, Paul E. McKenney [email protected] wrote:
>
> > On Mon, Mar 28, 2016 at 08:28:51AM +0200, Peter Zijlstra wrote:
> >> On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:
> >>
> >> > > Does that system have MONITOR/MWAIT errata?
> >> >
> >> > On the off-chance that this question was also directed at me,
> >>
> >> Hehe, it wasn't, however, since we're here..
> >>
> >> > here is
> >> > what I am running on. I am running in a qemu/KVM virtual machine, in
> >> > case that matters.
> >>
> >> Have you actually tried on real proper hardware? Does it still reproduce
> >> there?
> >
> > Ross has, but I have not, given that I have a shared system on the one
> > hand and a single-socket (four core, eight hardware thread) laptop on
> > the other that has even longer reproduction times. The repeat-by is
> > as follows:
> >
> > o Build a kernel with the following Kconfigs:
> >
> > CONFIG_SMP=y
> > CONFIG_NR_CPUS=16
> > CONFIG_PREEMPT_NONE=n
> > CONFIG_PREEMPT_VOLUNTARY=n
> > CONFIG_PREEMPT=y
> > # This should result in CONFIG_PREEMPT_RCU=y
> > CONFIG_HZ_PERIODIC=y
> > CONFIG_NO_HZ_IDLE=n
> > CONFIG_NO_HZ_FULL=n
> > CONFIG_RCU_TRACE=y
> > CONFIG_HOTPLUG_CPU=y
> > CONFIG_RCU_FANOUT=2
> > CONFIG_RCU_FANOUT_LEAF=2
> > CONFIG_RCU_NOCB_CPU=n
> > CONFIG_DEBUG_LOCK_ALLOC=n
> > CONFIG_RCU_BOOST=y
> > CONFIG_RCU_KTHREAD_PRIO=2
> > CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
> > CONFIG_RCU_EXPERT=y
> > CONFIG_RCU_TORTURE_TEST=y
> > CONFIG_PRINTK_TIME=y
> > CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
> > CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
> > CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y
> >
> > If desired, you can instead build with CONFIG_RCU_TORTURE_TEST=m
> > and modprobe/insmod the module manually.
> >
> > o Find a two-socket x86 system or larger, with at least 16 CPUs.
> >
> > o Boot the kernel with the following kernel boot parameters:
> >
> > rcutorture.onoff_interval=1 rcutorture.onoff_holdoff=30
> >
> > The onoff_holdoff is only needed for CONFIG_RCU_TORTURE_TEST=y.
> > When manually setting up the module, you get the holdoff for
> > free, courtesy of human timescales.
> >
> > In the absence of instrumentation, I get failures usually within a
> > couple of hours, though sometimes much longer. With instrumentation,
> > the sky appears to be the limit. :-/
> >
> > Ross is running on bare metal with no CPU hotplug, so perhaps his setup
> > is of more immediate interest. He is seeing the same symptoms that I am,
> > namely a task being repeatedly awakened without actually coming out of
> > TASK_INTERRUPTIBLE state, let alone running. As you pointed out earlier,
> > he cannot be seeing the same bug that my crude patch suppresses, but
> > given that I still see a few failures with that crude patch, it is quite
> > possible that there is still a common bug.
>
> With respect to bare metal vs KVM guest, I've reported an issue with
> inaccurate detection of TSC as being an unreliable time source on a
> KVM guest. The basic setup is to overcommit the CPU use across the
> entire host, thus leading to preemption of the guest. The guest TSC
> watchdog then falsely assume that TSC is unreliable, because it gets
> preempted for a long time (e.g. 0.5 second) between reading the HPET
> and the TSC.
>
> Ref. http://lkml.iu.edu/hypermail/linux/kernel/1509.1/00379.html
>
> I'm wondering if what Paul is observing in the KVM setup might be
> caused by long preemption by the host. One way to stress test this
> is to run parallel kernel builds on the host (or in another guest)
> while the guest is running, thus over-committing the CPU use.
>
> Thoughts ?

If I run NO_HZ_FULL, I do get warnings about unstable timesources.

And certainly guest VCPUs can be preempted. However, if they were
preempted for the lengths of time I am seeing, I should also see
softlockup warnings on the host, which I do not see.

That said, perhaps I should cobble together something to force short
repeated preemptions at the host level. Maybe that would get the
reproduction rate sufficiently high to enable less-dainty debugging.

Thanx, Paul

2016-03-28 16:12:30

by Mathieu Desnoyers

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

----- On Mar 28, 2016, at 11:56 AM, Paul E. McKenney [email protected] wrote:

> On Mon, Mar 28, 2016 at 03:07:36PM +0000, Mathieu Desnoyers wrote:
>> ----- On Mar 28, 2016, at 9:29 AM, Paul E. McKenney [email protected]
>> wrote:
>>
>> > On Mon, Mar 28, 2016 at 08:28:51AM +0200, Peter Zijlstra wrote:
>> >> On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:
>> >>
>> >> > > Does that system have MONITOR/MWAIT errata?
>> >> >
>> >> > On the off-chance that this question was also directed at me,
>> >>
>> >> Hehe, it wasn't, however, since we're here..
>> >>
>> >> > here is
>> >> > what I am running on. I am running in a qemu/KVM virtual machine, in
>> >> > case that matters.
>> >>
>> >> Have you actually tried on real proper hardware? Does it still reproduce
>> >> there?
>> >
>> > Ross has, but I have not, given that I have a shared system on the one
>> > hand and a single-socket (four core, eight hardware thread) laptop on
>> > the other that has even longer reproduction times. The repeat-by is
>> > as follows:
>> >
>> > o Build a kernel with the following Kconfigs:
>> >
>> > CONFIG_SMP=y
>> > CONFIG_NR_CPUS=16
>> > CONFIG_PREEMPT_NONE=n
>> > CONFIG_PREEMPT_VOLUNTARY=n
>> > CONFIG_PREEMPT=y
>> > # This should result in CONFIG_PREEMPT_RCU=y
>> > CONFIG_HZ_PERIODIC=y
>> > CONFIG_NO_HZ_IDLE=n
>> > CONFIG_NO_HZ_FULL=n
>> > CONFIG_RCU_TRACE=y
>> > CONFIG_HOTPLUG_CPU=y
>> > CONFIG_RCU_FANOUT=2
>> > CONFIG_RCU_FANOUT_LEAF=2
>> > CONFIG_RCU_NOCB_CPU=n
>> > CONFIG_DEBUG_LOCK_ALLOC=n
>> > CONFIG_RCU_BOOST=y
>> > CONFIG_RCU_KTHREAD_PRIO=2
>> > CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
>> > CONFIG_RCU_EXPERT=y
>> > CONFIG_RCU_TORTURE_TEST=y
>> > CONFIG_PRINTK_TIME=y
>> > CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
>> > CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
>> > CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y
>> >
>> > If desired, you can instead build with CONFIG_RCU_TORTURE_TEST=m
>> > and modprobe/insmod the module manually.
>> >
>> > o Find a two-socket x86 system or larger, with at least 16 CPUs.
>> >
>> > o Boot the kernel with the following kernel boot parameters:
>> >
>> > rcutorture.onoff_interval=1 rcutorture.onoff_holdoff=30
>> >
>> > The onoff_holdoff is only needed for CONFIG_RCU_TORTURE_TEST=y.
>> > When manually setting up the module, you get the holdoff for
>> > free, courtesy of human timescales.
>> >
>> > In the absence of instrumentation, I get failures usually within a
>> > couple of hours, though sometimes much longer. With instrumentation,
>> > the sky appears to be the limit. :-/
>> >
>> > Ross is running on bare metal with no CPU hotplug, so perhaps his setup
>> > is of more immediate interest. He is seeing the same symptoms that I am,
>> > namely a task being repeatedly awakened without actually coming out of
>> > TASK_INTERRUPTIBLE state, let alone running. As you pointed out earlier,
>> > he cannot be seeing the same bug that my crude patch suppresses, but
>> > given that I still see a few failures with that crude patch, it is quite
>> > possible that there is still a common bug.
>>
>> With respect to bare metal vs KVM guest, I've reported an issue with
>> inaccurate detection of TSC as being an unreliable time source on a
>> KVM guest. The basic setup is to overcommit the CPU use across the
>> entire host, thus leading to preemption of the guest. The guest TSC
>> watchdog then falsely assume that TSC is unreliable, because it gets
>> preempted for a long time (e.g. 0.5 second) between reading the HPET
>> and the TSC.
>>
>> Ref. http://lkml.iu.edu/hypermail/linux/kernel/1509.1/00379.html
>>
>> I'm wondering if what Paul is observing in the KVM setup might be
>> caused by long preemption by the host. One way to stress test this
>> is to run parallel kernel builds on the host (or in another guest)
>> while the guest is running, thus over-committing the CPU use.
>>
>> Thoughts ?
>
> If I run NO_HZ_FULL, I do get warnings about unstable timesources.
>
> And certainly guest VCPUs can be preempted. However, if they were
> preempted for the lengths of time I am seeing, I should also see
> softlockup warnings on the host, which I do not see.

Why would you see softlockup warning on the host ?

I expect the priority at which the kvm vcpu runs is much lower than
the priority of the rcu worker threads on the host. Therefore, you
might very well have long preemption delays for kvm vpus while the
rcu worker threads run fine on the host kernel because they have
a higher priority.

Am I missing something ?

Thanks,

Mathieu

>
> That said, perhaps I should cobble together something to force short
> repeated preemptions at the host level. Maybe that would get the
> reproduction rate sufficiently high to enable less-dainty debugging.
>
> Thanx, Paul

--
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com

2016-03-28 16:29:56

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 04:12:19PM +0000, Mathieu Desnoyers wrote:
> ----- On Mar 28, 2016, at 11:56 AM, Paul E. McKenney [email protected] wrote:
>
> > On Mon, Mar 28, 2016 at 03:07:36PM +0000, Mathieu Desnoyers wrote:
> >> ----- On Mar 28, 2016, at 9:29 AM, Paul E. McKenney [email protected]
> >> wrote:
> >>
> >> > On Mon, Mar 28, 2016 at 08:28:51AM +0200, Peter Zijlstra wrote:
> >> >> On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:
> >> >>
> >> >> > > Does that system have MONITOR/MWAIT errata?
> >> >> >
> >> >> > On the off-chance that this question was also directed at me,
> >> >>
> >> >> Hehe, it wasn't, however, since we're here..
> >> >>
> >> >> > here is
> >> >> > what I am running on. I am running in a qemu/KVM virtual machine, in
> >> >> > case that matters.
> >> >>
> >> >> Have you actually tried on real proper hardware? Does it still reproduce
> >> >> there?
> >> >
> >> > Ross has, but I have not, given that I have a shared system on the one
> >> > hand and a single-socket (four core, eight hardware thread) laptop on
> >> > the other that has even longer reproduction times. The repeat-by is
> >> > as follows:
> >> >
> >> > o Build a kernel with the following Kconfigs:
> >> >
> >> > CONFIG_SMP=y
> >> > CONFIG_NR_CPUS=16
> >> > CONFIG_PREEMPT_NONE=n
> >> > CONFIG_PREEMPT_VOLUNTARY=n
> >> > CONFIG_PREEMPT=y
> >> > # This should result in CONFIG_PREEMPT_RCU=y
> >> > CONFIG_HZ_PERIODIC=y
> >> > CONFIG_NO_HZ_IDLE=n
> >> > CONFIG_NO_HZ_FULL=n
> >> > CONFIG_RCU_TRACE=y
> >> > CONFIG_HOTPLUG_CPU=y
> >> > CONFIG_RCU_FANOUT=2
> >> > CONFIG_RCU_FANOUT_LEAF=2
> >> > CONFIG_RCU_NOCB_CPU=n
> >> > CONFIG_DEBUG_LOCK_ALLOC=n
> >> > CONFIG_RCU_BOOST=y
> >> > CONFIG_RCU_KTHREAD_PRIO=2
> >> > CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
> >> > CONFIG_RCU_EXPERT=y
> >> > CONFIG_RCU_TORTURE_TEST=y
> >> > CONFIG_PRINTK_TIME=y
> >> > CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
> >> > CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
> >> > CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y
> >> >
> >> > If desired, you can instead build with CONFIG_RCU_TORTURE_TEST=m
> >> > and modprobe/insmod the module manually.
> >> >
> >> > o Find a two-socket x86 system or larger, with at least 16 CPUs.
> >> >
> >> > o Boot the kernel with the following kernel boot parameters:
> >> >
> >> > rcutorture.onoff_interval=1 rcutorture.onoff_holdoff=30
> >> >
> >> > The onoff_holdoff is only needed for CONFIG_RCU_TORTURE_TEST=y.
> >> > When manually setting up the module, you get the holdoff for
> >> > free, courtesy of human timescales.
> >> >
> >> > In the absence of instrumentation, I get failures usually within a
> >> > couple of hours, though sometimes much longer. With instrumentation,
> >> > the sky appears to be the limit. :-/
> >> >
> >> > Ross is running on bare metal with no CPU hotplug, so perhaps his setup
> >> > is of more immediate interest. He is seeing the same symptoms that I am,
> >> > namely a task being repeatedly awakened without actually coming out of
> >> > TASK_INTERRUPTIBLE state, let alone running. As you pointed out earlier,
> >> > he cannot be seeing the same bug that my crude patch suppresses, but
> >> > given that I still see a few failures with that crude patch, it is quite
> >> > possible that there is still a common bug.
> >>
> >> With respect to bare metal vs KVM guest, I've reported an issue with
> >> inaccurate detection of TSC as being an unreliable time source on a
> >> KVM guest. The basic setup is to overcommit the CPU use across the
> >> entire host, thus leading to preemption of the guest. The guest TSC
> >> watchdog then falsely assume that TSC is unreliable, because it gets
> >> preempted for a long time (e.g. 0.5 second) between reading the HPET
> >> and the TSC.
> >>
> >> Ref. http://lkml.iu.edu/hypermail/linux/kernel/1509.1/00379.html
> >>
> >> I'm wondering if what Paul is observing in the KVM setup might be
> >> caused by long preemption by the host. One way to stress test this
> >> is to run parallel kernel builds on the host (or in another guest)
> >> while the guest is running, thus over-committing the CPU use.
> >>
> >> Thoughts ?
> >
> > If I run NO_HZ_FULL, I do get warnings about unstable timesources.
> >
> > And certainly guest VCPUs can be preempted. However, if they were
> > preempted for the lengths of time I am seeing, I should also see
> > softlockup warnings on the host, which I do not see.
>
> Why would you see softlockup warning on the host ?
>
> I expect the priority at which the kvm vcpu runs is much lower than
> the priority of the rcu worker threads on the host. Therefore, you
> might very well have long preemption delays for kvm vpus while the
> rcu worker threads run fine on the host kernel because they have
> a higher priority.
>
> Am I missing something ?

Right, host/guest confusion on my part. I should expect softlockups
on the -guest- because rcutorture runs almost entirely in kernel
mode. I don't see them there, either.

Another reason I do not expect preemption is the problem is because
I don't see it with waketorture, which has a large number of tasks
periodically waking up.

Yet another reason is that I can get things moving again by doing periodic
wakeups from the scheduling-clock interrupt. (Why those wakeups make
things go but those from the timers don't is a mystery to me!) Please see
commit 56ef96ac25c3 (DIAGS: Another horrible exploratory hack) for one
piece of this. This would presumably have no effect on preemption at
the host level.

Thanx, Paul

> Thanks,
>
> Mathieu
>
> >
> > That said, perhaps I should cobble together something to force short
> > repeated preemptions at the host level. Maybe that would get the
> > reproduction rate sufficiently high to enable less-dainty debugging.
> >
> > Thanx, Paul
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
>

2016-03-29 00:25:16

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 06:08:41AM -0700, Paul E. McKenney wrote:
> On Mon, Mar 28, 2016 at 08:25:47AM +0200, Peter Zijlstra wrote:
> > On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:

[ . . . ]

> > > OK, so I should instrument migration_call() if I get the repro rate up?
> >
> > Can do, maybe try the below first. (yes I know how long it all takes :/)
>
> OK, will run this today, then run calibration for last night's run this
> evening.

And there was one failure out of ten runs. If last night's failure rate
was typical (7 of 24), then I believe we can be about 87% confident that
this change helped. That isn't all that confident, but...

Tested-by: Paul E. McKenney <[email protected]>

So what to run tonight?

The most sane approach would be to run stock in order to get a baseline
failure rate. It is tempting to run more of Peter's patch, but part of
the problem is that we don't know the current baseline.

So baseline it is...

Thanx, Paul

> Speaking of which, last night's run (disabling TIF_POLLING_NRFLAG)
> consisted of 24 two-hour runs. Six of them had hard hangs, and another
> had a hang that eventually unhung of its own accord. I believe that this
> is significantly fewer failures than from a stock kernel, but I could
> be wrong, and it will take some serious testing to give statistical
> confidence for whatever conclusion is correct.
>
> > > > The other interesting case would be resched_cpu(), which uses
> > > > set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> > > > atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> > > > not set. If indeed not, it will send an IPI.
> > > >
> > > > This assumes the idle 'exit' path will do the same as the IPI does; and
> > > > if you look at cpu_idle_loop() it does indeed do both
> > > > preempt_fold_need_resched() and sched_ttwu_pending().
> > > >
> > > > Note that one cannot rely on irq_enter()/irq_exit() being called for the
> > > > scheduler IPI.
> > >
> > > OK, thank you for the info! Any specific debug actions?
> >
> > Dunno, something like the below should bring visibility into the
> > (lockless) wake_list thingy.
> >
> > So these trace_printk()s should happen between trace_sched_waking() and
> > trace_sched_wakeup() (I've not fully read the thread, but ISTR you had
> > some traces with these here thingies on).
> >
> > ---
> > arch/x86/include/asm/bitops.h | 6 ++++--
> > kernel/sched/core.c | 9 +++++++++
> > 2 files changed, 13 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> > index 7766d1cf096e..5345784d5e41 100644
> > --- a/arch/x86/include/asm/bitops.h
> > +++ b/arch/x86/include/asm/bitops.h
> > @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> > if (IS_IMMEDIATE(nr)) {
> > asm volatile(LOCK_PREFIX "andb %1,%0"
> > : CONST_MASK_ADDR(nr, addr)
> > - : "iq" ((u8)~CONST_MASK(nr)));
> > + : "iq" ((u8)~CONST_MASK(nr))
> > + : "memory");
> > } else {
> > asm volatile(LOCK_PREFIX "btr %1,%0"
> > : BITOP_ADDR(addr)
> > - : "Ir" (nr));
> > + : "Ir" (nr)
> > + : "memory");
> > }
> > }
>
> Is the above addition of "memory" strictly for the debug below, or is
> it also a potential fix?
>
> Starting it up regardless, but figured I should ask!
>
> Thanx, Paul
>
> > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > index 0b21e7a724e1..b446f73c530d 100644
> > --- a/kernel/sched/core.c
> > +++ b/kernel/sched/core.c
> > @@ -1669,6 +1669,7 @@ void sched_ttwu_pending(void)
> > while (llist) {
> > p = llist_entry(llist, struct task_struct, wake_entry);
> > llist = llist_next(llist);
> > + trace_printk("waking %d\n", p->pid);
> > ttwu_do_activate(rq, p, 0);
> > }
> >
> > @@ -1719,6 +1720,7 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
> > struct rq *rq = cpu_rq(cpu);
> >
> > if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
> > + trace_printk("queued %d for waking on %d\n", p->pid, cpu);
> > if (!set_nr_if_polling(rq->idle))
> > smp_send_reschedule(cpu);
> > else
> > @@ -5397,10 +5399,17 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
> > migrate_tasks(rq);
> > BUG_ON(rq->nr_running != 1); /* the migration thread */
> > raw_spin_unlock_irqrestore(&rq->lock, flags);
> > +
> > + /* really bad m'kay */
> > + WARN_ON(!llist_empty(&rq->wake_list));
> > +
> > break;
> >
> > case CPU_DEAD:
> > calc_load_migrate(rq);
> > +
> > + /* more bad */
> > + WARN_ON(!llist_empty(&rq->wake_list));
> > break;
> > #endif
> > }
> >

2016-03-29 00:28:11

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 05:25:18PM -0700, Paul E. McKenney wrote:
> On Mon, Mar 28, 2016 at 06:08:41AM -0700, Paul E. McKenney wrote:
> > On Mon, Mar 28, 2016 at 08:25:47AM +0200, Peter Zijlstra wrote:
> > > On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:
>
> [ . . . ]
>
> > > > OK, so I should instrument migration_call() if I get the repro rate up?
> > >
> > > Can do, maybe try the below first. (yes I know how long it all takes :/)
> >
> > OK, will run this today, then run calibration for last night's run this
> > evening.
>
> And there was one failure out of ten runs. If last night's failure rate
> was typical (7 of 24), then I believe we can be about 87% confident that
> this change helped. That isn't all that confident, but...

And, as Murphy would have it, the instrumentation didn't trigger. I just
got the usual stall-warning messages with a starving RCU grace-period
kthread.

Thanx, Paul

> Tested-by: Paul E. McKenney <[email protected]>
>
> So what to run tonight?
>
> The most sane approach would be to run stock in order to get a baseline
> failure rate. It is tempting to run more of Peter's patch, but part of
> the problem is that we don't know the current baseline.
>
> So baseline it is...
>
> Thanx, Paul
>
> > Speaking of which, last night's run (disabling TIF_POLLING_NRFLAG)
> > consisted of 24 two-hour runs. Six of them had hard hangs, and another
> > had a hang that eventually unhung of its own accord. I believe that this
> > is significantly fewer failures than from a stock kernel, but I could
> > be wrong, and it will take some serious testing to give statistical
> > confidence for whatever conclusion is correct.
> >
> > > > > The other interesting case would be resched_cpu(), which uses
> > > > > set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> > > > > atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> > > > > not set. If indeed not, it will send an IPI.
> > > > >
> > > > > This assumes the idle 'exit' path will do the same as the IPI does; and
> > > > > if you look at cpu_idle_loop() it does indeed do both
> > > > > preempt_fold_need_resched() and sched_ttwu_pending().
> > > > >
> > > > > Note that one cannot rely on irq_enter()/irq_exit() being called for the
> > > > > scheduler IPI.
> > > >
> > > > OK, thank you for the info! Any specific debug actions?
> > >
> > > Dunno, something like the below should bring visibility into the
> > > (lockless) wake_list thingy.
> > >
> > > So these trace_printk()s should happen between trace_sched_waking() and
> > > trace_sched_wakeup() (I've not fully read the thread, but ISTR you had
> > > some traces with these here thingies on).
> > >
> > > ---
> > > arch/x86/include/asm/bitops.h | 6 ++++--
> > > kernel/sched/core.c | 9 +++++++++
> > > 2 files changed, 13 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> > > index 7766d1cf096e..5345784d5e41 100644
> > > --- a/arch/x86/include/asm/bitops.h
> > > +++ b/arch/x86/include/asm/bitops.h
> > > @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> > > if (IS_IMMEDIATE(nr)) {
> > > asm volatile(LOCK_PREFIX "andb %1,%0"
> > > : CONST_MASK_ADDR(nr, addr)
> > > - : "iq" ((u8)~CONST_MASK(nr)));
> > > + : "iq" ((u8)~CONST_MASK(nr))
> > > + : "memory");
> > > } else {
> > > asm volatile(LOCK_PREFIX "btr %1,%0"
> > > : BITOP_ADDR(addr)
> > > - : "Ir" (nr));
> > > + : "Ir" (nr)
> > > + : "memory");
> > > }
> > > }
> >
> > Is the above addition of "memory" strictly for the debug below, or is
> > it also a potential fix?
> >
> > Starting it up regardless, but figured I should ask!
> >
> > Thanx, Paul
> >
> > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > > index 0b21e7a724e1..b446f73c530d 100644
> > > --- a/kernel/sched/core.c
> > > +++ b/kernel/sched/core.c
> > > @@ -1669,6 +1669,7 @@ void sched_ttwu_pending(void)
> > > while (llist) {
> > > p = llist_entry(llist, struct task_struct, wake_entry);
> > > llist = llist_next(llist);
> > > + trace_printk("waking %d\n", p->pid);
> > > ttwu_do_activate(rq, p, 0);
> > > }
> > >
> > > @@ -1719,6 +1720,7 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
> > > struct rq *rq = cpu_rq(cpu);
> > >
> > > if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
> > > + trace_printk("queued %d for waking on %d\n", p->pid, cpu);
> > > if (!set_nr_if_polling(rq->idle))
> > > smp_send_reschedule(cpu);
> > > else
> > > @@ -5397,10 +5399,17 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
> > > migrate_tasks(rq);
> > > BUG_ON(rq->nr_running != 1); /* the migration thread */
> > > raw_spin_unlock_irqrestore(&rq->lock, flags);
> > > +
> > > + /* really bad m'kay */
> > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > +
> > > break;
> > >
> > > case CPU_DEAD:
> > > calc_load_migrate(rq);
> > > +
> > > + /* more bad */
> > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > break;
> > > #endif
> > > }
> > >

2016-03-29 13:49:10

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Mon, Mar 28, 2016 at 05:28:14PM -0700, Paul E. McKenney wrote:
> On Mon, Mar 28, 2016 at 05:25:18PM -0700, Paul E. McKenney wrote:
> > On Mon, Mar 28, 2016 at 06:08:41AM -0700, Paul E. McKenney wrote:
> > > On Mon, Mar 28, 2016 at 08:25:47AM +0200, Peter Zijlstra wrote:
> > > > On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:
> >
> > [ . . . ]
> >
> > > > > OK, so I should instrument migration_call() if I get the repro rate up?
> > > >
> > > > Can do, maybe try the below first. (yes I know how long it all takes :/)
> > >
> > > OK, will run this today, then run calibration for last night's run this
> > > evening.

And of 18 two-hour runs, there were five failures, or about 28%.
That said, I don't have even one significant digit on the failure rate,
as 5 of 18 is within the 95% confidence limits for a failure probability
as low as 12.5% and as high as 47%.

However, the previous night's runs gave 7 failures in 24 two-hour runs,
for about a 29% failure rate. There is thus a good probability that my
disabling of TIF_POLLING_NRFLAG had no effect whatsoever, tantalizing
though that possibility might have been.

(FWIW, I use the pdf_binomial() and quantile_binomial() functions in
maxima for computing this stuff. Similar stuff is no doubt available
in other math/stat packages as well.)

So we have bugs, but not much idea where they are. Situation normal.

Other thoughts?

Thanx, Paul

> > And there was one failure out of ten runs. If last night's failure rate
> > was typical (7 of 24), then I believe we can be about 87% confident that
> > this change helped. That isn't all that confident, but...
>
> And, as Murphy would have it, the instrumentation didn't trigger. I just
> got the usual stall-warning messages with a starving RCU grace-period
> kthread.
>
> Thanx, Paul
>
> > Tested-by: Paul E. McKenney <[email protected]>
> >
> > So what to run tonight?
> >
> > The most sane approach would be to run stock in order to get a baseline
> > failure rate. It is tempting to run more of Peter's patch, but part of
> > the problem is that we don't know the current baseline.
> >
> > So baseline it is...
> >
> > Thanx, Paul
> >
> > > Speaking of which, last night's run (disabling TIF_POLLING_NRFLAG)
> > > consisted of 24 two-hour runs. Six of them had hard hangs, and another
> > > had a hang that eventually unhung of its own accord. I believe that this
> > > is significantly fewer failures than from a stock kernel, but I could
> > > be wrong, and it will take some serious testing to give statistical
> > > confidence for whatever conclusion is correct.
> > >
> > > > > > The other interesting case would be resched_cpu(), which uses
> > > > > > set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> > > > > > atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> > > > > > not set. If indeed not, it will send an IPI.
> > > > > >
> > > > > > This assumes the idle 'exit' path will do the same as the IPI does; and
> > > > > > if you look at cpu_idle_loop() it does indeed do both
> > > > > > preempt_fold_need_resched() and sched_ttwu_pending().
> > > > > >
> > > > > > Note that one cannot rely on irq_enter()/irq_exit() being called for the
> > > > > > scheduler IPI.
> > > > >
> > > > > OK, thank you for the info! Any specific debug actions?
> > > >
> > > > Dunno, something like the below should bring visibility into the
> > > > (lockless) wake_list thingy.
> > > >
> > > > So these trace_printk()s should happen between trace_sched_waking() and
> > > > trace_sched_wakeup() (I've not fully read the thread, but ISTR you had
> > > > some traces with these here thingies on).
> > > >
> > > > ---
> > > > arch/x86/include/asm/bitops.h | 6 ++++--
> > > > kernel/sched/core.c | 9 +++++++++
> > > > 2 files changed, 13 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> > > > index 7766d1cf096e..5345784d5e41 100644
> > > > --- a/arch/x86/include/asm/bitops.h
> > > > +++ b/arch/x86/include/asm/bitops.h
> > > > @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> > > > if (IS_IMMEDIATE(nr)) {
> > > > asm volatile(LOCK_PREFIX "andb %1,%0"
> > > > : CONST_MASK_ADDR(nr, addr)
> > > > - : "iq" ((u8)~CONST_MASK(nr)));
> > > > + : "iq" ((u8)~CONST_MASK(nr))
> > > > + : "memory");
> > > > } else {
> > > > asm volatile(LOCK_PREFIX "btr %1,%0"
> > > > : BITOP_ADDR(addr)
> > > > - : "Ir" (nr));
> > > > + : "Ir" (nr)
> > > > + : "memory");
> > > > }
> > > > }
> > >
> > > Is the above addition of "memory" strictly for the debug below, or is
> > > it also a potential fix?
> > >
> > > Starting it up regardless, but figured I should ask!
> > >
> > > Thanx, Paul
> > >
> > > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > > > index 0b21e7a724e1..b446f73c530d 100644
> > > > --- a/kernel/sched/core.c
> > > > +++ b/kernel/sched/core.c
> > > > @@ -1669,6 +1669,7 @@ void sched_ttwu_pending(void)
> > > > while (llist) {
> > > > p = llist_entry(llist, struct task_struct, wake_entry);
> > > > llist = llist_next(llist);
> > > > + trace_printk("waking %d\n", p->pid);
> > > > ttwu_do_activate(rq, p, 0);
> > > > }
> > > >
> > > > @@ -1719,6 +1720,7 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
> > > > struct rq *rq = cpu_rq(cpu);
> > > >
> > > > if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
> > > > + trace_printk("queued %d for waking on %d\n", p->pid, cpu);
> > > > if (!set_nr_if_polling(rq->idle))
> > > > smp_send_reschedule(cpu);
> > > > else
> > > > @@ -5397,10 +5399,17 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
> > > > migrate_tasks(rq);
> > > > BUG_ON(rq->nr_running != 1); /* the migration thread */
> > > > raw_spin_unlock_irqrestore(&rq->lock, flags);
> > > > +
> > > > + /* really bad m'kay */
> > > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > > +
> > > > break;
> > > >
> > > > case CPU_DEAD:
> > > > calc_load_migrate(rq);
> > > > +
> > > > + /* more bad */
> > > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > > break;
> > > > #endif
> > > > }
> > > >

2016-03-30 13:00:09

by Boqun Feng

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

Hi Paul,

On Mon, Mar 28, 2016 at 06:29:32AM -0700, Paul E. McKenney wrote:
> On Mon, Mar 28, 2016 at 08:28:51AM +0200, Peter Zijlstra wrote:
> > On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:
> >
> > > > Does that system have MONITOR/MWAIT errata?
> > >
> > > On the off-chance that this question was also directed at me,
> >
> > Hehe, it wasn't, however, since we're here..
> >
> > > here is
> > > what I am running on. I am running in a qemu/KVM virtual machine, in
> > > case that matters.
> >
> > Have you actually tried on real proper hardware? Does it still reproduce
> > there?
>
> Ross has, but I have not, given that I have a shared system on the one
> hand and a single-socket (four core, eight hardware thread) laptop on
> the other that has even longer reproduction times. The repeat-by is
> as follows:
>
> o Build a kernel with the following Kconfigs:
>
> CONFIG_SMP=y
> CONFIG_NR_CPUS=16
> CONFIG_PREEMPT_NONE=n
> CONFIG_PREEMPT_VOLUNTARY=n
> CONFIG_PREEMPT=y
> # This should result in CONFIG_PREEMPT_RCU=y
> CONFIG_HZ_PERIODIC=y
> CONFIG_NO_HZ_IDLE=n
> CONFIG_NO_HZ_FULL=n
> CONFIG_RCU_TRACE=y
> CONFIG_HOTPLUG_CPU=y
> CONFIG_RCU_FANOUT=2
> CONFIG_RCU_FANOUT_LEAF=2
> CONFIG_RCU_NOCB_CPU=n
> CONFIG_DEBUG_LOCK_ALLOC=n
> CONFIG_RCU_BOOST=y
> CONFIG_RCU_KTHREAD_PRIO=2
> CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
> CONFIG_RCU_EXPERT=y
> CONFIG_RCU_TORTURE_TEST=y
> CONFIG_PRINTK_TIME=y
> CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
> CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
> CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y
>
> If desired, you can instead build with CONFIG_RCU_TORTURE_TEST=m
> and modprobe/insmod the module manually.
>
> o Find a two-socket x86 system or larger, with at least 16 CPUs.
>
> o Boot the kernel with the following kernel boot parameters:
>
> rcutorture.onoff_interval=1 rcutorture.onoff_holdoff=30
>
> The onoff_holdoff is only needed for CONFIG_RCU_TORTURE_TEST=y.
> When manually setting up the module, you get the holdoff for
> free, courtesy of human timescales.
>

I ran several tests similar to this setup in a guest, the guest was
running in a 12-core Xeon X5690 host with kernel 4.4.5. The guest was
given 16 VCPUs and 2G memory.

Rather than RCU stall warnings, I was able to see a bug like this nearly
*everytime*:

[ 308.291635] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 308.292063] IP: [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
[ 308.292063] PGD 0
[ 308.292063] Oops: 0002 [#1] PREEMPT SMP
[ 308.292063] Modules linked in:
[ 308.292063] CPU: 11 PID: 798 Comm: torture_onoff Not tainted 4.5.0-rc1+ #14
[ 308.292063] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
[ 308.292063] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
[ 308.292063] RIP: 0010:[<ffffffff810b9452>] [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
[ 308.292063] RSP: 0018:ffff88007c6f7c98 EFLAGS: 00010086
[ 308.292063] RAX: dead000000000200 RBX: ffff88007fb6cc00 RCX: ffff88007fa2cc00
[ 308.292063] RDX: 0000000000000000 RSI: ffff88007fa2d6d0 RDI: ffff88007fb6cc00
[ 308.292063] RBP: ffff88007c6f7cc0 R08: 0000000000000000 R09: ffffffff81e4d360
[ 308.292063] R10: ffffea0001f2daa0 R11: 0000000000000000 R12: ffff88007fa2d6d0
[ 308.292063] R13: ffff88007fb6cc00 R14: 000000000000000b R15: ffff88007fa2c420
[ 308.292063] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
[ 308.292063] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 308.292063] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
[ 308.292063] Stack:
[ 308.292063] ffff88007fb6cc00 ffff88007fa2d6d8 ffff88007fa2dad0 ffff88007fa2d8d0
[ 308.292063] ffff88007fa2d4d8 ffff88007c6f7d08 ffffffff810b95c4 ffff88007fa2cc00
[ 308.292063] ffff88007fa2d648 00000000fffffff0 ffffffff81e4e0c0 0000000000000007
[ 308.292063] Call Trace:
[ 308.292063] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
[ 308.292063] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
[ 308.292063] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
[ 308.292063] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
[ 308.292063] [<ffffffff81057852>] _cpu_down+0x212/0x350
[ 308.292063] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
[ 308.292063] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
[ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
[ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
[ 308.292063] [<ffffffff810579bf>] cpu_down+0x2f/0x50
[ 308.292063] [<ffffffff811266b5>] torture_onoff+0x115/0x380
[ 308.292063] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
[ 308.292063] [<ffffffff810732f6>] kthread+0xd6/0xf0
[ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
[ 308.292063] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
[ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
[ 308.292063] Code: 56 41 55 41 54 53 48 8b 06 44 8b 77 40 48 85 c0 74 53 49 89 fd 49 89 f4 4d 8b 3c 24 66 66 66 66 90 49 8b 07 49 8b 57 08 48 85 c0 <48> 89 02 74 04 48 89 50 08 48 b8 00 02 00 00 00 00 ad de 4c 89
[ 308.292063] RIP [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
[ 308.292063] RSP <ffff88007c6f7c98>
[ 308.292063] CR2: 0000000000000000
[ 308.292063] ---[ end trace 29cb5d70ad875872 ]---


I'm not sure whether this is relevant, maybe this was caused by my
setup? But I attach two kernel logs and my config in case this could
help us solve the problem.

Another interesting I observed was that the time stamps of printk went
back in a while in some run, please note the log named "dmesg.1" in the
attachments.

A quick analysis of this bug is the null dereference happened at:

migrate_timer_list()
detach_timer();
__list_del();
WRITE_ONCE(*pprev, next); <- pprev is NULL

This seems highly unlikely, but as I said, I hit this almost every time
after a few minutes of starting rcutoture.

Any idea about whether this could be related to the RCU stall problem,
or this is another bug, or this actually happend by design for some
reasons?

Regards,
Boqun

> In the absence of instrumentation, I get failures usually within a
> couple of hours, though sometimes much longer. With instrumentation,
> the sky appears to be the limit. :-/
>
> Ross is running on bare metal with no CPU hotplug, so perhaps his setup
> is of more immediate interest. He is seeing the same symptoms that I am,
> namely a task being repeatedly awakened without actually coming out of
> TASK_INTERRUPTIBLE state, let alone running. As you pointed out earlier,
> he cannot be seeing the same bug that my crude patch suppresses, but
> given that I still see a few failures with that crude patch, it is quite
> possible that there is still a common bug.
>
> Thanx, Paul
>


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2016-03-30 13:30:48

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Wed, Mar 30, 2016 at 08:58:38PM +0800, Boqun Feng wrote:
> Hi Paul,
>
> On Mon, Mar 28, 2016 at 06:29:32AM -0700, Paul E. McKenney wrote:
> > On Mon, Mar 28, 2016 at 08:28:51AM +0200, Peter Zijlstra wrote:
> > > On Sun, Mar 27, 2016 at 02:09:14PM -0700, Paul E. McKenney wrote:
> > >
> > > > > Does that system have MONITOR/MWAIT errata?
> > > >
> > > > On the off-chance that this question was also directed at me,
> > >
> > > Hehe, it wasn't, however, since we're here..
> > >
> > > > here is
> > > > what I am running on. I am running in a qemu/KVM virtual machine, in
> > > > case that matters.
> > >
> > > Have you actually tried on real proper hardware? Does it still reproduce
> > > there?
> >
> > Ross has, but I have not, given that I have a shared system on the one
> > hand and a single-socket (four core, eight hardware thread) laptop on
> > the other that has even longer reproduction times. The repeat-by is
> > as follows:
> >
> > o Build a kernel with the following Kconfigs:
> >
> > CONFIG_SMP=y
> > CONFIG_NR_CPUS=16
> > CONFIG_PREEMPT_NONE=n
> > CONFIG_PREEMPT_VOLUNTARY=n
> > CONFIG_PREEMPT=y
> > # This should result in CONFIG_PREEMPT_RCU=y
> > CONFIG_HZ_PERIODIC=y
> > CONFIG_NO_HZ_IDLE=n
> > CONFIG_NO_HZ_FULL=n
> > CONFIG_RCU_TRACE=y
> > CONFIG_HOTPLUG_CPU=y
> > CONFIG_RCU_FANOUT=2
> > CONFIG_RCU_FANOUT_LEAF=2
> > CONFIG_RCU_NOCB_CPU=n
> > CONFIG_DEBUG_LOCK_ALLOC=n
> > CONFIG_RCU_BOOST=y
> > CONFIG_RCU_KTHREAD_PRIO=2
> > CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
> > CONFIG_RCU_EXPERT=y
> > CONFIG_RCU_TORTURE_TEST=y
> > CONFIG_PRINTK_TIME=y
> > CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
> > CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
> > CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y
> >
> > If desired, you can instead build with CONFIG_RCU_TORTURE_TEST=m
> > and modprobe/insmod the module manually.
> >
> > o Find a two-socket x86 system or larger, with at least 16 CPUs.
> >
> > o Boot the kernel with the following kernel boot parameters:
> >
> > rcutorture.onoff_interval=1 rcutorture.onoff_holdoff=30
> >
> > The onoff_holdoff is only needed for CONFIG_RCU_TORTURE_TEST=y.
> > When manually setting up the module, you get the holdoff for
> > free, courtesy of human timescales.
> >
>
> I ran several tests similar to this setup in a guest, the guest was
> running in a 12-core Xeon X5690 host with kernel 4.4.5. The guest was
> given 16 VCPUs and 2G memory.
>
> Rather than RCU stall warnings, I was able to see a bug like this nearly
> *everytime*:
>
> [ 308.291635] BUG: unable to handle kernel NULL pointer dereference at (null)
> [ 308.292063] IP: [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0

New one on me!

> [ 308.292063] PGD 0
> [ 308.292063] Oops: 0002 [#1] PREEMPT SMP
> [ 308.292063] Modules linked in:
> [ 308.292063] CPU: 11 PID: 798 Comm: torture_onoff Not tainted 4.5.0-rc1+ #14
> [ 308.292063] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 308.292063] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
> [ 308.292063] RIP: 0010:[<ffffffff810b9452>] [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 308.292063] RSP: 0018:ffff88007c6f7c98 EFLAGS: 00010086
> [ 308.292063] RAX: dead000000000200 RBX: ffff88007fb6cc00 RCX: ffff88007fa2cc00
> [ 308.292063] RDX: 0000000000000000 RSI: ffff88007fa2d6d0 RDI: ffff88007fb6cc00
> [ 308.292063] RBP: ffff88007c6f7cc0 R08: 0000000000000000 R09: ffffffff81e4d360
> [ 308.292063] R10: ffffea0001f2daa0 R11: 0000000000000000 R12: ffff88007fa2d6d0
> [ 308.292063] R13: ffff88007fb6cc00 R14: 000000000000000b R15: ffff88007fa2c420
> [ 308.292063] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 308.292063] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 308.292063] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 308.292063] Stack:
> [ 308.292063] ffff88007fb6cc00 ffff88007fa2d6d8 ffff88007fa2dad0 ffff88007fa2d8d0
> [ 308.292063] ffff88007fa2d4d8 ffff88007c6f7d08 ffffffff810b95c4 ffff88007fa2cc00
> [ 308.292063] ffff88007fa2d648 00000000fffffff0 ffffffff81e4e0c0 0000000000000007
> [ 308.292063] Call Trace:
> [ 308.292063] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 308.292063] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 308.292063] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 308.292063] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 308.292063] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 308.292063] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 308.292063] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 308.292063] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 308.292063] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 308.292063] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 308.292063] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 308.292063] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 308.292063] Code: 56 41 55 41 54 53 48 8b 06 44 8b 77 40 48 85 c0 74 53 49 89 fd 49 89 f4 4d 8b 3c 24 66 66 66 66 90 49 8b 07 49 8b 57 08 48 85 c0 <48> 89 02 74 04 48 89 50 08 48 b8 00 02 00 00 00 00 ad de 4c 89
> [ 308.292063] RIP [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 308.292063] RSP <ffff88007c6f7c98>
> [ 308.292063] CR2: 0000000000000000
> [ 308.292063] ---[ end trace 29cb5d70ad875872 ]---
>
>
> I'm not sure whether this is relevant, maybe this was caused by my
> setup? But I attach two kernel logs and my config in case this could
> help us solve the problem.
>
> Another interesting I observed was that the time stamps of printk went
> back in a while in some run, please note the log named "dmesg.1" in the
> attachments.

That can cause all sorts of problems, including RCU CPU stall warnings.

So I see the following in dmesg.1, courtesy of:

sed -e 's/].*$//' < /tmp/dmesg.1 | awk '{ if (oldtime != "" && oldtime > $2) print; oldtime = $2 }'

1.128644 -> 1.128642: Only two microseconds backwards, so not enough
to cause a stall warning (need about 21 seconds for that).
1.143582 -> 1.143575: Seven microseconds backwards.
316.386056 -> 421.191446: 104.8 seconds backwards, plenty to cause
all sorts of problems, including stall warnings.
311.122004 -> 316.338053: 5.2 seconds backwards, can cause all sorts
of problems, but not likely stall warnings.

> A quick analysis of this bug is the null dereference happened at:
>
> migrate_timer_list()
> detach_timer();
> __list_del();
> WRITE_ONCE(*pprev, next); <- pprev is NULL
>
> This seems highly unlikely, but as I said, I hit this almost every time
> after a few minutes of starting rcutoture.

Looks like a malformed list, which does look quite ugly. No idea
whether or not this could be related to backwards-going time, but
fixing the backwards-going time is a good first step.

> Any idea about whether this could be related to the RCU stall problem,
> or this is another bug, or this actually happend by design for some
> reasons?

One of your backwards-time incidents could cause both the RCU CPU stall
warnings and also the soft lockup I see there.

If this is an older system, it might have an unreliable TSC. If the
kernel is nevertheless using TSC, this sort of thing could happen.
The usual advice is to boot using HPET, but perhaps others on the
list have more specific advice.

Thanx, Paul

> Regards,
> Boqun
>
> > In the absence of instrumentation, I get failures usually within a
> > couple of hours, though sometimes much longer. With instrumentation,
> > the sky appears to be the limit. :-/
> >
> > Ross is running on bare metal with no CPU hotplug, so perhaps his setup
> > is of more immediate interest. He is seeing the same symptoms that I am,
> > namely a task being repeatedly awakened without actually coming out of
> > TASK_INTERRUPTIBLE state, let alone running. As you pointed out earlier,
> > he cannot be seeing the same bug that my crude patch suppresses, but
> > given that I still see a few failures with that crude patch, it is quite
> > possible that there is still a common bug.
> >
> > Thanx, Paul
> >

> [ 0.000000] Linux version 4.5.0-rc1+ (root@insomnia) (gcc version 5.3.0 (GCC) ) #14 SMP PREEMPT Wed Mar 30 20:01:04 CST 2016
> [ 0.000000] Command line: noapic selinux=0 console=ttyS0 rcutorture.onoff_interval=1 rcutorture.onff_holdoff=30
> [ 0.000000] x86/fpu: Legacy x87 FPU detected.
> [ 0.000000] x86/fpu: Using 'lazy' FPU context switches.
> [ 0.000000] e820: BIOS-provided physical RAM map:
> [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
> [ 0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000007ffdefff] usable
> [ 0.000000] BIOS-e820: [mem 0x000000007ffdf000-0x000000007fffffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
> [ 0.000000] NX (Execute Disable) protection: active
> [ 0.000000] SMBIOS 2.8 present.
> [ 0.000000] e820: last_pfn = 0x7ffdf max_arch_pfn = 0x400000000
> [ 0.000000] x86/PAT: Configuration [0-7]: WB WC UC- UC WB WC UC- WT
> [ 0.000000] found SMP MP-table at [mem 0x000f6a50-0x000f6a5f] mapped at [ffff8800000f6a50]
> [ 0.000000] Scanning 1 areas for low memory corruption
> [ 0.000000] Using GB pages for direct mapping
> [ 0.000000] RAMDISK: [mem 0x7fcd4000-0x7ffcffff]
> [ 0.000000] ACPI: Early table checksum verification disabled
> [ 0.000000] ACPI: RSDP 0x00000000000F6A00 000014 (v00 BOCHS )
> [ 0.000000] ACPI: RSDT 0x000000007FFE1580 000034 (v01 BOCHS BXPCRSDT 00000001 BXPC 00000001)
> [ 0.000000] ACPI: FACP 0x000000007FFE061A 000074 (v01 BOCHS BXPCFACP 00000001 BXPC 00000001)
> [ 0.000000] ACPI: DSDT 0x000000007FFDFA80 000B9A (v01 BOCHS BXPCDSDT 00000001 BXPC 00000001)
> [ 0.000000] ACPI: FACS 0x000000007FFDFA40 000040
> [ 0.000000] ACPI: SSDT 0x000000007FFE068E 000DCA (v01 BOCHS BXPCSSDT 00000001 BXPC 00000001)
> [ 0.000000] ACPI: APIC 0x000000007FFE1458 0000F0 (v01 BOCHS BXPCAPIC 00000001 BXPC 00000001)
> [ 0.000000] ACPI: HPET 0x000000007FFE1548 000038 (v01 BOCHS BXPCHPET 00000001 BXPC 00000001)
> [ 0.000000] No NUMA configuration found
> [ 0.000000] Faking a node at [mem 0x0000000000000000-0x000000007ffdefff]
> [ 0.000000] NODE_DATA(0) allocated [mem 0x7ffdb000-0x7ffdefff]
> [ 0.000000] Zone ranges:
> [ 0.000000] DMA [mem 0x0000000000001000-0x0000000000ffffff]
> [ 0.000000] DMA32 [mem 0x0000000001000000-0x000000007ffdefff]
> [ 0.000000] Normal empty
> [ 0.000000] Movable zone start for each node
> [ 0.000000] Early memory node ranges
> [ 0.000000] node 0: [mem 0x0000000000001000-0x000000000009efff]
> [ 0.000000] node 0: [mem 0x0000000000100000-0x000000007ffdefff]
> [ 0.000000] Initmem setup node 0 [mem 0x0000000000001000-0x000000007ffdefff]
> [ 0.000000] ACPI: PM-Timer IO Port: 0x608
> [ 0.000000] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1])
> [ 0.000000] ACPI: Skipping IOAPIC probe due to 'noapic' option.
> [ 0.000000] Using ACPI for processor (LAPIC) configuration information
> [ 0.000000] ACPI: HPET id: 0x8086a201 base: 0xfed00000
> [ 0.000000] Intel MultiProcessor Specification v1.4
> [ 0.000000] MPTABLE: OEM ID: BOCHSCPU
> [ 0.000000] MPTABLE: Product ID: 0.1
> [ 0.000000] MPTABLE: APIC at: 0xFEE00000
> [ 0.000000] IOAPIC[0]: apic_id 0, version 17, address 0xfec00000, GSI 0-23
> [ 0.000000] Processors: 16
> [ 0.000000] smpboot: Allowing 16 CPUs, 0 hotplug CPUs
> [ 0.000000] PM: Registered nosave memory: [mem 0x00000000-0x00000fff]
> [ 0.000000] PM: Registered nosave memory: [mem 0x0009f000-0x0009ffff]
> [ 0.000000] PM: Registered nosave memory: [mem 0x000a0000-0x000effff]
> [ 0.000000] PM: Registered nosave memory: [mem 0x000f0000-0x000fffff]
> [ 0.000000] e820: [mem 0x80000000-0xfeffbfff] available for PCI devices
> [ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1910969940391419 ns
> [ 0.000000] setup_percpu: NR_CPUS:16 nr_cpumask_bits:16 nr_cpu_ids:16 nr_node_ids:1
> [ 0.000000] PERCPU: Embedded 32 pages/cpu @ffff88007fa00000 s92008 r8192 d30872 u131072
> [ 0.000000] Built 1 zonelists in Node order, mobility grouping on. Total pages: 515944
> [ 0.000000] Policy zone: DMA32
> [ 0.000000] Kernel command line: noapic selinux=0 console=ttyS0 rcutorture.onoff_interval=1 rcutorture.onff_holdoff=30
> [ 0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes)
> [ 0.000000] Memory: 2040780K/2096628K available (8931K kernel code, 1258K rwdata, 3700K rodata, 1092K init, 984K bss, 55848K reserved, 0K cma-reserved)
> [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=16, Nodes=1
> [ 0.000000] Preemptible hierarchical RCU implementation.
> [ 0.000000] RCU debugfs-based tracing is enabled.
> [ 0.000000] CONFIG_RCU_FANOUT set to non-default value of 2
> [ 0.000000] RCU torture testing starts during boot.
> [ 0.000000] Four(or more)-level hierarchy is enabled.
> [ 0.000000] Build-time adjustment of leaf fanout to 2.
> [ 0.000000] RCU kthread priority: 2.
> [ 0.000000] NR_IRQS:4352 nr_irqs:552 16
> [ 0.000000] Console: colour *CGA 80x25
> [ 0.000000] console [ttyS0] enabled
> [ 0.000000] clocksource: hpet: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604467 ns
> [ 0.000000] tsc: Fast TSC calibration using PIT
> [ 0.000000] tsc: Detected 3466.555 MHz processor
> [ 0.002013] Calibrating delay loop (skipped), value calculated using timer frequency.. 6933.11 BogoMIPS (lpj=3466555)
> [ 0.003221] pid_max: default: 32768 minimum: 301
> [ 0.004006] ACPI: Core revision 20160108
> [ 0.005400] ACPI: 2 ACPI AML tables successfully acquired and loaded
> [ 0.005895]
> [ 0.006006] ACPI: setting ELCR to 0200 (from 0c00)
> [ 0.006390] Security Framework initialized
> [ 0.006710] SELinux: Disabled at boot.
> [ 0.007098] Dentry cache hash table entries: 262144 (order: 9, 2097152 bytes)
> [ 0.008111] Inode-cache hash table entries: 131072 (order: 8, 1048576 bytes)
> [ 0.008795] Mount-cache hash table entries: 4096 (order: 3, 32768 bytes)
> [ 0.009005] Mountpoint-cache hash table entries: 4096 (order: 3, 32768 bytes)
> [ 0.010313] mce: CPU supports 10 MCE banks
> [ 0.010663] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0
> [ 0.011003] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0
> [ 0.012726] Freeing SMP alternatives memory: 32K (ffffffff8204d000 - ffffffff82055000)
> [ 0.013357] Switched APIC routing to physical flat.
> [ 0.014080] smpboot: CPU0: Intel(R) Xeon(R) CPU X5690 @ 3.47GHz (family: 0x6, model: 0x2c, stepping: 0x2)
> [ 0.014920] Performance Events: 16-deep LBR, Westmere events, Intel PMU driver.
> [ 0.015429] perf_event_intel: CPUID marked event: 'bus cycles' unavailable
> [ 0.015949] ... version: 2
> [ 0.016003] ... bit width: 48
> [ 0.016329] ... generic registers: 4
> [ 0.016636] ... value mask: 0000ffffffffffff
> [ 0.017003] ... max period: 000000007fffffff
> [ 0.017404] ... fixed-purpose events: 3
> [ 0.017710] ... event mask: 000000070000000f
> [ 0.027039] x86: Booting SMP configuration:
> [ 0.027433] .... node #0, CPUs: #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15
> [ 0.985023] x86: Booted up 1 node, 16 CPUs
> [ 0.985362] smpboot: Total of 16 processors activated (111447.03 BogoMIPS)
> [ 0.987547] devtmpfs: initialized
> [ 0.988368] kworker/u32:0 (98) used greatest stack depth: 13928 bytes left
> [ 0.988536] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1911260446275000 ns
> [ 0.988993] RTC time: 12:03:37, date: 03/30/16
> [ 0.989101] NET: Registered protocol family 16
> [ 0.989570] kworker/u32:1 (100) used greatest stack depth: 13736 bytes left
> [ 0.996022] cpuidle: using governor menu
> [ 0.996672] ACPI: bus type PCI registered
> [ 0.997125] PCI: Using configuration type 1 for base access
> [ 1.010381] HugeTLB registered 2 MB page size, pre-allocated 0 pages
> [ 1.011926] ACPI: Added _OSI(Module Device)
> [ 1.012004] ACPI: Added _OSI(Processor Device)
> [ 1.012349] ACPI: Added _OSI(3.0 _SCP Extensions)
> [ 1.012717] ACPI: Added _OSI(Processor Aggregator Device)
> [ 1.014251] ACPI: Interpreter enabled
> [ 1.014628] ACPI: (supports S0 S3 S4 S5)
> [ 1.014997] ACPI: Using PIC for interrupt routing
> [ 1.015037] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug
> [ 1.019866] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])
> [ 1.020013] acpi PNP0A03:00: _OSC: OS supports [ASPM ClockPM Segments MSI]
> [ 1.020677] acpi PNP0A03:00: _OSC failed (AE_NOT_FOUND); disabling ASPM
> [ 1.021011] acpi PNP0A03:00: fail to add MMCONFIG information, can't access extended PCI configuration space under this bridge.
> [ 1.022058] PCI host bridge to bus 0000:00
> [ 1.022466] pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window]
> [ 1.023011] pci_bus 0000:00: root bus resource [io 0x0d00-0xffff window]
> [ 1.023551] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff window]
> [ 1.024004] pci_bus 0000:00: root bus resource [mem 0x80000000-0xfebfffff window]
> [ 1.024578] pci_bus 0000:00: root bus resource [bus 00-ff]
> [ 1.028247] pci 0000:00:01.1: legacy IDE quirk: reg 0x10: [io 0x01f0-0x01f7]
> [ 1.028778] pci 0000:00:01.1: legacy IDE quirk: reg 0x14: [io 0x03f6]
> [ 1.029004] pci 0000:00:01.1: legacy IDE quirk: reg 0x18: [io 0x0170-0x0177]
> [ 1.029537] pci 0000:00:01.1: legacy IDE quirk: reg 0x1c: [io 0x0376]
> [ 1.030369] pci 0000:00:01.3: quirk: [io 0x0600-0x063f] claimed by PIIX4 ACPI
> [ 1.030936] pci 0000:00:01.3: quirk: [io 0x0700-0x070f] claimed by PIIX4 SMB
> [ 1.037175] ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11)
> [ 1.037744] ACPI: PCI Interrupt Link [LNKB] (IRQs 5 *10 11)
> [ 1.038196] ACPI: PCI Interrupt Link [LNKC] (IRQs 5 10 *11)
> [ 1.038745] ACPI: PCI Interrupt Link [LNKD] (IRQs 5 10 *11)
> [ 1.039172] ACPI: PCI Interrupt Link [LNKS] (IRQs *9)
> [ 1.040561] ACPI: Enabled 16 GPEs in block 00 to 0F
> [ 1.041109] vgaarb: loaded
> [ 1.041419] SCSI subsystem initialized
> [ 1.041953] ACPI: bus type USB registered
> [ 1.042040] usbcore: registered new interface driver usbfs
> [ 1.042487] usbcore: registered new interface driver hub
> [ 1.043100] usbcore: registered new device driver usb
> [ 1.043539] pps_core: LinuxPPS API ver. 1 registered
> [ 1.043979] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <[email protected]>
> [ 1.044019] PTP clock support registered
> [ 1.044684] Advanced Linux Sound Architecture Driver Initialized.
> [ 1.045053] PCI: Using ACPI for IRQ routing
> [ 1.045729] NetLabel: Initializing
> [ 1.046004] NetLabel: domain hash size = 128
> [ 1.046365] NetLabel: protocols = UNLABELED CIPSOv4
> [ 1.046767] NetLabel: unlabeled traffic allowed by default
> [ 1.047180] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0
> [ 1.047609] hpet0: 3 comparators, 64-bit 100.000000 MHz counter
> [ 1.052714] clocksource: Switched to clocksource hpet
> [ 1.059250] VFS: Disk quotas dquot_6.6.0
> [ 1.059578] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
> [ 1.060306] pnp: PnP ACPI init
> [ 1.060970] pnp: PnP ACPI: found 5 devices
> [ 1.069312] clocksource: acpi_pm: mask: 0xffffff max_cycles: 0xffffff, max_idle_ns: 2085701024 ns
> [ 1.070069] NET: Registered protocol family 2
> [ 1.070632] TCP established hash table entries: 16384 (order: 5, 131072 bytes)
> [ 1.071401] TCP bind hash table entries: 16384 (order: 7, 524288 bytes)
> [ 1.072064] TCP: Hash tables configured (established 16384 bind 16384)
> [ 1.072688] UDP hash table entries: 1024 (order: 4, 98304 bytes)
> [ 1.073276] UDP-Lite hash table entries: 1024 (order: 4, 98304 bytes)
> [ 1.073827] NET: Registered protocol family 1
> [ 1.074495] RPC: Registered named UNIX socket transport module.
> [ 1.074955] RPC: Registered udp transport module.
> [ 1.075464] RPC: Registered tcp transport module.
> [ 1.075826] RPC: Registered tcp NFSv4.1 backchannel transport module.
> [ 1.076439] pci 0000:00:00.0: Limiting direct PCI/PCI transfers
> [ 1.076891] pci 0000:00:01.0: PIIX3: Enabling Passive Release
> [ 1.077443] pci 0000:00:01.0: Activating ISA DMA hang workarounds
> [ 1.077963] Unpacking initramfs...
> [ 1.120173] Freeing initrd memory: 3056K (ffff88007fcd4000 - ffff88007ffd0000)
> [ 1.122503] Scanning for low memory corruption every 60 seconds
> [ 1.123167] rcu-torture:--- Start of test: nreaders=15 nfakewriters=4 stat_interval=60 verbose=1 test_no_idle_hz=1 shuffle_interval=3 stutter=5 irqreader=1 fqs_duration=0 fqs_holdoff=0 fqs_stutter=3 test_boost=1/0 test_boost_interval=7 test_boost_duration=4 shutdown_secs=0 stall_cpu=0 stall_cpu_holdoff=10 n_barrier_cbs=0 onoff_interval=1 onoff_holdoff=0
> [ 1.125747] rcu-torture: Creating rcu_torture_writer task
> [ 1.126429] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.126429] rcu-torture: rcu_torture_writer task started
> [ 1.126430] rcu-torture: Grace periods expedited from boot/sysfs for rcu,
> [ 1.126430] rcu-torture: Testing of dynamic grace-period expediting diabled.
> [ 1.128644] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.128642] rcu-torture: rcu_torture_fakewriter task started
> [ 1.129727] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.129733] rcu-torture: rcu_torture_fakewriter task started
> [ 1.130898] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.130906] rcu-torture: rcu_torture_fakewriter task started
> [ 1.132691] rcu-torture: Creating rcu_torture_reader task
> [ 1.132694] rcu-torture: rcu_torture_fakewriter task started
> [ 1.133744] rcu-torture: Creating rcu_torture_reader task
> [ 1.133750] rcu-torture: rcu_torture_reader task started
> [ 1.135313] rcu-torture: Creating rcu_torture_reader task
> [ 1.135317] rcu-torture: rcu_torture_reader task started
> [ 1.136682] rcu-torture: Creating rcu_torture_reader task
> [ 1.136686] rcu-torture: rcu_torture_reader task started
> [ 1.138108] rcu-torture: Creating rcu_torture_reader task
> [ 1.138809] rcu-torture: Creating rcu_torture_reader task
> [ 1.138818] rcu-torture: rcu_torture_reader task started
> [ 1.140081] rcu-torture: rcu_torture_reader task started
> [ 1.140856] rcu-torture: Creating rcu_torture_reader task
> [ 1.140866] rcu-torture: rcu_torture_reader task started
> [ 1.142268] rcu-torture: Creating rcu_torture_reader task
> [ 1.142271] rcu-torture: rcu_torture_reader task started
> [ 1.143582] rcu-torture: Creating rcu_torture_reader task
> [ 1.143575] rcu-torture: rcu_torture_reader task started
> [ 1.144936] rcu-torture: Creating rcu_torture_reader task
> [ 1.144938] rcu-torture: rcu_torture_reader task started
> [ 1.147747] rcu-torture: Creating rcu_torture_reader task
> [ 1.148083] rcu-torture: rcu_torture_reader task started
> [ 1.150115] rcu-torture: Creating rcu_torture_reader task
> [ 1.150770] rcu-torture: Creating rcu_torture_reader task
> [ 1.150778] rcu-torture: rcu_torture_reader task started
> [ 1.151081] rcu-torture: rcu_torture_reader task started
> [ 1.152751] rcu-torture: Creating rcu_torture_reader task
> [ 1.152757] rcu-torture: rcu_torture_reader task started
> [ 1.154181] rcu-torture: Creating rcu_torture_reader task
> [ 1.154185] rcu-torture: rcu_torture_reader task started
> [ 1.155491] rcu-torture: Creating rcu_torture_stats task
> [ 1.156175] rcu-torture: rcu_torture_reader task started
> [ 1.158111] rcu-torture: Creating torture_shuffle task
> [ 1.158225] rcu-torture: rcu_torture_stats task started
> [ 1.160088] rcu-torture: Creating torture_stutter task
> [ 1.162072] rcu-torture: torture_shuffle task started
> [ 1.162089] rcu-torture: Creating torture_onoff task
> [ 1.162096] rcu-torture: torture_stutter task started
> [ 1.163132] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.163136] rcu-torture: torture_onoff task started
> [ 1.163137] rcu-torture:torture_onoff task: offlining 1
> [ 1.165109] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.165188] rcu-torture: rcu_torture_cbflood task started
> [ 1.166119] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.166175] rcu-torture: rcu_torture_cbflood task started
> [ 1.167091] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.167186] rcu-torture: rcu_torture_cbflood task started
> [ 1.168161] rcu-torture: rcu_torture_cbflood task started
> [ 1.198566] Cannot set affinity for irq 0
> [ 1.201317] rcu-torture:torture_onoff task: offlined 1
> [ 1.202330] futex hash table entries: 4096 (order: 6, 262144 bytes)
> [ 1.203196] audit: initializing netlink subsys (disabled)
> [ 1.203818] audit: type=2000 audit(1459339417.203:1): initialized
> [ 1.214213] NFS: Registering the id_resolver key type
> [ 1.214798] Key type id_resolver registered
> [ 1.216354] Key type id_legacy registered
> [ 1.244465] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 251)
> [ 1.245389] io scheduler noop registered
> [ 1.245828] io scheduler deadline registered
> [ 1.246386] io scheduler cfq registered (default)
> [ 1.246974] pci_hotplug: PCI Hot Plug PCI Core version: 0.5
> [ 1.247793] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0
> [ 1.248696] ACPI: Power Button [PWRF]
> [ 1.250818] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> [ 1.298067] 00:04: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
> [ 1.301459] Non-volatile memory driver v1.3
> [ 1.301993] Linux agpgart interface v0.103
> [ 1.302664] [drm] Initialized drm 1.1.0 20060810
> [ 1.333318] loop: module loaded
> [ 1.338108] scsi host0: ata_piix
> [ 1.344082] scsi host1: ata_piix
> [ 1.344504] ata1: PATA max MWDMA2 cmd 0x1f0 ctl 0x3f6 bmdma 0xc040 irq 14
> [ 1.345328] ata2: PATA max MWDMA2 cmd 0x170 ctl 0x376 bmdma 0xc048 irq 15
> [ 1.346267] e100: Intel(R) PRO/100 Network Driver, 3.5.24-k2-NAPI
> [ 1.346946] e100: Copyright(c) 1999-2006 Intel Corporation
> [ 1.347667] e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI
> [ 1.348576] e1000: Copyright (c) 1999-2006 Intel Corporation.
> [ 1.401454] ACPI: PCI Interrupt Link [LNKB] enabled at IRQ 10
> [ 1.837131] e1000 0000:00:02.0 eth0: (PCI:33MHz:32-bit) 52:54:00:12:34:56
> [ 1.837856] e1000 0000:00:02.0 eth0: Intel(R) PRO/1000 Network Connection
> [ 1.839514] sky2: driver version 1.30
> [ 1.842083] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
> [ 1.842792] ehci-pci: EHCI PCI platform driver
> [ 1.843372] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
> [ 1.844095] ohci-pci: OHCI PCI platform driver
> [ 1.844586] uhci_hcd: USB Universal Host Controller Interface driver
> [ 1.848330] usbcore: registered new interface driver usblp
> [ 1.848944] usbcore: registered new interface driver usb-storage
> [ 1.850748] i8042: PNP: PS/2 Controller [PNP0303:KBD,PNP0f13:MOU] at 0x60,0x64 irq 1,12
> [ 1.853219] serio: i8042 KBD port at 0x60,0x64 irq 1
> [ 1.853811] serio: i8042 AUX port at 0x60,0x64 irq 12
> [ 1.854564] mousedev: PS/2 mouse device common for all mice
> [ 1.855778] input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input1
> [ 1.856946] rtc_cmos 00:00: RTC can wake from S4
> [ 1.857843] rtc_cmos 00:00: rtc core: registered rtc_cmos as rtc0
> [ 1.860852] rtc_cmos 00:00: alarms up to one day, 114 bytes nvram, hpet irqs
> [ 1.861917] device-mapper: ioctl: 4.34.0-ioctl (2015-10-28) initialised: [email protected]
> [ 1.863983] hidraw: raw HID events driver (C) Jiri Kosina
> [ 1.864831] usbcore: registered new interface driver usbhid
> [ 1.866528] usbhid: USB HID core driver
> [ 1.868362] Netfilter messages via NETLINK v0.30.
> [ 1.868937] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
> [ 1.869776] ctnetlink v0.93: registering with nfnetlink.
> [ 1.938103] ip_tables: (C) 2000-2006 Netfilter Core Team
> [ 1.954088] Initializing XFRM netlink socket
> [ 1.954745] NET: Registered protocol family 10
> [ 1.959227] ip6_tables: (C) 2000-2006 Netfilter Core Team
> [ 2.045095] sit: IPv6 over IPv4 tunneling driver
> [ 2.045761] NET: Registered protocol family 17
> [ 2.046381] Key type dns_resolver registered
> [ 2.048272] microcode: CPU0 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.054101] microcode: CPU2 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.054727] microcode: CPU3 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.055398] microcode: CPU4 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.057091] microcode: CPU5 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.058077] microcode: CPU6 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.059488] microcode: CPU7 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.060165] microcode: CPU8 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.060792] microcode: CPU9 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.062457] microcode: CPU10 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.063193] microcode: CPU11 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.063807] microcode: CPU12 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.065476] microcode: CPU13 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.066140] microcode: CPU14 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.066776] microcode: CPU15 sig=0x206c2, pf=0x1, revision=0x1
> [ 2.069136] microcode: Microcode Update Driver: v2.01 <[email protected]>, Peter Oruba
> [ 2.073334] registered taskstats version 1
> [ 2.120085] tsc: Refined TSC clocksource calibration: 3466.787 MHz
> [ 2.120116] Magic number: 8:22:78
> [ 2.121287] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x31f8c1a78ae, max_idle_ns: 440795301702 ns
> [ 2.122453] console [netcon0] enabled
> [ 2.122838] netconsole: network logging started
> [ 2.123496] ALSA device list:
> [ 2.123826] No soundcards found.
> [ 2.132882] Freeing unused kernel memory: 1092K (ffffffff81f3c000 - ffffffff8204d000)
> [ 2.133781] Write protecting the kernel read-only data: 14336k
> [ 2.142268] Freeing unused kernel memory: 1296K (ffff8800018bc000 - ffff880001a00000)
> [ 2.147172] Freeing unused kernel memory: 396K (ffff880001d9d000 - ffff880001e00000)
> :: running early hook [udev]
> Warning: /lib/modules/4.5.0-rc1+/modules.devname not found - ignoring
> [ 2.156227] random: systemd-tmpfile urandom read with 3 bits of entropy available
> starting version 228
> :: running hook [udev]
> :: Triggering uevents...
> [ 2.203265] rcu-torture:torture_onoff task: offlining 13
> [ 2.311090] smpboot: CPU 13 is now offline
> [ 2.335175] rcu-torture:torture_onoff task: offlined 13
> [ 2.374076] hrtimer: interrupt took 3052040 ns
> ERROR: device '' not found. Skipping fsck.
> ERROR: Unable to find root device ''.
> You are being dropped to a recovery shell
> Type 'exit' to try and continue booting
> sh: can't access tty; job control turned off
> [rootfs /]# [ 2.532402] input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input3
> [ 3.175686] clocksource: Switched to clocksource tsc
> [ 3.335015] rcu-torture:torture_onoff task: offlining 9
> [ 3.458326] smpboot: CPU 9 is now offline
> [ 3.473041] rcu-torture:torture_onoff task: offlined 9
> [ 4.474012] rcu-torture:torture_onoff task: offlining 3
> [ 4.658671] smpboot: CPU 3 is now offline
> [ 4.707907] rcu-torture:torture_onoff task: offlined 3
> [ 5.708012] rcu-torture:torture_onoff task: onlining 13
> [ 5.718635] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 5.849194] rcu-torture:torture_onoff task: onlined 13
> [ 6.849043] rcu-torture:torture_onoff task: offlining 6
> [ 6.918255] smpboot: CPU 6 is now offline
> [ 6.973968] rcu-torture:torture_onoff task: offlined 6
> [ 7.975013] rcu-torture:torture_onoff task: offlining 13
> [ 8.030256] smpboot: CPU 13 is now offline
> [ 8.084823] rcu-torture:torture_onoff task: offlined 13
> [ 9.085014] rcu-torture:torture_onoff task: offlining 2
> [ 9.141234] smpboot: CPU 2 is now offline
> [ 9.195554] rcu-torture:torture_onoff task: offlined 2
> [ 10.195008] rcu-torture:torture_onoff task: onlining 6
> [ 10.249497] smpboot: Booting Node 0 Processor 6 APIC 0x6
> [ 10.275147] rcu-torture:torture_onoff task: onlined 6
> [ 11.275012] rcu-torture:torture_onoff task: offlining 8
> [ 11.348220] smpboot: CPU 8 is now offline
> [ 11.352839] rcu-torture:torture_onoff task: offlined 8
> [ 12.353015] rcu-torture:torture_onoff task: onlining 8
> [ 12.376796] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 12.523163] rcu-torture:torture_onoff task: onlined 8
> [ 13.523013] rcu-torture:torture_onoff task: offlining 6
> [ 13.571220] smpboot: CPU 6 is now offline
> [ 13.577564] rcu-torture:torture_onoff task: offlined 6
> [ 14.578012] rcu-torture:torture_onoff task: onlining 1
> [ 14.602743] x86: Booting SMP configuration:
> [ 14.603246] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 14.729178] microcode: CPU1 sig=0x206c2, pf=0x1, revision=0x1
> [ 14.729828] rcu-torture:torture_onoff task: onlined 1
> [ 15.730012] rcu-torture:torture_onoff task: onlining 9
> [ 15.764765] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 15.918505] rcu-torture:torture_onoff task: onlined 9
> [ 16.919012] rcu-torture:torture_onoff task: offlining 15
> [ 17.032826] smpboot: CPU 15 is now offline
> [ 17.088898] rcu-torture:torture_onoff task: offlined 15
> [ 18.089019] rcu-torture:torture_onoff task: offlining 1
> [ 18.144244] smpboot: CPU 1 is now offline
> [ 18.198796] rcu-torture:torture_onoff task: offlined 1
> [ 19.199020] rcu-torture:torture_onoff task: onlining 1
> [ 19.253718] x86: Booting SMP configuration:
> [ 19.254220] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 19.280164] rcu-torture:torture_onoff task: onlined 1
> [ 20.280009] rcu-torture:torture_onoff task: onlining 13
> [ 20.334516] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 20.360165] rcu-torture:torture_onoff task: onlined 13
> [ 21.360012] rcu-torture:torture_onoff task: offlining 5
> [ 21.398318] smpboot: CPU 5 is now offline
> [ 21.402867] rcu-torture:torture_onoff task: offlined 5
> [ 22.403014] rcu-torture:torture_onoff task: offlining 9
> [ 22.414258] smpboot: CPU 9 is now offline
> [ 22.460826] rcu-torture:torture_onoff task: offlined 9
> [ 23.461009] rcu-torture:torture_onoff task: offlining 10
> [ 23.603210] smpboot: CPU 10 is now offline
> [ 23.627577] rcu-torture:torture_onoff task: offlined 10
> [ 24.627009] rcu-torture:torture_onoff task: onlining 6
> [ 24.675485] smpboot: Booting Node 0 Processor 6 APIC 0x6
> [ 24.789151] rcu-torture:torture_onoff task: onlined 6
> [ 25.789025] rcu-torture:torture_onoff task: offlining 14
> [ 25.858243] smpboot: CPU 14 is now offline
> [ 25.867988] rcu-torture:torture_onoff task: offlined 14
> [ 26.870062] rcu-torture:torture_onoff task: offlining 1
> [ 26.925293] smpboot: CPU 1 is now offline
> [ 26.978849] rcu-torture:torture_onoff task: offlined 1
> [ 28.979064] rcu-torture:torture_onoff task: onlining 10
> [ 29.032704] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 29.059317] rcu-torture:torture_onoff task: onlined 10
> [ 30.059084] rcu-torture:torture_onoff task: onlining 14
> [ 30.112682] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 30.137343] rcu-torture:torture_onoff task: onlined 14
> [ 31.137078] rcu-torture:torture_onoff task: offlining 14
> [ 31.166070] smpboot: CPU 14 is now offline
> [ 31.219937] rcu-torture:torture_onoff task: offlined 14
> [ 32.220012] rcu-torture:torture_onoff task: offlining 8
> [ 32.256561] smpboot: CPU 8 is now offline
> [ 32.261886] rcu-torture:torture_onoff task: offlined 8
> [ 33.262016] rcu-torture:torture_onoff task: offlining 12
> [ 33.380237] smpboot: CPU 12 is now offline
> [ 33.423113] rcu-torture:torture_onoff task: offlined 12
> [ 34.423009] rcu-torture:torture_onoff task: offlining 10
> [ 34.466212] smpboot: CPU 10 is now offline
> [ 34.471595] rcu-torture:torture_onoff task: offlined 10
> [ 35.471008] rcu-torture:torture_onoff task: onlining 3
> [ 35.479539] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 35.508119] rcu-torture:torture_onoff task: onlined 3
> [ 36.509009] rcu-torture:torture_onoff task: onlining 5
> [ 36.563589] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 36.588315] rcu-torture:torture_onoff task: onlined 5
> [ 38.589069] rcu-torture:torture_onoff task: offlining 5
> [ 38.644261] smpboot: CPU 5 is now offline
> [ 38.698930] rcu-torture:torture_onoff task: offlined 5
> [ 39.699060] rcu-torture:torture_onoff task: offlining 4
> [ 39.754291] smpboot: CPU 4 is now offline
> [ 39.808637] rcu-torture:torture_onoff task: offlined 4
> [ 40.809021] rcu-torture:torture_onoff task: offlining 11
> [ 40.865225] smpboot: CPU 11 is now offline
> [ 40.919552] rcu-torture:torture_onoff task: offlined 11
> [ 41.939673] rcu-torture:torture_onoff task: onlining 11
> [ 41.948489] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 42.031085] rcu-torture:torture_onoff task: onlined 11
> [ 43.031008] rcu-torture:torture_onoff task: onlining 4
> [ 43.039562] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 43.129117] rcu-torture:torture_onoff task: onlined 4
> [ 44.142784] rcu-torture:torture_onoff task: onlining 5
> [ 44.188584] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 44.257115] rcu-torture:torture_onoff task: onlined 5
> [ 45.257008] rcu-torture:torture_onoff task: onlining 14
> [ 45.278452] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 45.445125] rcu-torture:torture_onoff task: onlined 14
> [ 47.445009] rcu-torture:torture_onoff task: onlining 9
> [ 47.499476] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 47.533228] rcu-torture:torture_onoff task: onlined 9
> [ 48.533037] rcu-torture:torture_onoff task: onlining 10
> [ 48.587760] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 48.625191] rcu-torture:torture_onoff task: onlined 10
> [ 49.625023] rcu-torture:torture_onoff task: offlining 3
> [ 49.684242] smpboot: CPU 3 is now offline
> [ 49.739836] rcu-torture:torture_onoff task: offlined 3
> [ 50.740027] rcu-torture:torture_onoff task: onlining 3
> [ 50.795725] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 50.825193] rcu-torture:torture_onoff task: onlined 3
> [ 51.839424] rcu-torture:torture_onoff task: offlining 10
> [ 51.863245] smpboot: CPU 10 is now offline
> [ 51.907767] rcu-torture:torture_onoff task: offlined 10
> [ 52.908012] rcu-torture:torture_onoff task: onlining 8
> [ 52.954756] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 53.045171] rcu-torture:torture_onoff task: onlined 8
> [ 54.045023] rcu-torture:torture_onoff task: offlining 13
> [ 54.097238] smpboot: CPU 13 is now offline
> [ 54.131066] rcu-torture:torture_onoff task: offlined 13
> [ 55.131011] rcu-torture:torture_onoff task: offlining 9
> [ 55.176245] smpboot: CPU 9 is now offline
> [ 55.181098] rcu-torture:torture_onoff task: offlined 9
> [ 56.181027] rcu-torture:torture_onoff task: onlining 10
> [ 56.236916] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 56.283185] rcu-torture:torture_onoff task: onlined 10
> [ 57.283030] rcu-torture:torture_onoff task: onlining 2
> [ 57.352121] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 57.414115] rcu-torture:torture_onoff task: onlined 2
> [ 58.415028] rcu-torture:torture_onoff task: onlining 1
> [ 58.472096] x86: Booting SMP configuration:
> [ 58.472545] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 58.508573] rcu-torture:torture_onoff task: onlined 1
> [ 59.510021] rcu-torture:torture_onoff task: offlining 4
> [ 59.588298] smpboot: CPU 4 is now offline
> [ 59.643851] rcu-torture:torture_onoff task: offlined 4
> [ 60.645012] rcu-torture:torture_onoff task: offlining 14
> [ 60.728261] smpboot: CPU 14 is now offline
> [ 60.783787] rcu-torture:torture_onoff task: offlined 14
> [ 61.158025] rcu-torture: rtc: ffffffff820d7030 ver: 493 tfle: 0 rta: 493 rtaf: 0 rtf: 484 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 211179 onoff: 23/23:29/29 37,189:38,232 2550:2997 (HZ=1000) barrier: 0/0:0 cbflood: 118
> [ 61.160296] rcu-torture: Reader Pipe: 1606911908 2853 0 0 0 0 0 0 0 0 0
> [ 61.161231] rcu-torture: Reader Batch: 1564038099 42876662 0 0 0 0 0 0 0 0 0
> [ 61.162222] rcu-torture: Free-Block Circulation: 492 492 491 490 489 488 487 486 485 484 0
> [ 61.784011] rcu-torture:torture_onoff task: onlining 13
> [ 61.817712] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 62.001153] rcu-torture:torture_onoff task: onlined 13
> [ 63.001013] rcu-torture:torture_onoff task: offlining 1
> [ 63.103245] smpboot: CPU 1 is now offline
> [ 63.109824] rcu-torture:torture_onoff task: offlined 1
> [ 64.152203] rcu-torture:torture_onoff task: offlining 10
> [ 64.185213] smpboot: CPU 10 is now offline
> [ 64.189763] rcu-torture:torture_onoff task: offlined 10
> [ 65.190026] rcu-torture:torture_onoff task: onlining 9
> [ 65.216015] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 65.434160] rcu-torture:torture_onoff task: onlined 9
> [ 66.434014] rcu-torture:torture_onoff task: onlining 12
> [ 66.488805] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 66.532942] rcu-torture:torture_onoff task: onlined 12
> [ 67.533021] rcu-torture:torture_onoff task: offlining 3
> [ 67.599534] smpboot: CPU 3 is now offline
> [ 67.655672] rcu-torture:torture_onoff task: offlined 3
> [ 68.656019] rcu-torture:torture_onoff task: onlining 15
> [ 68.712267] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 68.763417] rcu-torture:torture_onoff task: onlined 15
> [ 69.764019] rcu-torture:torture_onoff task: offlining 15
> [ 69.819284] smpboot: CPU 15 is now offline
> [ 69.873984] rcu-torture:torture_onoff task: offlined 15
> [ 70.874012] rcu-torture:torture_onoff task: onlining 3
> [ 70.949074] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 70.983208] rcu-torture:torture_onoff task: onlined 3
> [ 71.983022] rcu-torture:torture_onoff task: onlining 10
> [ 72.009076] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 72.207488] rcu-torture:torture_onoff task: onlined 10
> [ 73.208011] rcu-torture:torture_onoff task: offlining 5
> [ 73.239256] smpboot: CPU 5 is now offline
> [ 73.243935] rcu-torture:torture_onoff task: offlined 5
> [ 74.244019] rcu-torture:torture_onoff task: onlining 4
> [ 74.252811] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 74.563168] rcu-torture:torture_onoff task: onlined 4
> [ 75.563012] rcu-torture:torture_onoff task: offlining 6
> [ 75.600357] smpboot: CPU 6 is now offline
> [ 75.625881] rcu-torture:torture_onoff task: offlined 6
> [ 76.626008] rcu-torture:torture_onoff task: offlining 11
> [ 76.634187] smpboot: CPU 11 is now offline
> [ 76.641088] rcu-torture:torture_onoff task: offlined 11
> [ 77.641015] rcu-torture:torture_onoff task: offlining 2
> [ 77.649235] smpboot: CPU 2 is now offline
> [ 77.655925] rcu-torture:torture_onoff task: offlined 2
> [ 78.656017] rcu-torture:torture_onoff task: offlining 13
> [ 78.666080] smpboot: CPU 13 is now offline
> [ 78.672926] rcu-torture:torture_onoff task: offlined 13
> [ 79.673018] rcu-torture:torture_onoff task: offlining 9
> [ 79.680209] smpboot: CPU 9 is now offline
> [ 79.686833] rcu-torture:torture_onoff task: offlined 9
> [ 80.687010] rcu-torture:torture_onoff task: onlining 9
> [ 80.695536] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 80.722115] rcu-torture:torture_onoff task: onlined 9
> [ 81.722009] rcu-torture:torture_onoff task: offlining 10
> [ 81.804173] smpboot: CPU 10 is now offline
> [ 81.808697] rcu-torture:torture_onoff task: offlined 10
> [ 82.809011] rcu-torture:torture_onoff task: onlining 13
> [ 82.817598] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 82.992126] rcu-torture:torture_onoff task: onlined 13
> [ 83.992009] rcu-torture:torture_onoff task: onlining 1
> [ 84.024124] x86: Booting SMP configuration:
> [ 84.024445] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 84.253120] rcu-torture:torture_onoff task: onlined 1
> [ 85.253012] rcu-torture:torture_onoff task: offlining 8
> [ 85.353204] smpboot: CPU 8 is now offline
> [ 85.403738] rcu-torture:torture_onoff task: offlined 8
> [ 86.404008] rcu-torture:torture_onoff task: onlining 15
> [ 86.458466] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 86.485146] rcu-torture:torture_onoff task: onlined 15
> [ 87.485026] rcu-torture:torture_onoff task: onlining 8
> [ 87.539695] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 87.597212] rcu-torture:torture_onoff task: onlined 8
> [ 88.597022] rcu-torture:torture_onoff task: onlining 2
> [ 88.652738] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 88.693197] rcu-torture:torture_onoff task: onlined 2
> [ 89.693018] rcu-torture:torture_onoff task: offlining 12
> [ 89.749592] smpboot: CPU 12 is now offline
> [ 89.804730] rcu-torture:torture_onoff task: offlined 12
> [ 90.805021] rcu-torture:torture_onoff task: offlining 7
> [ 90.878281] smpboot: CPU 7 is now offline
> [ 90.933559] rcu-torture:torture_onoff task: offlined 7
> [ 91.933009] rcu-torture:torture_onoff task: offlining 2
> [ 92.041205] smpboot: CPU 2 is now offline
> [ 92.085497] rcu-torture:torture_onoff task: offlined 2
> [ 93.085012] rcu-torture:torture_onoff task: onlining 14
> [ 93.092669] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 93.195163] rcu-torture:torture_onoff task: onlined 14
> [ 94.206214] rcu-torture:torture_onoff task: onlining 10
> [ 94.214679] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 94.335117] rcu-torture:torture_onoff task: onlined 10
> [ 95.335009] rcu-torture:torture_onoff task: onlining 5
> [ 95.343523] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 95.428133] rcu-torture:torture_onoff task: onlined 5
> [ 97.428020] rcu-torture:torture_onoff task: onlining 11
> [ 97.482836] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 97.509239] rcu-torture:torture_onoff task: onlined 11
> [ 98.509045] rcu-torture:torture_onoff task: offlining 4
> [ 98.563737] smpboot: CPU 4 is now offline
> [ 98.618051] rcu-torture:torture_onoff task: offlined 4
> [ 99.618042] rcu-torture:torture_onoff task: offlining 13
> [ 99.689524] smpboot: CPU 13 is now offline
> [ 99.744813] rcu-torture:torture_onoff task: offlined 13
> [ 100.745028] rcu-torture:torture_onoff task: offlining 5
> [ 100.800212] smpboot: CPU 5 is now offline
> [ 100.854566] rcu-torture:torture_onoff task: offlined 5
> [ 101.854007] rcu-torture:torture_onoff task: onlining 12
> [ 101.878507] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 101.971166] rcu-torture:torture_onoff task: onlined 12
> [ 102.971012] rcu-torture:torture_onoff task: offlining 1
> [ 103.147591] smpboot: CPU 1 is now offline
> [ 103.152829] rcu-torture:torture_onoff task: offlined 1
> [ 104.153008] rcu-torture:torture_onoff task: onlining 4
> [ 104.168508] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 104.320120] rcu-torture:torture_onoff task: onlined 4
> [ 105.320012] rcu-torture:torture_onoff task: onlining 5
> [ 105.348790] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 105.408758] rcu-torture:torture_onoff task: onlined 5
> [ 106.409013] rcu-torture:torture_onoff task: offlining 5
> [ 106.464247] smpboot: CPU 5 is now offline
> [ 106.518638] rcu-torture:torture_onoff task: offlined 5
> [ 107.520011] rcu-torture:torture_onoff task: onlining 2
> [ 107.574734] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 107.605173] rcu-torture:torture_onoff task: onlined 2
> [ 108.606012] rcu-torture:torture_onoff task: onlining 13
> [ 108.660778] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 108.701176] rcu-torture:torture_onoff task: onlined 13
> [ 109.701020] rcu-torture:torture_onoff task: onlining 5
> [ 109.755826] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 109.842203] rcu-torture:torture_onoff task: onlined 5
> [ 110.842042] rcu-torture:torture_onoff task: offlining 11
> [ 110.962787] smpboot: CPU 11 is now offline
> [ 111.018932] rcu-torture:torture_onoff task: offlined 11
> [ 112.019012] rcu-torture:torture_onoff task: offlining 13
> [ 112.084250] smpboot: CPU 13 is now offline
> [ 112.136796] rcu-torture:torture_onoff task: offlined 13
> [ 113.137012] rcu-torture:torture_onoff task: offlining 12
> [ 113.154984] smpboot: CPU 12 is now offline
> [ 113.160855] rcu-torture:torture_onoff task: offlined 12
> [ 114.161011] rcu-torture:torture_onoff task: offlining 8
> [ 114.264240] smpboot: CPU 8 is now offline
> [ 114.276779] rcu-torture:torture_onoff task: offlined 8
> [ 116.277011] rcu-torture:torture_onoff task: offlining 5
> [ 116.333258] smpboot: CPU 5 is now offline
> [ 116.387757] rcu-torture:torture_onoff task: offlined 5
> [ 117.388014] rcu-torture:torture_onoff task: onlining 6
> [ 117.442499] smpboot: Booting Node 0 Processor 6 APIC 0x6
> [ 117.470138] rcu-torture:torture_onoff task: onlined 6
> [ 118.470013] rcu-torture:torture_onoff task: offlining 2
> [ 118.525211] smpboot: CPU 2 is now offline
> [ 118.529547] rcu-torture:torture_onoff task: offlined 2
> [ 119.529012] rcu-torture:torture_onoff task: onlining 11
> [ 119.537631] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 119.564166] rcu-torture:torture_onoff task: onlined 11
> [ 120.564011] rcu-torture:torture_onoff task: offlining 14
> [ 120.619237] smpboot: CPU 14 is now offline
> [ 120.673701] rcu-torture:torture_onoff task: offlined 14
> [ 121.163011] rcu-torture: rtc: ffffffff820d6b80 ver: 972 tfle: 0 rta: 972 rtaf: 0 rtf: 963 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 427620 onoff: 48/48:56/56 35,319:14,232 5863:5519 (HZ=1000) barrier: 0/0:0 cbflood: 236
> [ 121.164580] rcu-torture: Reader Pipe: 3205717609 5572 0 0 0 0 0 0 0 0 0
> [ 121.165245] rcu-torture: Reader Batch: 3130266830 75456351 0 0 0 0 0 0 0 0 0
> [ 121.165928] rcu-torture: Free-Block Circulation: 971 971 970 969 968 967 966 965 964 963 0
> [ 121.674012] rcu-torture:torture_onoff task: onlining 13
> [ 121.682646] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 121.760166] rcu-torture:torture_onoff task: onlined 13
> [ 122.760013] rcu-torture:torture_onoff task: onlining 8
> [ 122.769709] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 122.796168] rcu-torture:torture_onoff task: onlined 8
> [ 123.796012] rcu-torture:torture_onoff task: offlining 13
> [ 123.911235] smpboot: CPU 13 is now offline
> [ 123.955786] rcu-torture:torture_onoff task: offlined 13
> [ 124.956012] rcu-torture:torture_onoff task: onlining 13
> [ 124.976740] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 125.064167] rcu-torture:torture_onoff task: onlined 13
> [ 126.064011] rcu-torture:torture_onoff task: offlining 8
> [ 126.237225] smpboot: CPU 8 is now offline
> [ 126.291774] rcu-torture:torture_onoff task: offlined 8
> [ 127.293014] rcu-torture:torture_onoff task: onlining 12
> [ 127.348537] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 127.375208] rcu-torture:torture_onoff task: onlined 12
> [ 128.375075] rcu-torture:torture_onoff task: offlining 12
> [ 128.428324] smpboot: CPU 12 is now offline
> [ 128.481630] rcu-torture:torture_onoff task: offlined 12
> [ 129.482056] rcu-torture:torture_onoff task: onlining 5
> [ 129.536575] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 129.562253] rcu-torture:torture_onoff task: onlined 5
> [ 130.562063] rcu-torture:torture_onoff task: onlining 8
> [ 130.616613] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 130.643248] rcu-torture:torture_onoff task: onlined 8
> [ 131.643021] rcu-torture:torture_onoff task: offlining 5
> [ 131.755237] smpboot: CPU 5 is now offline
> [ 131.770580] rcu-torture:torture_onoff task: offlined 5
> [ 132.772010] rcu-torture:torture_onoff task: offlining 11
> [ 132.831224] smpboot: CPU 11 is now offline
> [ 132.835566] rcu-torture:torture_onoff task: offlined 11
> [ 133.835008] rcu-torture:torture_onoff task: offlining 10
> [ 133.876259] smpboot: CPU 10 is now offline
> [ 133.880526] rcu-torture:torture_onoff task: offlined 10
> [ 134.880010] rcu-torture:torture_onoff task: offlining 3
> [ 134.977633] smpboot: CPU 3 is now offline
> [ 134.982503] rcu-torture:torture_onoff task: offlined 3
> [ 135.982008] rcu-torture:torture_onoff task: offlining 4
> [ 136.059186] smpboot: CPU 4 is now offline
> [ 136.072155] rcu-torture:torture_onoff task: offlined 4
> [ 137.072011] rcu-torture:torture_onoff task: onlining 14
> [ 137.080403] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 137.108127] rcu-torture:torture_onoff task: onlined 14
> [ 138.108010] rcu-torture:torture_onoff task: onlining 1
> [ 138.162404] x86: Booting SMP configuration:
> [ 138.162726] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 138.187156] rcu-torture:torture_onoff task: onlined 1
> [ 139.187026] rcu-torture:torture_onoff task: onlining 11
> [ 139.241678] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 139.266211] rcu-torture:torture_onoff task: onlined 11
> [ 140.266085] rcu-torture:torture_onoff task: offlining 14
> [ 140.324971] smpboot: CPU 14 is now offline
> [ 140.379519] rcu-torture:torture_onoff task: offlined 14
> [ 141.379013] rcu-torture:torture_onoff task: onlining 10
> [ 141.387463] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 141.621164] rcu-torture:torture_onoff task: onlined 10
> [ 142.621011] rcu-torture:torture_onoff task: onlining 12
> [ 142.629728] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 142.753171] rcu-torture:torture_onoff task: onlined 12
> [ 143.753012] rcu-torture:torture_onoff task: onlining 7
> [ 143.793773] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 143.850176] rcu-torture:torture_onoff task: onlined 7
> [ 144.850014] rcu-torture:torture_onoff task: offlining 8
> [ 144.925278] smpboot: CPU 8 is now offline
> [ 144.972839] rcu-torture:torture_onoff task: offlined 8
> [ 145.973432] rcu-torture:torture_onoff task: offlining 1
> [ 145.988224] smpboot: CPU 1 is now offline
> [ 145.992547] rcu-torture:torture_onoff task: offlined 1
> [ 146.992070] rcu-torture:torture_onoff task: onlining 1
> [ 147.046569] x86: Booting SMP configuration:
> [ 147.046951] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 147.071234] rcu-torture:torture_onoff task: onlined 1
> [ 148.071082] rcu-torture:torture_onoff task: onlining 8
> [ 148.125583] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 148.246253] rcu-torture:torture_onoff task: onlined 8
> [ 149.246087] rcu-torture:torture_onoff task: offlining 6
> [ 149.301397] smpboot: CPU 6 is now offline
> [ 149.355742] rcu-torture:torture_onoff task: offlined 6
> [ 150.356083] rcu-torture:torture_onoff task: offlining 9
> [ 150.411331] smpboot: CPU 9 is now offline
> [ 150.465602] rcu-torture:torture_onoff task: offlined 9
> [ 151.466027] rcu-torture:torture_onoff task: onlining 4
> [ 151.506652] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 151.607282] rcu-torture:torture_onoff task: onlined 4
> [ 152.607013] rcu-torture:torture_onoff task: offlining 4
> [ 152.619229] smpboot: CPU 4 is now offline
> [ 152.623673] rcu-torture:torture_onoff task: offlined 4
> [ 153.624012] rcu-torture:torture_onoff task: offlining 10
> [ 153.642208] smpboot: CPU 10 is now offline
> [ 153.646624] rcu-torture:torture_onoff task: offlined 10
> [ 154.647009] rcu-torture:torture_onoff task: onlining 6
> [ 154.672468] smpboot: Booting Node 0 Processor 6 APIC 0x6
> [ 154.952173] rcu-torture:torture_onoff task: onlined 6
> [ 155.952011] rcu-torture:torture_onoff task: offlining 7
> [ 155.998230] smpboot: CPU 7 is now offline
> [ 156.040732] rcu-torture:torture_onoff task: offlined 7
> [ 157.041007] rcu-torture:torture_onoff task: onlining 14
> [ 157.095463] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 157.123126] rcu-torture:torture_onoff task: onlined 14
> [ 158.124008] rcu-torture:torture_onoff task: onlining 10
> [ 158.179465] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 158.208159] rcu-torture:torture_onoff task: onlined 10
> [ 159.209012] rcu-torture:torture_onoff task: offlining 11
> [ 159.288513] smpboot: CPU 11 is now offline
> [ 159.342602] rcu-torture:torture_onoff task: offlined 11
> [ 161.343028] rcu-torture:torture_onoff task: offlining 10
> [ 161.532630] smpboot: CPU 10 is now offline
> [ 161.538953] rcu-torture:torture_onoff task: offlined 10
> [ 162.539012] rcu-torture:torture_onoff task: onlining 9
> [ 162.592954] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 162.691169] rcu-torture:torture_onoff task: onlined 9
> [ 163.699428] rcu-torture:torture_onoff task: offlining 12
> [ 163.787094] smpboot: CPU 12 is now offline
> [ 163.791727] rcu-torture:torture_onoff task: offlined 12
> [ 164.792008] rcu-torture:torture_onoff task: onlining 2
> [ 164.832477] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 164.926143] rcu-torture:torture_onoff task: onlined 2
> [ 165.926008] rcu-torture:torture_onoff task: offlining 13
> [ 165.977219] smpboot: CPU 13 is now offline
> [ 165.983491] rcu-torture:torture_onoff task: offlined 13
> [ 166.983009] rcu-torture:torture_onoff task: onlining 11
> [ 167.037444] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 167.091149] rcu-torture:torture_onoff task: onlined 11
> [ 168.091022] rcu-torture:torture_onoff task: onlining 13
> [ 168.146672] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 168.205181] rcu-torture:torture_onoff task: onlined 13
> [ 169.205020] rcu-torture:torture_onoff task: offlining 2
> [ 169.261253] smpboot: CPU 2 is now offline
> [ 169.316811] rcu-torture:torture_onoff task: offlined 2
> [ 170.317021] rcu-torture:torture_onoff task: onlining 10
> [ 170.372697] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 170.426193] rcu-torture:torture_onoff task: onlined 10
> [ 171.426012] rcu-torture:torture_onoff task: onlining 5
> [ 171.471808] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 171.589994] rcu-torture:torture_onoff task: onlined 5
> [ 172.590013] rcu-torture:torture_onoff task: onlining 2
> [ 172.598761] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 172.751166] rcu-torture:torture_onoff task: onlined 2
> [ 173.751011] rcu-torture:torture_onoff task: onlining 3
> [ 173.805841] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 174.070161] rcu-torture:torture_onoff task: onlined 3
> [ 175.080195] rcu-torture:torture_onoff task: offlining 5
> [ 175.179614] smpboot: CPU 5 is now offline
> [ 175.186036] rcu-torture:torture_onoff task: offlined 5
> [ 176.186026] rcu-torture:torture_onoff task: offlining 10
> [ 176.252265] smpboot: CPU 10 is now offline
> [ 176.306864] rcu-torture:torture_onoff task: offlined 10
> [ 178.307012] rcu-torture:torture_onoff task: offlining 9
> [ 178.398309] smpboot: CPU 9 is now offline
> [ 178.452600] rcu-torture:torture_onoff task: offlined 9
> [ 179.453008] rcu-torture:torture_onoff task: offlining 3
> [ 179.508214] smpboot: CPU 3 is now offline
> [ 179.562522] rcu-torture:torture_onoff task: offlined 3
> [ 180.562008] rcu-torture:torture_onoff task: offlining 14
> [ 180.617202] smpboot: CPU 14 is now offline
> [ 180.671471] rcu-torture:torture_onoff task: offlined 14
> [ 181.166014] rcu-torture: rtc: ffffffff820d6760 ver: 1451 tfle: 0 rta: 1451 rtaf: 0 rtf: 1442 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 640476 onoff: 74/74:82/82 35,319:14,232 9128:8228 (HZ=1000) barrier: 0/0:0 cbflood: 352
> [ 181.168279] rcu-torture: Reader Pipe: 4782759012 8318 0 0 0 0 0 0 0 0 0
> [ 181.169233] rcu-torture: Reader Batch: 4672385735 110381595 0 0 0 0 0 0 0 0 0
> [ 181.170216] rcu-torture: Free-Block Circulation: 1450 1450 1449 1448 1447 1446 1445 1444 1443 1442 0
> [ 181.692232] rcu-torture:torture_onoff task: onlining 10
> [ 181.754674] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 181.833162] rcu-torture:torture_onoff task: onlined 10
> [ 182.833013] rcu-torture:torture_onoff task: offlining 8
> [ 182.899242] smpboot: CPU 8 is now offline
> [ 182.941036] rcu-torture:torture_onoff task: offlined 8
> [ 183.964159] rcu-torture:torture_onoff task: offlining 6
> [ 183.984255] smpboot: CPU 6 is now offline
> [ 183.988894] rcu-torture:torture_onoff task: offlined 6
> [ 184.989013] rcu-torture:torture_onoff task: onlining 5
> [ 185.026816] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 185.058174] rcu-torture:torture_onoff task: onlined 5
> [ 186.058022] rcu-torture:torture_onoff task: offlining 5
> [ 186.087219] smpboot: CPU 5 is now offline
> [ 186.091684] rcu-torture:torture_onoff task: offlined 5
> [ 187.092028] rcu-torture:torture_onoff task: onlining 5
> [ 187.147618] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 187.177207] rcu-torture:torture_onoff task: onlined 5
> [ 188.177014] rcu-torture:torture_onoff task: onlining 4
> [ 191.251478] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 191.400144] rcu-torture:torture_onoff task: onlined 4
> [ 192.400012] rcu-torture:torture_onoff task: offlining 4
> [ 192.569230] smpboot: CPU 4 is now offline
> [ 192.573752] rcu-torture:torture_onoff task: offlined 4
> [ 193.574011] rcu-torture:torture_onoff task: onlining 4
> [ 193.583672] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 193.673166] rcu-torture:torture_onoff task: onlined 4
> [ 194.673021] rcu-torture:torture_onoff task: onlining 3
> [ 194.698722] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 194.900169] rcu-torture:torture_onoff task: onlined 3
> [ 195.900011] rcu-torture:torture_onoff task: offlining 1
> [ 195.923236] smpboot: CPU 1 is now offline
> [ 195.928847] rcu-torture:torture_onoff task: offlined 1
> [ 196.929012] rcu-torture:torture_onoff task: onlining 14
> [ 196.983708] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 197.006351] rcu-torture:torture_onoff task: onlined 14
> [ 198.006015] rcu-torture:torture_onoff task: offlining 11
> [ 198.061232] smpboot: CPU 11 is now offline
> [ 198.115789] rcu-torture:torture_onoff task: offlined 11
> [ 199.116014] rcu-torture:torture_onoff task: onlining 6
> [ 199.170674] smpboot: Booting Node 0 Processor 6 APIC 0x6
> [ 199.193338] rcu-torture:torture_onoff task: onlined 6
> [ 200.193014] rcu-torture:torture_onoff task: offlining 15
> [ 200.248238] smpboot: CPU 15 is now offline
> [ 200.302540] rcu-torture:torture_onoff task: offlined 15
> [ 201.302008] rcu-torture:torture_onoff task: onlining 8
> [ 201.310466] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 201.422183] rcu-torture:torture_onoff task: onlined 8
> [ 202.422013] rcu-torture:torture_onoff task: offlining 14
> [ 202.548257] smpboot: CPU 14 is now offline
> [ 202.594923] rcu-torture:torture_onoff task: offlined 14
> [ 203.595023] rcu-torture:torture_onoff task: offlining 2
> [ 203.659226] smpboot: CPU 2 is now offline
> [ 203.706239] rcu-torture:torture_onoff task: offlined 2
> [ 204.706011] rcu-torture:torture_onoff task: offlining 4
> [ 204.739154] smpboot: CPU 4 is now offline
> [ 204.743676] rcu-torture:torture_onoff task: offlined 4
> [ 205.744016] rcu-torture:torture_onoff task: onlining 4
> [ 205.752612] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 205.793165] rcu-torture:torture_onoff task: onlined 4
> [ 206.793016] rcu-torture:torture_onoff task: onlining 1
> [ 206.848662] x86: Booting SMP configuration:
> [ 206.849145] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 206.902207] rcu-torture:torture_onoff task: onlined 1
> [ 207.902020] rcu-torture:torture_onoff task: onlining 12
> [ 207.957701] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 207.986192] rcu-torture:torture_onoff task: onlined 12
> [ 208.986079] rcu-torture:torture_onoff task: offlining 4
> [ 209.092090] smpboot: CPU 4 is now offline
> [ 209.146701] rcu-torture:torture_onoff task: offlined 4
> [ 210.147068] rcu-torture:torture_onoff task: offlining 8
> [ 210.215055] smpboot: CPU 8 is now offline
> [ 210.269872] rcu-torture:torture_onoff task: offlined 8
> [ 211.270011] rcu-torture:torture_onoff task: onlining 9
> [ 211.279694] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 211.419172] rcu-torture:torture_onoff task: onlined 9
> [ 212.449010] rcu-torture:torture_onoff task: onlining 7
> [ 212.457481] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 212.686120] rcu-torture:torture_onoff task: onlined 7
> [ 213.686026] rcu-torture:torture_onoff task: offlining 1
> [ 213.830250] smpboot: CPU 1 is now offline
> [ 213.834810] rcu-torture:torture_onoff task: offlined 1
> [ 214.835012] rcu-torture:torture_onoff task: offlining 7
> [ 214.846257] smpboot: CPU 7 is now offline
> [ 214.850711] rcu-torture:torture_onoff task: offlined 7
> [ 215.851012] rcu-torture:torture_onoff task: offlining 9
> [ 215.866262] smpboot: CPU 9 is now offline
> [ 215.915500] rcu-torture:torture_onoff task: offlined 9
> [ 216.915011] rcu-torture:torture_onoff task: onlining 7
> [ 216.923407] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 216.949146] rcu-torture:torture_onoff task: onlined 7
> [ 217.949009] rcu-torture:torture_onoff task: onlining 1
> [ 218.003444] x86: Booting SMP configuration:
> [ 218.003775] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 218.032159] rcu-torture:torture_onoff task: onlined 1
> [ 219.032015] rcu-torture:torture_onoff task: offlining 6
> [ 219.087239] smpboot: CPU 6 is now offline
> [ 219.141521] rcu-torture:torture_onoff task: offlined 6
> [ 220.141012] rcu-torture:torture_onoff task: onlining 6
> [ 220.149451] smpboot: Booting Node 0 Processor 6 APIC 0x6
> [ 220.175130] rcu-torture:torture_onoff task: onlined 6
> [ 221.175014] rcu-torture:torture_onoff task: offlining 1
> [ 221.230231] smpboot: CPU 1 is now offline
> [ 221.245187] rcu-torture:torture_onoff task: offlined 1
> [ 222.245890] rcu-torture:torture_onoff task: offlining 7
> [ 222.313765] smpboot: CPU 7 is now offline
> [ 222.318570] rcu-torture:torture_onoff task: offlined 7
> [ 223.319033] rcu-torture:torture_onoff task: onlining 7
> [ 223.364428] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 223.534164] rcu-torture:torture_onoff task: onlined 7
> [ 224.534007] rcu-torture:torture_onoff task: onlining 2
> [ 224.542438] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 224.650320] rcu-torture:torture_onoff task: onlined 2
> [ 225.667934] rcu-torture:torture_onoff task: onlining 8
> [ 225.689715] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 226.055186] rcu-torture:torture_onoff task: onlined 8
> [ 227.055016] rcu-torture:torture_onoff task: offlining 7
> [ 227.110245] smpboot: CPU 7 is now offline
> [ 227.164585] rcu-torture:torture_onoff task: offlined 7
> [ 229.164037] rcu-torture:torture_onoff task: offlining 3
> [ 229.222238] smpboot: CPU 3 is now offline
> [ 229.277038] rcu-torture:torture_onoff task: offlined 3
> [ 231.277011] rcu-torture:torture_onoff task: offlining 6
> [ 231.330544] smpboot: CPU 6 is now offline
> [ 231.378858] rcu-torture:torture_onoff task: offlined 6
> [ 232.379622] rcu-torture:torture_onoff task: offlining 5
> [ 232.452196] smpboot: CPU 5 is now offline
> [ 232.506626] rcu-torture:torture_onoff task: offlined 5
> [ 233.507009] rcu-torture:torture_onoff task: offlining 13
> [ 233.681190] smpboot: CPU 13 is now offline
> [ 233.685601] rcu-torture:torture_onoff task: offlined 13
> [ 234.686009] rcu-torture:torture_onoff task: onlining 13
> [ 234.739469] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 234.777109] rcu-torture:torture_onoff task: onlined 13
> [ 235.777009] rcu-torture:torture_onoff task: onlining 7
> [ 235.792560] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 235.894313] rcu-torture:torture_onoff task: onlined 7
> [ 236.894008] rcu-torture:torture_onoff task: offlining 8
> [ 236.949250] smpboot: CPU 8 is now offline
> [ 237.005598] rcu-torture:torture_onoff task: offlined 8
> [ 238.005071] rcu-torture:torture_onoff task: offlining 2
> [ 238.060298] smpboot: CPU 2 is now offline
> [ 238.114455] rcu-torture:torture_onoff task: offlined 2
> [ 239.115009] rcu-torture:torture_onoff task: onlining 4
> [ 239.169339] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 239.196127] rcu-torture:torture_onoff task: onlined 4
> [ 240.196009] rcu-torture:torture_onoff task: onlining 14
> [ 240.250356] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 240.276143] rcu-torture:torture_onoff task: onlined 14
> [ 241.171022] rcu-torture: rtc: ffffffff820d6d30 ver: 1972 tfle: 0 rta: 1972 rtaf: 0 rtf: 1963 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 821755 onoff: 98/98:107/107 34,3223:14,232 15097:10753 (HZ=1000) barrier: 0/0:0 cbflood: 469
> [ 241.172670] rcu-torture: Reader Pipe: 6230009275 11244 0 0 0 0 0 0 0 0 0
> [ 241.173342] rcu-torture: Reader Batch: 6077569610 152450909 0 0 0 0 0 0 0 0 0
> [ 241.174041] rcu-torture: Free-Block Circulation: 1971 1971 1970 1969 1968 1967 1966 1965 1964 1963 0
> [ 241.302095] rcu-torture:torture_onoff task: onlining 15
> [ 241.338408] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 241.403182] rcu-torture:torture_onoff task: onlined 15
> [ 242.403011] rcu-torture:torture_onoff task: onlining 8
> [ 242.411629] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 242.598170] rcu-torture:torture_onoff task: onlined 8
> [ 243.598011] rcu-torture:torture_onoff task: offlining 8
> [ 243.638205] smpboot: CPU 8 is now offline
> [ 243.643015] rcu-torture:torture_onoff task: offlined 8
> [ 244.675380] rcu-torture:torture_onoff task: offlining 15
> [ 244.697825] smpboot: CPU 15 is now offline
> [ 244.703386] rcu-torture:torture_onoff task: offlined 15
> [ 245.703009] rcu-torture:torture_onoff task: offlining 13
> [ 245.836597] smpboot: CPU 13 is now offline
> [ 245.840638] rcu-torture:torture_onoff task: offlined 13
> [ 246.841011] rcu-torture:torture_onoff task: onlining 2
> [ 246.849513] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 246.876125] rcu-torture:torture_onoff task: onlined 2
> [ 247.876013] rcu-torture:torture_onoff task: offlining 14
> [ 247.931174] smpboot: CPU 14 is now offline
> [ 247.986453] rcu-torture:torture_onoff task: offlined 14
> [ 248.986012] rcu-torture:torture_onoff task: onlining 15
> [ 248.994361] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 249.020164] rcu-torture:torture_onoff task: onlined 15
> [ 250.020013] rcu-torture:torture_onoff task: offlining 7
> [ 250.027190] smpboot: CPU 7 is now offline
> [ 250.031444] rcu-torture:torture_onoff task: offlined 7
> [ 251.031008] rcu-torture:torture_onoff task: onlining 5
> [ 251.039363] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 251.065109] rcu-torture:torture_onoff task: onlined 5
> [ 252.065009] rcu-torture:torture_onoff task: onlining 8
> [ 252.200399] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 252.412118] rcu-torture:torture_onoff task: onlined 8
> [ 253.443465] rcu-torture:torture_onoff task: onlining 1
> [ 253.452680] x86: Booting SMP configuration:
> [ 253.453200] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 253.480175] rcu-torture:torture_onoff task: onlined 1
> [ 255.480012] rcu-torture:torture_onoff task: onlining 3
> [ 255.497717] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 255.581151] rcu-torture:torture_onoff task: onlined 3
> [ 256.581019] rcu-torture:torture_onoff task: offlining 12
> [ 256.639488] smpboot: CPU 12 is now offline
> [ 256.696557] rcu-torture:torture_onoff task: offlined 12
> [ 257.697028] rcu-torture:torture_onoff task: offlining 10
> [ 257.792240] smpboot: CPU 10 is now offline
> [ 257.846715] rcu-torture:torture_onoff task: offlined 10
> [ 258.847026] rcu-torture:torture_onoff task: onlining 12
> [ 259.702842] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 259.746426] rcu-torture:torture_onoff task: onlined 12
> [ 260.747028] rcu-torture:torture_onoff task: offlining 2
> [ 261.294198] smpboot: CPU 2 is now offline
> [ 261.298961] rcu-torture:torture_onoff task: offlined 2
> [ 262.337169] rcu-torture:torture_onoff task: onlining 13
> [ 262.373898] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 262.517168] rcu-torture:torture_onoff task: onlined 13
> [ 263.518011] rcu-torture:torture_onoff task: offlining 12
> [ 263.547235] smpboot: CPU 12 is now offline
> [ 263.597744] rcu-torture:torture_onoff task: offlined 12
> [ 264.599177] rcu-torture:torture_onoff task: offlining 15
> [ 264.639259] smpboot: CPU 15 is now offline
> [ 264.685479] rcu-torture:torture_onoff task: offlined 15
> [ 265.705420] rcu-torture:torture_onoff task: onlining 6
> [ 265.723408] smpboot: Booting Node 0 Processor 6 APIC 0x6
> [ 265.769132] rcu-torture:torture_onoff task: onlined 6
> [ 267.769062] rcu-torture:torture_onoff task: offlining 13
> [ 267.824295] smpboot: CPU 13 is now offline
> [ 267.878505] rcu-torture:torture_onoff task: offlined 13
> [ 268.878008] rcu-torture:torture_onoff task: onlining 14
> [ 268.932411] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 268.958155] rcu-torture:torture_onoff task: onlined 14
> [ 269.958015] rcu-torture:torture_onoff task: offlining 1
> [ 270.013265] smpboot: CPU 1 is now offline
> [ 270.067678] rcu-torture:torture_onoff task: offlined 1
> [ 271.068092] rcu-torture:torture_onoff task: onlining 7
> [ 271.122640] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 271.148345] rcu-torture:torture_onoff task: onlined 7
> [ 273.148012] rcu-torture:torture_onoff task: onlining 12
> [ 273.156895] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 273.228932] rcu-torture:torture_onoff task: onlined 12
> [ 274.229627] rcu-torture:torture_onoff task: onlining 9
> [ 274.239860] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 274.335157] rcu-torture:torture_onoff task: onlined 9
> [ 275.335012] rcu-torture:torture_onoff task: offlining 8
> [ 275.383214] smpboot: CPU 8 is now offline
> [ 275.406042] rcu-torture:torture_onoff task: offlined 8
> [ 276.406017] rcu-torture:torture_onoff task: onlining 10
> [ 276.460653] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 276.489140] rcu-torture:torture_onoff task: onlined 10
> [ 277.489039] rcu-torture:torture_onoff task: onlining 13
> [ 277.558410] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 277.587402] rcu-torture:torture_onoff task: onlined 13
> [ 278.588352] rcu-torture:torture_onoff task: onlining 1
> [ 278.642988] x86: Booting SMP configuration:
> [ 278.643476] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 278.682425] rcu-torture:torture_onoff task: onlined 1
> [ 279.683020] rcu-torture:torture_onoff task: offlining 7
> [ 279.739540] smpboot: CPU 7 is now offline
> [ 279.792913] rcu-torture:torture_onoff task: offlined 7
> [ 280.793054] rcu-torture:torture_onoff task: offlining 14
> [ 280.858439] smpboot: CPU 14 is now offline
> [ 280.913004] rcu-torture:torture_onoff task: offlined 14
> [ 281.918280] rcu-torture:torture_onoff task: offlining 5
> [ 281.961289] smpboot: CPU 5 is now offline
> [ 281.966746] rcu-torture:torture_onoff task: offlined 5
> [ 282.967009] rcu-torture:torture_onoff task: onlining 14
> [ 282.978634] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 283.102133] rcu-torture:torture_onoff task: onlined 14
> [ 284.106745] rcu-torture:torture_onoff task: offlining 6
> [ 284.200248] smpboot: CPU 6 is now offline
> [ 284.205012] rcu-torture:torture_onoff task: offlined 6
> [ 286.205019] rcu-torture:torture_onoff task: offlining 9
> [ 286.261333] smpboot: CPU 9 is now offline
> [ 286.267960] rcu-torture:torture_onoff task: offlined 9
> [ 287.268016] rcu-torture:torture_onoff task: onlining 2
> [ 287.322841] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 287.350199] rcu-torture:torture_onoff task: onlined 2
> [ 288.350017] rcu-torture:torture_onoff task: onlining 11
> [ 288.404892] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 288.433392] rcu-torture:torture_onoff task: onlined 11
> [ 289.434021] rcu-torture:torture_onoff task: offlining 4
> [ 289.498357] smpboot: CPU 4 is now offline
> [ 289.551981] rcu-torture:torture_onoff task: offlined 4
> [ 290.552025] rcu-torture:torture_onoff task: offlining 12
> [ 290.608217] smpboot: CPU 12 is now offline
> [ 290.672899] rcu-torture:torture_onoff task: offlined 12
> [ 291.673013] rcu-torture:torture_onoff task: offlining 3
> [ 291.729198] smpboot: CPU 3 is now offline
> [ 291.733673] rcu-torture:torture_onoff task: offlined 3
> [ 292.734013] rcu-torture:torture_onoff task: onlining 9
> [ 292.777604] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 292.885143] rcu-torture:torture_onoff task: onlined 9
> [ 293.885011] rcu-torture:torture_onoff task: onlining 15
> [ 293.893633] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 294.034163] rcu-torture:torture_onoff task: onlined 15
> [ 295.065074] rcu-torture:torture_onoff task: offlining 2
> [ 295.118208] smpboot: CPU 2 is now offline
> [ 295.124735] rcu-torture:torture_onoff task: offlined 2
> [ 296.160078] rcu-torture:torture_onoff task: onlining 4
> [ 296.176467] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 296.346146] rcu-torture:torture_onoff task: onlined 4
> [ 297.346015] rcu-torture:torture_onoff task: onlining 5
> [ 297.400478] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 297.428210] rcu-torture:torture_onoff task: onlined 5
> [ 298.428038] rcu-torture:torture_onoff task: onlining 3
> [ 298.499156] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 298.551823] rcu-torture:torture_onoff task: onlined 3
> [ 300.552021] rcu-torture:torture_onoff task: offlining 10
> [ 300.609517] smpboot: CPU 10 is now offline
> [ 300.664816] rcu-torture:torture_onoff task: offlined 10
> [ 301.174013] rcu-torture: rtc: ffffffff820d63a0 ver: 2525 tfle: 0 rta: 2525 rtaf: 0 rtf: 2516 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1000461 onoff: 124/124:130/130 34,3223:11,552 18699:13272 (HZ=1000) barrier: 0/0:0 cbflood: 588
> [ 301.176369] rcu-torture: Reader Pipe: 7696148438 14411 0 0 0 0 0 0 0 0 0
> [ 301.177314] rcu-torture: Reader Batch: 7505961227 190201622 0 0 0 0 0 0 0 0 0
> [ 301.178302] rcu-torture: Free-Block Circulation: 2524 2524 2523 2522 2521 2520 2519 2518 2517 2516 0
> [ 301.665013] rcu-torture:torture_onoff task: onlining 2
> [ 301.673722] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 301.742192] rcu-torture:torture_onoff task: onlined 2
> [ 302.742013] rcu-torture:torture_onoff task: onlining 7
> [ 302.750787] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 302.833156] rcu-torture:torture_onoff task: onlined 7
> [ 303.833014] rcu-torture:torture_onoff task: offlining 9
> [ 303.868266] smpboot: CPU 9 is now offline
> [ 303.917852] rcu-torture:torture_onoff task: offlined 9
> [ 304.918011] rcu-torture:torture_onoff task: onlining 8
> [ 304.926769] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 305.000154] rcu-torture:torture_onoff task: onlined 8
> [ 306.000014] rcu-torture:torture_onoff task: offlining 4
> [ 306.074862] smpboot: CPU 4 is now offline
> [ 306.079901] rcu-torture:torture_onoff task: offlined 4
> [ 307.081011] rcu-torture:torture_onoff task: onlining 12
> [ 307.135781] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 307.230838] rcu-torture:torture_onoff task: onlined 12
> [ 308.231033] rcu-torture:torture_onoff task: offlining 1
> [ 308.291112] smpboot: CPU 1 is now offline
> [ 308.291635] BUG: unable to handle kernel NULL pointer dereference at (null)
> [ 308.292063] IP: [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 308.292063] PGD 0
> [ 308.292063] Oops: 0002 [#1] PREEMPT SMP
> [ 308.292063] Modules linked in:
> [ 308.292063] CPU: 11 PID: 798 Comm: torture_onoff Not tainted 4.5.0-rc1+ #14
> [ 308.292063] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 308.292063] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
> [ 308.292063] RIP: 0010:[<ffffffff810b9452>] [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 308.292063] RSP: 0018:ffff88007c6f7c98 EFLAGS: 00010086
> [ 308.292063] RAX: dead000000000200 RBX: ffff88007fb6cc00 RCX: ffff88007fa2cc00
> [ 308.292063] RDX: 0000000000000000 RSI: ffff88007fa2d6d0 RDI: ffff88007fb6cc00
> [ 308.292063] RBP: ffff88007c6f7cc0 R08: 0000000000000000 R09: ffffffff81e4d360
> [ 308.292063] R10: ffffea0001f2daa0 R11: 0000000000000000 R12: ffff88007fa2d6d0
> [ 308.292063] R13: ffff88007fb6cc00 R14: 000000000000000b R15: ffff88007fa2c420
> [ 308.292063] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 308.292063] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 308.292063] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 308.292063] Stack:
> [ 308.292063] ffff88007fb6cc00 ffff88007fa2d6d8 ffff88007fa2dad0 ffff88007fa2d8d0
> [ 308.292063] ffff88007fa2d4d8 ffff88007c6f7d08 ffffffff810b95c4 ffff88007fa2cc00
> [ 308.292063] ffff88007fa2d648 00000000fffffff0 ffffffff81e4e0c0 0000000000000007
> [ 308.292063] Call Trace:
> [ 308.292063] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 308.292063] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 308.292063] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 308.292063] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 308.292063] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 308.292063] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 308.292063] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 308.292063] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 308.292063] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 308.292063] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 308.292063] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 308.292063] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 308.292063] Code: 56 41 55 41 54 53 48 8b 06 44 8b 77 40 48 85 c0 74 53 49 89 fd 49 89 f4 4d 8b 3c 24 66 66 66 66 90 49 8b 07 49 8b 57 08 48 85 c0 <48> 89 02 74 04 48 89 50 08 48 b8 00 02 00 00 00 00 ad de 4c 89
> [ 308.292063] RIP [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 308.292063] RSP <ffff88007c6f7c98>
> [ 308.292063] CR2: 0000000000000000
> [ 308.292063] ---[ end trace 29cb5d70ad875872 ]---
> [ 308.292063] note: torture_onoff[798] exited with preempt_count 3
> [ 336.362003] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 336.362003] 3-...: (1 GPs behind) idle=6cf/140000000000000/0 softirq=8341/8345 fqs=7000
> [ 336.362003] 8-...: (1 GPs behind) idle=503/140000000000001/0 softirq=9290/9294 fqs=7000
> [ 336.362003] 11-...: (1 GPs behind) idle=32f/140000000000001/0 softirq=8320/8323 fqs=7001
> [ 336.362003] 12-...: (1 GPs behind) idle=e2f/140000000000000/0 softirq=8014/8017 fqs=7001
> [ 336.362003] (detected by 7, t=21006 jiffies, g=4731, c=4730, q=2)
> [ 336.362003] Task dump for CPU 3:
> [ 336.362003] rcu_torture_rea R running task 14760 782 2 0x00000008
> [ 336.362003] 0000000021ca5292 0000000000000001 00000000cfc06af0 ffff88007c5bfcf0
> [ 336.362003] ffffffff813480d7 ffff88007c5bfd20 ffffffff8133944d ffff88007fb6cc00
> [ 336.362003] 0000000021cadf3e 0000000000000001 00000000cfc06af0 ffff88007c5bfd30
> [ 336.362003] Call Trace:
> [ 336.362003] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 336.362003] [<ffffffff8133944d>] ? delay_tsc+0x1d/0xc0
> [ 336.362003] [<ffffffff8133930a>] ? __delay+0xa/0x10
> [ 336.362003] [<ffffffff810930c7>] ? do_raw_spin_lock+0x87/0x150
> [ 336.362003] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 336.362003] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 336.362003] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 336.362003] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 336.362003] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 336.362003] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 336.362003] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 336.362003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 336.362003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 336.362003] Task dump for CPU 8:
> [ 336.362003] rcu_torture_rea R running task 14760 789 2 0x00000008
> [ 336.362003] ffffffff818af15c ffff88007c0f3ce8 ffff88007cdcbe80 ffff88007c91f080
> [ 336.362003] 0000000000000046 0000000000000000 ffff88007c0f4000 0000000000000000
> [ 336.362003] 00000047648a43ed 000000000000126f ffffffff820d6eb0 ffff88007c0f3d38
> [ 336.362003] Call Trace:
> [ 336.362003] [<ffffffff818af15c>] ? __schedule+0x38c/0xb00
> [ 336.362003] [<ffffffff818afd13>] ? preempt_schedule_irq+0x43/0x60
> [ 336.362003] [<ffffffff818b513b>] ? retint_kernel+0x1b/0x1d
> [ 336.362003] [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 336.362003] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 336.362003] [<ffffffff810ad3ce>] ? rcu_torture_reader+0x11e/0x2e0
> [ 336.362003] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 336.362003] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 336.362003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 336.362003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 336.362003] Task dump for CPU 11:
> [ 336.362003] torture_onoff R running task 13416 798 2 0x00000008
> [ 336.362003] ffffffff8104a8b5 ffff88007ffdb600 ffff88007fb78f70 0000000000000002
> [ 336.362003] 0000000000000000 0000000000000000 ffff88007c6f7be8 ffff88007cafcb00
> [ 336.362003] ffff88007c6f7b70 ffffffff8104aa3e ffff88007c6f7bc8 ffffffff8104ac95
> [ 336.362003] Call Trace:
> [ 336.362003] [<ffffffff8104a8b5>] ? __bad_area_nosemaphore+0x75/0x1f0
> [ 336.362003] [<ffffffff8104aa3e>] ? bad_area_nosemaphore+0xe/0x10
> [ 336.362003] [<ffffffff8104ac95>] ? __do_page_fault+0x85/0x450
> [ 336.362003] [<ffffffff8104b06c>] ? do_page_fault+0xc/0x10
> [ 336.362003] [<ffffffff818b6422>] ? page_fault+0x22/0x30
> [ 336.362003] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 336.362003] [<ffffffff810b95c4>] ? timer_cpu_notify+0xe4/0x160
> [ 336.362003] [<ffffffff81073ea5>] ? notifier_call_chain+0x45/0x70
> [ 336.362003] [<ffffffff81073fc9>] ? __raw_notifier_call_chain+0x9/0x10
> [ 336.362003] [<ffffffff8105759e>] ? cpu_notify_nofail+0x1e/0x30
> [ 336.362003] [<ffffffff81057852>] ? _cpu_down+0x212/0x350
> [ 336.362003] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 336.362003] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 336.362003] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 336.362003] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 336.362003] [<ffffffff810579bf>] ? cpu_down+0x2f/0x50
> [ 336.362003] [<ffffffff811266b5>] ? torture_onoff+0x115/0x380
> [ 336.362003] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 336.362003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 336.362003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 336.362003] Task dump for CPU 12:
> [ 336.362003] rcu_torture_rea R running task 14760 786 2 0x00000008
> [ 336.362003] 0000000021c7f59f 0000000000000001 00000000cfc06af0 ffff88007c0dfcf0
> [ 336.362003] ffffffff813480d7 ffff88007c0dfd20 ffffffff81339448 ffff88007fa2cc00
> [ 336.362003] 0000000021c888b8 0000000000000001 00000000cfc06af0 ffff88007c0dfd30
> [ 336.362003] Call Trace:
> [ 336.362003] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 336.362003] [<ffffffff8133944d>] ? delay_tsc+0x1d/0xc0
> [ 336.362003] [<ffffffff8133930a>] ? __delay+0xa/0x10
> [ 336.362003] [<ffffffff810930c7>] ? do_raw_spin_lock+0x87/0x150
> [ 336.362003] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 336.362003] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 336.362003] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 336.362003] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 336.362003] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 336.362003] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 336.362003] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 336.362003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 336.362003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 336.362003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 361.179014] rcu-torture: rtc: ffffffff820d6fd0 ver: 2590 tfle: 0 rta: 2591 rtaf: 0 rtf: 2581 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1144231 onoff: 128/128:132/133 34,3223:11,552 19099:13437 (HZ=1000) barrier: 0/0:0 cbflood: 608
> [ 361.181325] rcu-torture: Reader Pipe: 8730585935 14768 0 0 0 0 0 0 0 0 0
> [ 361.182261] rcu-torture: Reader Batch: 8415137892 315462811 0 0 0 0 0 0 0 0 0
> [ 361.183234] rcu-torture: Free-Block Circulation: 2590 2589 2588 2587 2586 2585 2584 2583 2582 2581 0
> [ 399.367004] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 399.367004] 3-...: (1 GPs behind) idle=6cf/140000000000000/0 softirq=8341/8345 fqs=27770
> [ 399.367004] 8-...: (1 GPs behind) idle=503/140000000000001/0 softirq=9290/9294 fqs=27770
> [ 399.367004] 11-...: (1 GPs behind) idle=32f/140000000000001/0 softirq=8320/8323 fqs=27770
> [ 399.367004] 12-...: (1 GPs behind) idle=e2f/140000000000000/0 softirq=8014/8017 fqs=27771
> [ 399.367004] (detected by 14, t=84011 jiffies, g=4731, c=4730, q=2)
> [ 399.367004] Task dump for CPU 3:
> [ 399.367004] rcu_torture_rea R running task 14760 782 2 0x00000008
> [ 399.367004] 000000008025ff9c 0000000000000001 00000000cfc06af0 ffff88007c5bfcf0
> [ 399.367004] ffffffff813480d7 ffff88007c5bfd20 ffffffff813394bf ffff88007fb6cc00
> [ 399.367004] 0000000080269050 0000000000000001 00000000cfc06af0 ffff88007c5bfd30
> [ 399.367004] Call Trace:
> [ 399.367004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 399.367004] [<ffffffff8133944d>] ? delay_tsc+0x1d/0xc0
> [ 399.367004] [<ffffffff8133930a>] ? __delay+0xa/0x10
> [ 399.367004] [<ffffffff810930c7>] ? do_raw_spin_lock+0x87/0x150
> [ 399.367004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 399.367004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 399.367004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 399.367004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 399.367004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 399.367004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 399.367004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 399.367004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 399.367004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 399.367004] Task dump for CPU 8:
> [ 399.367004] rcu_torture_rea R running task 14760 789 2 0x00000008
> [ 399.367004] ffffffff818af15c ffff88007c0f3ce8 ffff88007cdcbe80 ffff88007c91f080
> [ 399.367004] 0000000000000046 0000000000000000 ffff88007c0f4000 0000000000000000
> [ 399.367004] 00000047648a43ed 000000000000126f ffffffff820d6eb0 ffff88007c0f3d38
> [ 399.367004] Call Trace:
> [ 399.367004] [<ffffffff818af15c>] ? __schedule+0x38c/0xb00
> [ 399.367004] [<ffffffff818afd13>] ? preempt_schedule_irq+0x43/0x60
> [ 399.367004] [<ffffffff818b513b>] ? retint_kernel+0x1b/0x1d
> [ 399.367004] [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 399.367004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 399.367004] [<ffffffff810ad3ce>] ? rcu_torture_reader+0x11e/0x2e0
> [ 399.367004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 399.367004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 399.367004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 399.367004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 399.367004] Task dump for CPU 11:
> [ 399.367004] torture_onoff R running task 13416 798 2 0x00000008
> [ 399.367004] ffffffff8104a8b5 ffff88007ffdb600 ffff88007fb78f70 0000000000000002
> [ 399.367004] 0000000000000000 0000000000000000 ffff88007c6f7be8 ffff88007cafcb00
> [ 399.367004] ffff88007c6f7b70 ffffffff8104aa3e ffff88007c6f7bc8 ffffffff8104ac95
> [ 399.367004] Call Trace:
> [ 399.367004] [<ffffffff8104a8b5>] ? __bad_area_nosemaphore+0x75/0x1f0
> [ 399.367004] [<ffffffff8104aa3e>] ? bad_area_nosemaphore+0xe/0x10
> [ 399.367004] [<ffffffff8104ac95>] ? __do_page_fault+0x85/0x450
> [ 399.367004] [<ffffffff8104b06c>] ? do_page_fault+0xc/0x10
> [ 399.367004] [<ffffffff818b6422>] ? page_fault+0x22/0x30
> [ 399.367004] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 399.367004] [<ffffffff810b95c4>] ? timer_cpu_notify+0xe4/0x160
> [ 399.367004] [<ffffffff81073ea5>] ? notifier_call_chain+0x45/0x70
> [ 399.367004] [<ffffffff81073fc9>] ? __raw_notifier_call_chain+0x9/0x10
> [ 399.367004] [<ffffffff8105759e>] ? cpu_notify_nofail+0x1e/0x30
> [ 399.367004] [<ffffffff81057852>] ? _cpu_down+0x212/0x350
> [ 399.367004] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 399.367004] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 399.367004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 399.367004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 399.367004] [<ffffffff810579bf>] ? cpu_down+0x2f/0x50
> [ 399.367004] [<ffffffff811266b5>] ? torture_onoff+0x115/0x380
> [ 399.367004] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 399.367004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 399.367004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 399.367004] Task dump for CPU 12:
> [ 399.367004] rcu_torture_rea R running task 14760 786 2 0x00000008
> [ 399.367004] 0000000081556309 0000000000000001 00000000cfc06af0 ffff88007c0dfcf0
> [ 399.367004] ffffffff813480d7 ffff88007c0dfd20 ffffffff81339448 ffff88007fa2cc00
> [ 399.367004] 000000008155f790 0000000000000001 00000000cfc06af0 ffff88007c0dfd30
> [ 399.367004] Call Trace:
> [ 399.367004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 399.367004] [<ffffffff813394bf>] ? delay_tsc+0x8f/0xc0
> [ 399.367004] [<ffffffff8133930a>] ? __delay+0xa/0x10
> [ 399.367004] [<ffffffff810930c7>] ? do_raw_spin_lock+0x87/0x150
> [ 399.367004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 399.367004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 399.367004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 399.367004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 399.367004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 399.367004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 399.367004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 399.367004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 399.367004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 399.367004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 421.184014] rcu-torture: rtc: ffffffff820d6fd0 ver: 2590 tfle: 0 rta: 2591 rtaf: 0 rtf: 2581 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1265617 onoff: 128/128:132/133 34,3223:11,552 19099:13437 (HZ=1000) barrier: 0/0:0 cbflood: 608
> [ 421.186171] rcu-torture: Reader Pipe: 9599676445 14768 0 0 0 0 0 0 0 0 0
> [ 421.187032] rcu-torture: Reader Batch: 9284228402 315462811 0 0 0 0 0 0 0 0 0
> [ 421.187925] rcu-torture: Free-Block Circulation: 2590 2589 2588 2587 2586 2585 2584 2583 2582 2581 0
> [ 421.189059] ??? Writer stall state RTWS_EXP_SYNC(4) g4731 c4730 f0x0
> [ 421.189684] rcu_preempt: wait state: 3 ->state: 0x1
> [ 421.190180] rcu_sched: wait state: 1 ->state: 0x1
> [ 421.190646] rcu_bh: wait state: 1 ->state: 0x1
> [ 421.191099] Dumping ftrace buffer:
> [ 421.191446] (ftrace buffer empty)
> [ 316.386056] BUG: spinlock lockup suspected on CPU#12, rcu_torture_rea/786
> [ 316.386056] lock: 0xffff88007fa2cc00, .magic: dead4ead, .owner: torture_onoff/798, .owner_cpu: 11
> [ 316.386056] CPU: 12 PID: 786 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] ffff88007fa2cc00 ffff88007c0dfd10 ffffffff8132cd6c ffff88007cafcb00
> [ 316.386056] ffff88007c0dfd30 ffffffff81092fb3 ffff88007fa2cc00 00000000cfc06af0
> [ 316.386056] ffff88007c0dfd60 ffffffff810930db 0000000000000286 ffff88007fa2cc00
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 316.386056] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 316.386056] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 316.386056] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 316.386056] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 316.386056] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 316.386056] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 316.386056] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Sending NMI to all CPUs:
> [ 316.386056] NMI backtrace for cpu 0
> [ 316.386056] CPU: 0 PID: 781 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c918c80 ti: ffff88007c5b8000 task.ti: ffff88007c5b8000
> [ 316.386056] RIP: 0010:[<ffffffff81339463>] [<ffffffff81339463>] delay_tsc+0x33/0xc0
> [ 316.386056] RSP: 0018:ffff88007c5bbdb0 EFLAGS: 00000286
> [ 316.386056] RAX: 0000000080000000 RBX: 0000016f89221cb2 RCX: 0000000000000001
> [ 316.386056] RDX: 0000000080000001 RSI: ffffffff81ca0d44 RDI: 00000000ffffffff
> [ 316.386056] RBP: ffff88007c5bbdd0 R08: ffff88007c5b8000 R09: ffff88007fa0cc00
> [ 316.386056] R10: ffff88007c5bbe30 R11: 0000000000000001 R12: 0000016f88f5821e
> [ 316.386056] R13: 000000000034e556 R14: 0000000000000000 R15: ffffffff820d6fd0
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506239dcc8 CR3: 000000007b0ee000 CR4: 00000000000006f0
> [ 316.386056] Stack:
> [ 316.386056] 000000000000000a ffff88007c5bbe20 00000069b5d0f6e7 000000000000127b
> [ 316.386056] ffff88007c5bbde0 ffffffff81339337 ffff88007c5bbe00 ffffffff810add86
> [ 316.386056] 0000000000000000 0000000000000000 ffff88007c5bbea8 ffffffff810ad458
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 316.386056] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 316.386056] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 <bf> 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f
> [ 316.386056] NMI backtrace for cpu 2
> [ 316.386056] CPU: 2 PID: 794 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007cafd780 ti: ffff88007c744000 task.ti: ffff88007c744000
> [ 316.386056] RIP: 0010:[<ffffffff81339463>] [<ffffffff81339463>] delay_tsc+0x33/0xc0
> [ 316.386056] RSP: 0018:ffff88007c747db0 EFLAGS: 00000286
> [ 316.386056] RAX: 0000000080000000 RBX: 0000016f8922659a RCX: 0000000000000001
> [ 316.386056] RDX: 0000000080000001 RSI: ffffffff81ca0d44 RDI: 00000000ffffffff
> [ 316.386056] RBP: ffff88007c747dd0 R08: ffff88007c744000 R09: ffff88007fa4cc00
> [ 316.386056] R10: ffff88007c747e30 R11: 000000000000003c R12: 0000016f890566fe
> [ 316.386056] R13: 0000000000351c70 R14: 0000000000000002 R15: ffffffff820d6fd0
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] 0000000000000010 ffff88007c747e20 00000069b889daa7 000000000000127b
> [ 316.386056] ffff88007c747de0 ffffffff81339337 ffff88007c747e00 ffffffff810add86
> [ 316.386056] 0000000000000000 0000000000000000 ffff88007c747ea8 ffffffff810ad458
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 316.386056] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 316.386056] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 <bf> 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f
> [ 316.386056] NMI backtrace for cpu 3
> [ 316.386056] CPU: 3 PID: 782 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c919900 ti: ffff88007c5bc000 task.ti: ffff88007c5bc000
> [ 316.386056] RIP: 0010:[<ffffffff81348009>] [<ffffffff81348009>] check_preemption_disabled+0x29/0xe0
> [ 316.386056] RSP: 0018:ffff88007c5bfce0 EFLAGS: 00000002
> [ 316.386056] RAX: 0000000000000003 RBX: ffff88007fb6cc00 RCX: 0000000000000002
> [ 316.386056] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 316.386056] RBP: ffff88007c5bfce0 R08: ffffffff81a0a240 R09: ffff88007fb6cc00
> [ 316.386056] R10: ffff88007c5bfe30 R11: 0000000000000400 R12: 00000000cb524812
> [ 316.386056] R13: 0000000000000001 R14: 00000000cfc06af0 R15: ffff88007c5bfdd0
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fa60000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] ffff88007c5bfcf0 ffffffff813480d7 ffff88007c5bfd20 ffffffff8133944d
> [ 316.386056] ffff88007fb6cc00 00000000cb524812 0000000000000001 00000000cfc06af0
> [ 316.386056] ffff88007c5bfd30 ffffffff8133930a ffff88007c5bfd60 ffffffff810930c7
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff813480d7>] debug_smp_processor_id+0x17/0x20
> [ 316.386056] [<ffffffff8133944d>] delay_tsc+0x1d/0xc0
> [ 316.386056] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 316.386056] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 316.386056] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 316.386056] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 316.386056] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 316.386056] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 316.386056] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 00 00 55 65 8b 05 a8 2d cc 7e 48 89 e5 41 56 41 55 41 54 53 65 8b 1d 27 21 cc 7e a9 ff ff ff 7f 74 0b 89 d8 5b 41 5c 41 5d 41 5e <5d> c3 9c 58 f6 c4 02 74 ee 89 d8 83 e0 3f 48 8d 14 c5 08 92 a0
> [ 316.386056] NMI backtrace for cpu 5
> [ 316.386056] CPU: 5 PID: 775 Comm: rcu_torture_wri Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c758000 ti: ffff88007c98c000 task.ti: ffff88007c98c000
> [ 316.386056] RIP: 0010:[<ffffffff810cd5c6>] [<ffffffff810cd5c6>] smp_call_function_single+0x106/0x140
> [ 316.386056] RSP: 0018:ffff88007c98fd50 EFLAGS: 00000202
> [ 316.386056] RAX: 0000000000000001 RBX: 0000000000000009 RCX: 0000000000000000
> [ 316.386056] RDX: 0000000000000000 RSI: ffff88007fab6440 RDI: ffffffff81cbdfe7
> [ 316.386056] RBP: ffff88007c98fd90 R08: ffffffff81a0a320 R09: 0000000000000002
> [ 316.386056] R10: 0000000000000009 R11: 0000000000000c00 R12: ffffffff810af980
> [ 316.386056] R13: ffffffff81e47ac0 R14: 0000000000016440 R15: ffffffff81e48e00
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007faa0000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] 0000000000000000 0000000000000000 0000000000000000 0000000000000003
> [ 316.386056] 000000000000cbb0 0000000000000002 0000000000000000 ffffffff81e47ac0
> [ 316.386056] ffff88007c98fde8 ffffffff810aedbe ffffffff810af980 0000000000000009
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff810aedbe>] sync_rcu_exp_select_cpus+0x1be/0x3d0
> [ 316.386056] [<ffffffff810af980>] ? rcu_seq_end.part.52+0x30/0x30
> [ 316.386056] [<ffffffff810afb9f>] synchronize_rcu_expedited.part.65+0x5f/0xb0
> [ 316.386056] [<ffffffff810afc06>] synchronize_rcu_expedited+0x16/0x40
> [ 316.386056] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 316.386056] [<ffffffff813394bf>] ? delay_tsc+0x8f/0xc0
> [ 316.386056] [<ffffffff81339366>] ? __udelay+0x26/0x30
> [ 316.386056] [<ffffffff810ac5a1>] rcu_torture_writer+0x441/0x6b0
> [ 316.386056] [<ffffffff810ac160>] ? rcu_torture_fakewriter+0x160/0x160
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 5e e4 00 01 eb 86 e8 1a ab 27 00 89 c0 49 c7 c6 40 64 01 00 4c 89 f6 48 03 34 c5 20 f5 f2 81 8b 46 18 a8 01 74 09 f3 90 8b 46 18 <a8> 01 75 f7 83 4e 18 01 89 df 4c 89 e9 4c 89 e2 e8 e5 fd ff ff
> [ 316.386056] NMI backtrace for cpu 7
> [ 316.386056] CPU: 7 PID: 787 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c91d780 ti: ffff88007c750000 task.ti: ffff88007c750000
> [ 316.386056] RIP: 0010:[<ffffffff810ad377>] [<ffffffff810ad377>] rcu_torture_reader+0xc7/0x2e0
> [ 316.386056] RSP: 0018:ffff88007c753e10 EFLAGS: 00000206
> [ 316.386056] RAX: ffffffff81e47800 RBX: ffffffffffffffff RCX: 00000000000493e0
> [ 316.386056] RDX: 0000000000000000 RSI: ffffffff81d29759 RDI: ffffffff81d29759
> [ 316.386056] RBP: ffff88007c753ea8 R08: ffff88007c750000 R09: ffff88007faecc00
> [ 316.386056] R10: ffff88007c753e30 R11: 0000000000000001 R12: 0000000000000000
> [ 316.386056] R13: 00000069ba9b6ec1 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] 0000000000000000 0000000081a0a240 33f80be8f7164cb6 00000000000003e0
> [ 316.386056] 0000000000000000 ffff88007faed1b8 00000001000258ae ffffffff810ad590
> [ 316.386056] 0000000000000000 ffffffff00000007 00000000ffffffff 0000000000000000
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 8f 32 01 00 00 48 c7 c7 59 97 d2 81 4c 29 f3 e8 80 ad 29 00 48 8b 05 69 8a 02 01 48 c7 c7 59 97 d2 81 65 4a ff 04 e5 40 cb 00 00 <48> 83 78 30 01 48 83 db ff e8 5b ad 29 00 48 83 fb 0a b8 0a 00
> [ 316.386056] NMI backtrace for cpu 8
> [ 316.386056] CPU: 8 PID: 789 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c91f080 ti: ffff88007c0f0000 task.ti: ffff88007c0f0000
> [ 316.386056] RIP: 0010:[<ffffffff81339455>] [<ffffffff81339455>] delay_tsc+0x25/0xc0
> [ 316.386056] RSP: 0018:ffff88007fb03d78 EFLAGS: 00000006
> [ 316.386056] RAX: 000000008923865a RBX: ffff88007fb6cc00 RCX: 0000000000000103
> [ 316.386056] RDX: 000000000000016f RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 316.386056] RBP: ffff88007fb03d98 R08: 0000000000000000 R09: 000000000000f9ad
> [ 316.386056] R10: 000000003d550944 R11: 0000000002faf04c R12: 00000000c6d627e6
> [ 316.386056] R13: 0000000000000001 R14: 0000000000000008 R15: 0000000000000000
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fb00000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] ffff88007fb6cc00 00000000c6d627e6 0000000000000001 00000000cfc06af0
> [ 316.386056] ffff88007fb03da8 ffffffff8133930a ffff88007fb03dd8 ffffffff810930c7
> [ 316.386056] ffff88007fb6cc00 ffffffff820d8c80 ffff88007fb6cc00 0000000000000000
> [ 316.386056] Call Trace:
> [ 316.386056] <IRQ> d [<ffffffff8133930a>] __delay+0xa/0x10
> [ 316.386056] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 316.386056] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 316.386056] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 316.386056] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 316.386056] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 316.386056] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 316.386056] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 316.386056] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 316.386056] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 316.386056] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 316.386056] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 316.386056] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 316.386056] <EOI> d [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 316.386056] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 316.386056] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 5e 41 5f 5d c3 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 <48> c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 43
> [ 316.386056] NMI backtrace for cpu 11
> [ 316.386056] CPU: 11 PID: 798 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
> [ 316.386056] RIP: 0010:[<ffffffff810780be>] [<ffffffff810780be>] preempt_count_add+0xe/0xc0
> [ 316.386056] RSP: 0018:ffff88007fb63e30 EFLAGS: 00000086
> [ 316.386056] RAX: 0000000000000001 RBX: ffff88007fb6cc00 RCX: 0000000000000103
> [ 316.386056] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: 0000000000000001
> [ 316.386056] RBP: ffff88007fb63e60 R08: ffff88007fb6e140 R09: 0000000000000010
> [ 316.386056] R10: 0000000000000226 R11: 000000000000001f R12: 00000000cf0bff9b
> [ 316.386056] R13: 0000000000000001 R14: 00000000cfc06af0 R15: 0000000000000000
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] ffff88007fb63e60 ffffffff81339448 ffff88007fb6cc00 00000000cf0bff9b
> [ 316.386056] 0000000000000001 00000000cfc06af0 ffff88007fb63e70 ffffffff8133930a
> [ 316.386056] ffff88007fb63ea0 ffffffff810930c7 ffff88007fb6cc00 ffffffff81e080c8
> [ 316.386056] Call Trace:
> [ 316.386056] <IRQ> d [<ffffffff81339448>] ? delay_tsc+0x18/0xc0
> [ 316.386056] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 316.386056] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 316.386056] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 316.386056] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 316.386056] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 316.386056] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 316.386056] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 316.386056] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 316.386056] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 316.386056] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 316.386056] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 316.386056] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 316.386056] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 316.386056] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 316.386056] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 316.386056] [<ffffffff8114587f>] ? __mod_zone_page_state+0x6f/0xa0
> [ 316.386056] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 316.386056] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 316.386056] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 316.386056] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 316.386056] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 316.386056] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 316.386056] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 316.386056] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 316.386056] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 316.386056] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 316.386056] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 316.386056] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 316.386056] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 316.386056] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 316.386056] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 316.386056] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 316.386056] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 316.386056] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: c7 c7 fb dd c9 81 e8 72 f1 fd ff c6 05 a0 b3 e9 00 01 eb 9a 66 0f 1f 84 00 00 00 00 00 8b 15 02 a7 01 01 55 65 01 3d d2 2c f9 7e <48> 89 e5 53 89 fb 85 d2 75 11 65 8b 05 c1 2c f9 7e 0f b6 c0 3d
> [ 316.386056] NMI backtrace for cpu 12
> [ 316.386056] CPU: 12 PID: 786 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c91cb00 ti: ffff88007c0dc000 task.ti: ffff88007c0dc000
> [ 316.386056] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 316.386056] RSP: 0018:ffff88007c0dfc90 EFLAGS: 00000046
> [ 316.386056] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 000000000000000c
> [ 316.386056] RDX: 000000000000000c RSI: 0000000000000010 RDI: 0000000000000300
> [ 316.386056] RBP: ffff88007c0dfcc8 R08: 0000000000000000 R09: 000000000000f9ad
> [ 316.386056] R10: ffff88007c0dff58 R11: 00000000000005d1 R12: ffffffff81f31740
> [ 316.386056] R13: 0000000000000400 R14: 0000000000000002 R15: 000000000000000c
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] 0000000000000086 0000000c7c0dfca0 000000000000ff40 0000000000000001
> [ 316.386056] ffffffff8103fd20 00000000cfc06af0 ffff88007c0dfdd0 ffff88007c0dfcd8
> [ 316.386056] ffffffff8103fd36 ffff88007c0dfd20 ffffffff81331299 ffffffff81008b50
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 316.386056] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 316.386056] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 316.386056] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 316.386056] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 316.386056] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 316.386056] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 316.386056] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 316.386056] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 316.386056] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 316.386056] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 316.386056] NMI backtrace for cpu 13
> [ 316.386056] CPU: 13 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c918000 ti: ffff88007c0f4000 task.ti: ffff88007c0f4000
> [ 316.386056] RIP: 0010:[<ffffffff810addac>] [<ffffffff810addac>] rcu_read_delay+0x5c/0xb0
> [ 316.386056] RSP: 0018:ffff88007c0f7df0 EFLAGS: 00000202
> [ 316.386056] RAX: 000000000008efd6 RBX: 0000000000000000 RCX: 0000000000001770
> [ 316.386056] RDX: 000000000000032c RSI: ffff88007fbb27d8 RDI: ffff88007c0f7e20
> [ 316.386056] RBP: ffff88007c0f7e00 R08: ffff88007c0f4000 R09: ffff88007fbacc00
> [ 316.386056] R10: ffff88007c0f7e30 R11: 0000000000000001 R12: ffff88007c0f7e20
> [ 316.386056] R13: 00000069ba9c967b R14: 000000000000127b R15: ffffffff820d6fd0
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fba0000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] 0000000000000000 0000000000000000 ffff88007c0f7ea8 ffffffff810ad458
> [ 316.386056] 0000000000000000 0000000081a0a240 8723d0f72accd175 0000000000000c44
> [ 316.386056] 0000000000000000 ffff88007fbad1b8 00000001000258ae ffffffff810ad590
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: e8 8a b5 28 00 48 83 eb 01 75 f0 4c 89 e7 e8 6c 83 07 00 48 63 15 d9 94 02 01 48 8d 14 92 48 8d 0c 92 31 d2 48 c1 e1 04 48 f7 f1 <48> 85 d2 74 3c 65 8b 05 d8 cf f5 7e a9 ff ff ff 7f 74 05 5b 41
> [ 316.386056] NMI backtrace for cpu 14
> [ 316.386056] CPU: 14 PID: 783 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007c91a580 ti: ffff88007cb28000 task.ti: ffff88007cb28000
> [ 316.386056] RIP: 0010:[<ffffffff81339463>] [<ffffffff81339463>] delay_tsc+0x33/0xc0
> [ 316.386056] RSP: 0018:ffff88007cb2bdb0 EFLAGS: 00000286
> [ 316.386056] RAX: 0000000080000000 RBX: 0000016f89278228 RCX: 0000000000000001
> [ 316.386056] RDX: 0000000080000001 RSI: ffffffff81ca0d44 RDI: 00000000ffffffff
> [ 316.386056] RBP: ffff88007cb2bdd0 R08: ffff88007cb28000 R09: ffff88007fbccc00
> [ 316.386056] R10: ffff88007cb2be30 R11: 0000000000000001 R12: 0000016f88f62d58
> [ 316.386056] R13: 0000000000352ddb R14: 000000000000000e R15: ffffffff820d6fd0
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] 0000000000000005 ffff88007cb2be20 00000069b54181d9 000000000000127b
> [ 316.386056] ffff88007cb2bde0 ffffffff81339337 ffff88007cb2be00 ffffffff810add86
> [ 316.386056] 0000000000000000 0000000000000000 ffff88007cb2bea8 ffffffff810ad458
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 316.386056] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 316.386056] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 316.386056] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.386056] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.386056] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.386056] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.386056] Code: 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 <bf> 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f
> [ 316.386056] NMI backtrace for cpu 15
> [ 316.386056] CPU: 15 PID: 0 Comm: swapper/15 Tainted: G D 4.5.0-rc1+ #14
> [ 316.386056] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.386056] task: ffff88007cc9cb00 ti: ffff88007ccb8000 task.ti: ffff88007ccb8000
> [ 316.386056] RIP: 0010:[<ffffffff8100f303>] [<ffffffff8100f303>] default_idle+0x13/0xd0
> [ 316.386056] RSP: 0018:ffff88007ccbbec0 EFLAGS: 00000202
> [ 316.386056] RAX: 000000000000000f RBX: ffff88007ccbc000 RCX: 0000000000000000
> [ 316.386056] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 316.386056] RBP: ffff88007ccbbed0 R08: 0000000000000000 R09: 0000000000000000
> [ 316.386056] R10: 0000000000000010 R11: 0000000000018f70 R12: 0000000000000000
> [ 316.386056] R13: 0000000000000000 R14: ffff88007ccb8000 R15: ffff88007ccb8000
> [ 316.386056] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 316.386056] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.386056] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.386056] Stack:
> [ 316.386056] ffff88007ccbc000 0000000000000000 ffff88007ccbbee0 ffffffff8100fafa
> [ 316.386056] ffff88007ccbbef0 ffffffff8108fd65 ffff88007ccbbf30 ffffffff8108fff7
> [ 316.386056] ffff88007ccbc000 000000000000000f 0000000000000000 0000000000000000
> [ 316.386056] Call Trace:
> [ 316.386056] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 316.386056] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 316.386056] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 316.386056] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 316.386056] Code: 0f 1f 84 00 00 00 00 00 55 89 ff 48 89 e5 f0 48 0f ab 3e 5d c3 0f 1f 00 55 48 89 e5 41 54 53 e8 c4 8d 33 00 66 66 66 66 90 fb f4 <e8> b8 8d 33 00 41 89 c4 66 66 66 66 90 5b 41 5c 5d c3 41 89 c4
> [ 331.295005] BUG: spinlock lockup suspected on CPU#11, torture_onoff/798
> [ 331.295005] lock: 0xffff88007fb6cc00, .magic: dead4ead, .owner: torture_onoff/798, .owner_cpu: 11
> [ 331.295005] CPU: 11 PID: 798 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] ffff88007fb6cc00 ffff88007fb63e50 ffffffff8132cd6c ffff88007cafcb00
> [ 331.295005] ffff88007fb63e70 ffffffff81092fb3 ffff88007fb6cc00 00000000cfc06af0
> [ 331.295005] ffff88007fb63ea0 ffffffff810930db ffff88007fb6cc00 ffffffff81e080c8
> [ 331.295005] Call Trace:
> [ 331.295005] <IRQ> [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 331.295005] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 331.295005] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 331.295005] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 331.295005] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 331.295005] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 331.295005] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 331.295005] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 331.295005] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 331.295005] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 331.295005] <EOI> [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 331.295005] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 331.295005] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 331.295005] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 331.295005] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 331.295005] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 331.295005] [<ffffffff8114587f>] ? __mod_zone_page_state+0x6f/0xa0
> [ 331.295005] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 331.295005] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 331.295005] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 331.295005] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 331.295005] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 331.295005] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 331.295005] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 331.295005] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 331.295005] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 331.295005] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 331.295005] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 331.295005] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 331.295005] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 331.295005] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 331.295005] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 331.295005] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 331.295005] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 331.295005] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Sending NMI to all CPUs:
> [ 331.295005] NMI backtrace for cpu 0
> [ 331.295005] CPU: 0 PID: 784 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c91b200 ti: ffff88007cb2c000 task.ti: ffff88007cb2c000
> [ 331.295005] RIP: 0010:[<ffffffff81077f65>] [<ffffffff81077f65>] preempt_count_sub+0x15/0xa0
> [ 331.295005] RSP: 0018:ffff88007cb2fe00 EFLAGS: 00000246
> [ 331.295005] RAX: 000000000000000a RBX: 0000000000000000 RCX: 0000000000000000
> [ 331.295005] RDX: 0000000080000001 RSI: ffffffff81d29759 RDI: 0000000000000001
> [ 331.295005] RBP: ffff88007cb2fe00 R08: ffff88007cb2c000 R09: ffff88007fa0cc00
> [ 331.295005] R10: ffff88007cb2fe30 R11: 0000000000000001 R12: 0000000000000000
> [ 331.295005] R13: 00000069dd5e61b2 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506239dcc8 CR3: 000000007b0ee000 CR4: 00000000000006f0
> [ 331.295005] Stack:
> [ 331.295005] ffff88007cb2fea8 ffffffff810ad3a5 0000000000000000 0000000081a0a240
> [ 331.295005] 3c3b1143cab6927b 0000000000001d6d 0000000000000000 ffff88007fa0d3f8
> [ 331.295005] 0000000100025af6 ffffffff810ad590 0000000000000000 ffffffff00000000
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff810ad3a5>] rcu_torture_reader+0xf5/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: 08 b8 ea ff ff ff 5b 5d c3 48 83 c4 08 31 c0 5b 5d c3 0f 1f 40 00 8b 0d 62 a8 01 01 55 48 89 e5 85 c9 75 1b 65 8b 15 2b 2e f9 7e <89> d1 81 e1 ff ff ff 7f 39 cf 7f 13 81 ff fe 00 00 00 76 3f f7
> [ 331.295005] NMI backtrace for cpu 2
> [ 331.295005] CPU: 2 PID: 794 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007cafd780 ti: ffff88007c744000 task.ti: ffff88007c744000
> [ 331.295005] RIP: 0010:[<ffffffff810add72>] [<ffffffff810add72>] rcu_read_delay+0x22/0xb0
> [ 331.295005] RSP: 0018:ffff88007c747df0 EFLAGS: 00000246
> [ 331.295005] RAX: 0000000000000773 RBX: 0000000000000000 RCX: 000000000016e360
> [ 331.295005] RDX: 0000000000044071 RSI: ffff88007fa527d8 RDI: ffff88007c747e20
> [ 331.295005] RBP: ffff88007c747e00 R08: ffff88007c744000 R09: ffff88007fa4cc00
> [ 331.295005] R10: ffff88007c747e30 R11: 000000000000003c R12: ffff88007c747e20
> [ 331.295005] R13: 00000069dd5e7519 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] 0000000000000000 0000000000000000 ffff88007c747ea8 ffffffff810ad458
> [ 331.295005] 0000000000000000 000000007fa15380 d57caa470491aa84 0000000000001e98
> [ 331.295005] 0000000000000000 ffff88007fa4d3f8 0000000100025af6 ffffffff810ad590
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: ff ff 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 49 89 fc e8 a1 83 07 00 48 63 0d 0e 95 02 01 31 d2 48 69 c9 a0 86 01 00 48 f7 f1 <48> 85 d2 75 15 bb 32 00 00 00 bf 58 89 41 00 e8 8a b5 28 00 48
> [ 331.295005] NMI backtrace for cpu 3
> [ 331.295005] CPU: 3 PID: 782 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c919900 ti: ffff88007c5bc000 task.ti: ffff88007c5bc000
> [ 331.295005] RIP: 0010:[<ffffffff81347fe0>] [<ffffffff81347fe0>] check_preemption_disabled+0x0/0xe0
> [ 331.295005] RSP: 0018:ffff88007c5bfce8 EFLAGS: 00000097
> [ 331.295005] RAX: 0000000000000002 RBX: ffff88007fb6cc00 RCX: 0000000000000002
> [ 331.295005] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 331.295005] RBP: ffff88007c5bfcf0 R08: ffffffff81a0a240 R09: ffff88007fb6cc00
> [ 331.295005] R10: ffff88007c5bfe30 R11: 0000000000000400 R12: 00000000cc13eda5
> [ 331.295005] R13: 0000000000000001 R14: 00000000cfc06af0 R15: ffff88007c5bfdd0
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fa60000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] ffffffff813480d7 ffff88007c5bfd20 ffffffff8133944d ffff88007fb6cc00
> [ 331.295005] 00000000cc13eda5 0000000000000001 00000000cfc06af0 ffff88007c5bfd30
> [ 331.295005] ffffffff8133930a ffff88007c5bfd60 ffffffff810930c7 0000000000000286
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 331.295005] [<ffffffff8133944d>] delay_tsc+0x1d/0xc0
> [ 331.295005] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 331.295005] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 331.295005] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 331.295005] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 331.295005] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 331.295005] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 331.295005] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: 00 00 00 00 49 89 f7 c7 40 08 00 00 00 00 e9 1b ff ff ff 4d 89 e7 4c 8b 6d c8 49 83 cf 01 e9 0b ff ff ff 0f 1f 84 00 00 00 00 00 <55> 65 8b 05 a8 2d cc 7e 48 89 e5 41 56 41 55 41 54 53 65 8b 1d
> [ 331.295005] NMI backtrace for cpu 5
> [ 331.295005] CPU: 5 PID: 775 Comm: rcu_torture_wri Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c758000 ti: ffff88007c98c000 task.ti: ffff88007c98c000
> [ 331.295005] RIP: 0010:[<ffffffff810cd5c3>] [<ffffffff810cd5c3>] smp_call_function_single+0x103/0x140
> [ 331.295005] RSP: 0018:ffff88007c98fd50 EFLAGS: 00000202
> [ 331.295005] RAX: 0000000000000001 RBX: 0000000000000009 RCX: 0000000000000000
> [ 331.295005] RDX: 0000000000000000 RSI: ffff88007fab6440 RDI: ffffffff81cbdfe7
> [ 331.295005] RBP: ffff88007c98fd90 R08: ffffffff81a0a320 R09: 0000000000000002
> [ 331.295005] R10: 0000000000000009 R11: 0000000000000c00 R12: ffffffff810af980
> [ 331.295005] R13: ffffffff81e47ac0 R14: 0000000000016440 R15: ffffffff81e48e00
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007faa0000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] 0000000000000000 0000000000000000 0000000000000000 0000000000000003
> [ 331.295005] 000000000000cbb0 0000000000000002 0000000000000000 ffffffff81e47ac0
> [ 331.295005] ffff88007c98fde8 ffffffff810aedbe ffffffff810af980 0000000000000009
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff810aedbe>] sync_rcu_exp_select_cpus+0x1be/0x3d0
> [ 331.295005] [<ffffffff810af980>] ? rcu_seq_end.part.52+0x30/0x30
> [ 331.295005] [<ffffffff810afb9f>] synchronize_rcu_expedited.part.65+0x5f/0xb0
> [ 331.295005] [<ffffffff810afc06>] synchronize_rcu_expedited+0x16/0x40
> [ 331.295005] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 331.295005] [<ffffffff813394bf>] ? delay_tsc+0x8f/0xc0
> [ 331.295005] [<ffffffff81339366>] ? __udelay+0x26/0x30
> [ 331.295005] [<ffffffff810ac5a1>] rcu_torture_writer+0x441/0x6b0
> [ 331.295005] [<ffffffff810ac160>] ? rcu_torture_fakewriter+0x160/0x160
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: c6 05 f9 5e e4 00 01 eb 86 e8 1a ab 27 00 89 c0 49 c7 c6 40 64 01 00 4c 89 f6 48 03 34 c5 20 f5 f2 81 8b 46 18 a8 01 74 09 f3 90 <8b> 46 18 a8 01 75 f7 83 4e 18 01 89 df 4c 89 e9 4c 89 e2 e8 e5
> [ 331.295005] NMI backtrace for cpu 7
> [ 331.295005] CPU: 7 PID: 787 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c91d780 ti: ffff88007c750000 task.ti: ffff88007c750000
> [ 331.295005] RIP: 0010:[<ffffffff81347fe8>] [<ffffffff81347fe8>] check_preemption_disabled+0x8/0xe0
> [ 331.295005] RSP: 0018:ffff88007c753d90 EFLAGS: 00000246
> [ 331.295005] RAX: 0000000080000001 RBX: 0000017001a4f518 RCX: 0000000000000001
> [ 331.295005] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 331.295005] RBP: ffff88007c753da0 R08: ffff88007c750000 R09: ffff88007faecc00
> [ 331.295005] R10: ffff88007c753e30 R11: 0000000000000001 R12: 00000170019e5d88
> [ 331.295005] R13: 0000000000352fc5 R14: 0000000000000007 R15: ffffffff820d6fd0
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] ffff88007c753da0 ffffffff813480d7 ffff88007c753dd0 ffffffff81339472
> [ 331.295005] 000000000000000c ffff88007c753e20 00000069db15b06d 000000000000127b
> [ 331.295005] ffff88007c753de0 ffffffff81339337 ffff88007c753e00 ffffffff810add86
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 331.295005] [<ffffffff81339472>] delay_tsc+0x42/0xc0
> [ 331.295005] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 331.295005] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 331.295005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: 40 08 00 00 00 00 e9 1b ff ff ff 4d 89 e7 4c 8b 6d c8 49 83 cf 01 e9 0b ff ff ff 0f 1f 84 00 00 00 00 00 55 65 8b 05 a8 2d cc 7e <48> 89 e5 41 56 41 55 41 54 53 65 8b 1d 27 21 cc 7e a9 ff ff ff
> [ 331.295005] NMI backtrace for cpu 8
> [ 331.295005] CPU: 8 PID: 789 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c91f080 ti: ffff88007c0f0000 task.ti: ffff88007c0f0000
> [ 331.295005] RIP: 0010:[<ffffffff810930b9>] [<ffffffff810930b9>] do_raw_spin_lock+0x79/0x150
> [ 331.295005] RSP: 0018:ffff88007fb03db8 EFLAGS: 00000002
> [ 331.295005] RAX: 0000000000000001 RBX: ffff88007fb6cc00 RCX: 0000000000000103
> [ 331.295005] RDX: 0000000080000103 RSI: ffffffff81ca0d44 RDI: 00000000ffffffff
> [ 331.295005] RBP: ffff88007fb03dd8 R08: 0000000000000000 R09: 000000000000f9ad
> [ 331.295005] R10: 000000003d550944 R11: 0000000002faf04c R12: 00000000c7b4e675
> [ 331.295005] R13: 0000000000000001 R14: 00000000cfc06af0 R15: 0000000000000000
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fb00000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] ffff88007fb6cc00 ffffffff820d8c80 ffff88007fb6cc00 0000000000000000
> [ 331.295005] ffff88007fb03df0 ffffffff818b3fda 000000000000000b ffff88007fb03e30
> [ 331.295005] ffffffff810b96b6 0000000000000286 ffffffff81e4e828 000000fc640b0d4c
> [ 331.295005] Call Trace:
> [ 331.295005] <IRQ> d [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 331.295005] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 331.295005] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 331.295005] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 331.295005] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 331.295005] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 331.295005] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 331.295005] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 331.295005] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 331.295005] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 331.295005] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 331.295005] <EOI> d [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 331.295005] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 331.295005] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: c0 74 67 4c 69 35 b4 0f d8 00 e8 03 00 00 45 31 e4 41 bd 01 00 00 00 4d 85 f6 74 22 8b 03 85 c0 75 09 f0 44 0f b1 2b 85 c0 74 3f <bf> 01 00 00 00 49 83 c4 01 e8 39 62 2a 00 4d 39 e6 75 de 48 c7
> [ 331.295005] NMI backtrace for cpu 11
> [ 331.295005] CPU: 11 PID: 798 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
> [ 331.295005] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 331.295005] RSP: 0018:ffff88007fb63dd0 EFLAGS: 00000046
> [ 331.295005] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 000000000000000b
> [ 331.295005] RDX: 000000000000000b RSI: 0000000000000010 RDI: 0000000000000300
> [ 331.295005] RBP: ffff88007fb63e08 R08: 0000000000000000 R09: 000000000000f9ad
> [ 331.295005] R10: ffff88007c6f7f58 R11: 0000000000000773 R12: ffffffff81f31740
> [ 331.295005] R13: 0000000000000400 R14: 0000000000000002 R15: 000000000000000b
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] 0000000000000082 0000000b7fb63de0 000000000000ff40 0000000000000001
> [ 331.295005] ffffffff8103fd20 00000000cfc06af0 0000000000000000 ffff88007fb63e18
> [ 331.295005] ffffffff8103fd36 ffff88007fb63e60 ffffffff81331299 ffffffff81008b50
> [ 331.295005] Call Trace:
> [ 331.295005] <IRQ> d [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 331.295005] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 331.295005] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 331.295005] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 331.295005] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 331.295005] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 331.295005] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 331.295005] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 331.295005] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 331.295005] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 331.295005] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 331.295005] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 331.295005] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 331.295005] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 331.295005] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 331.295005] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 331.295005] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 331.295005] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 331.295005] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 331.295005] [<ffffffff8114587f>] ? __mod_zone_page_state+0x6f/0xa0
> [ 331.295005] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 331.295005] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 331.295005] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 331.295005] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 331.295005] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 331.295005] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 331.295005] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 331.295005] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 331.295005] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 331.295005] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 331.295005] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 331.295005] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 331.295005] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 331.295005] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 331.295005] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 331.295005] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 331.295005] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 331.295005] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 331.295005] NMI backtrace for cpu 12
> [ 331.295005] CPU: 12 PID: 786 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c91cb00 ti: ffff88007c0dc000 task.ti: ffff88007c0dc000
> [ 331.295005] RIP: 0010:[<ffffffff810920af>] [<ffffffff810920af>] queued_spin_lock_slowpath+0x16f/0x1a0
> [ 331.295005] RSP: 0018:ffff88007c0dfd18 EFLAGS: 00000002
> [ 331.295005] RAX: 0000000000000101 RBX: ffff88007fa2cc00 RCX: 0000000000000001
> [ 331.295005] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 331.295005] RBP: ffff88007c0dfd30 R08: 000000000000062f R09: 0000000000000743
> [ 331.295005] R10: ffff88007c0dff58 R11: 0000000000000743 R12: 00000000cfc06af0
> [ 331.295005] R13: 0000000000000001 R14: 00000000cfc06af0 R15: ffff88007c0dfdd0
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] ffff88007fa2cc00 00000000cfc06af0 0000000000000001 ffff88007c0dfd60
> [ 331.295005] ffffffff81093185 0000000000000286 ffff88007fa2cc00 ffff88007fa2cc00
> [ 331.295005] 000000000000cc00 ffff88007c0dfd80 ffffffff818b401f 0000000000000001
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 331.295005] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 331.295005] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 331.295005] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 331.295005] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 331.295005] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: c2 89 d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 <8b> 03 84 c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3
> [ 331.295005] NMI backtrace for cpu 13
> [ 331.295005] CPU: 13 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c918000 ti: ffff88007c0f4000 task.ti: ffff88007c0f4000
> [ 331.295005] RIP: 0010:[<ffffffff810780be>] [<ffffffff810780be>] preempt_count_add+0xe/0xc0
> [ 331.295005] RSP: 0018:ffff88007c0f7da0 EFLAGS: 00000282
> [ 331.295005] RAX: 0000000080000000 RBX: 0000017001aa6260 RCX: 0000000000000001
> [ 331.295005] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: 0000000000000001
> [ 331.295005] RBP: ffff88007c0f7dd0 R08: ffff88007c0f4000 R09: ffff88007fbacc00
> [ 331.295005] R10: ffff88007c0f7e30 R11: 0000000000000001 R12: 0000017001a4d5c0
> [ 331.295005] R13: 00000000000aa2c1 R14: 000000000000000d R15: ffffffff820d6fd0
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fba0000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] ffff88007c0f7dd0 ffffffff8133946d 0000000000000000 ffff88007c0f7e20
> [ 331.295005] 00000069dd5ea44f 000000000000127b ffff88007c0f7de0 ffffffff81339337
> [ 331.295005] ffff88007c0f7e00 ffffffff810addf7 0000000000000000 0000000000000000
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff8133946d>] ? delay_tsc+0x3d/0xc0
> [ 331.295005] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 331.295005] [<ffffffff810addf7>] rcu_read_delay+0xa7/0xb0
> [ 331.295005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: c7 c7 fb dd c9 81 e8 72 f1 fd ff c6 05 a0 b3 e9 00 01 eb 9a 66 0f 1f 84 00 00 00 00 00 8b 15 02 a7 01 01 55 65 01 3d d2 2c f9 7e <48> 89 e5 53 89 fb 85 d2 75 11 65 8b 05 c1 2c f9 7e 0f b6 c0 3d
> [ 331.295005] NMI backtrace for cpu 14
> [ 331.295005] CPU: 14 PID: 783 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007c91a580 ti: ffff88007cb28000 task.ti: ffff88007cb28000
> [ 331.295005] RIP: 0010:[<ffffffff81077f83>] [<ffffffff81077f83>] preempt_count_sub+0x33/0xa0
> [ 331.295005] RSP: 0018:ffff88007cb2be08 EFLAGS: 00000297
> [ 331.295005] RAX: 000000000000000a RBX: 0000000000000000 RCX: 0000000000000001
> [ 331.295005] RDX: 0000000080000001 RSI: ffffffff81d29759 RDI: 00000000ffffffff
> [ 331.295005] RBP: ffff88007cb2bea8 R08: ffff88007cb28000 R09: ffff88007fbccc00
> [ 331.295005] R10: ffff88007cb2be30 R11: 0000000000000001 R12: 0000000000000000
> [ 331.295005] R13: 00000069dd60520e R14: 000000000000127b R15: ffffffff820d6fd0
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] ffffffff810ad3a5 0000000000000000 0000000000015380 9abda0ee3aa4a492
> [ 331.295005] 0000000000001b28 0000000000000000 ffff88007fbcd3f8 0000000100025af6
> [ 331.295005] ffffffff810ad590 0000000000000000 ffffffff0000000e 00000000ffffffff
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff810ad3a5>] ? rcu_torture_reader+0xf5/0x2e0
> [ 331.295005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 331.295005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 331.295005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 331.295005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 331.295005] Code: 89 e5 85 c9 75 1b 65 8b 15 2b 2e f9 7e 89 d1 81 e1 ff ff ff 7f 39 cf 7f 13 81 ff fe 00 00 00 76 3f f7 df 65 01 3d 0e 2e f9 7e 5d <c3> e8 b7 34 2c 00 85 c0 74 f5 8b 15 0d 09 0a 01 85 d2 75 eb 48
> [ 331.295005] NMI backtrace for cpu 15
> [ 331.295005] CPU: 15 PID: 0 Comm: swapper/15 Tainted: G D 4.5.0-rc1+ #14
> [ 331.295005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 331.295005] task: ffff88007cc9cb00 ti: ffff88007ccb8000 task.ti: ffff88007ccb8000
> [ 331.295005] RIP: 0010:[<ffffffff8100f303>] [<ffffffff8100f303>] default_idle+0x13/0xd0
> [ 331.295005] RSP: 0018:ffff88007ccbbec0 EFLAGS: 00000202
> [ 331.295005] RAX: 000000000000000f RBX: ffff88007ccbc000 RCX: 0000000000000000
> [ 331.295005] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 331.295005] RBP: ffff88007ccbbed0 R08: 0000000000000000 R09: 0000000000000000
> [ 331.295005] R10: 0000000000000010 R11: 0000000000018f70 R12: 0000000000000000
> [ 331.295005] R13: 0000000000000000 R14: ffff88007ccb8000 R15: ffff88007ccb8000
> [ 331.295005] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 331.295005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 331.295005] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 331.295005] Stack:
> [ 331.295005] ffff88007ccbc000 0000000000000000 ffff88007ccbbee0 ffffffff8100fafa
> [ 331.295005] ffff88007ccbbef0 ffffffff8108fd65 ffff88007ccbbf30 ffffffff8108fff7
> [ 331.295005] ffff88007ccbc000 000000000000000f 0000000000000000 0000000000000000
> [ 331.295005] Call Trace:
> [ 331.295005] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 331.295005] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 331.295005] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 331.295005] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 331.295005] Code: 0f 1f 84 00 00 00 00 00 55 89 ff 48 89 e5 f0 48 0f ab 3e 5d c3 0f 1f 00 55 48 89 e5 41 54 53 e8 c4 8d 33 00 66 66 66 66 90 fb f4 <e8> b8 8d 33 00 41 89 c4 66 66 66 66 90 5b 41 5c 5d c3 41 89 c4
> [ 316.338053] BUG: spinlock lockup suspected on CPU#3, rcu_torture_rea/782
> [ 316.338053] lock: 0xffff88007fb6cc00, .magic: dead4ead, .owner: torture_onoff/798, .owner_cpu: 11
> [ 316.338053] CPU: 3 PID: 782 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] ffff88007fb6cc00 ffff88007c5bfd10 ffffffff8132cd6c ffff88007cafcb00
> [ 316.338053] ffff88007c5bfd30 ffffffff81092fb3 ffff88007fb6cc00 00000000cfc06af0
> [ 316.338053] ffff88007c5bfd60 ffffffff810930db 0000000000000286 ffff88007fb6cc00
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 316.338053] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 316.338053] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 316.338053] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 316.338053] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 316.338053] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 316.338053] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 316.338053] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Sending NMI to all CPUs:
> [ 316.338053] NMI backtrace for cpu 0
> [ 316.338053] CPU: 0 PID: 780 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c75be80 ti: ffff88007c774000 task.ti: ffff88007c774000
> [ 316.338053] RIP: 0010:[<ffffffff818af940>] [<ffffffff818af940>] _cond_resched+0x0/0x20
> [ 316.338053] RSP: 0018:ffff88007c777df0 EFLAGS: 00000202
> [ 316.338053] RAX: 0000000000000001 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 316.338053] RDX: 0000000080000000 RSI: 0000000000000286 RDI: ffffffff81c9f0eb
> [ 316.338053] RBP: ffff88007c777e00 R08: ffff88007c774000 R09: ffff88007fa0cc00
> [ 316.338053] R10: ffff88007c777e30 R11: 000000000000005a R12: 0000000000000000
> [ 316.338053] R13: 0000006a519a813f R14: 000000000000127b R15: ffffffff820d6fd0
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506239dcc8 CR3: 000000007b0ee000 CR4: 00000000000006f0
> [ 316.338053] Stack:
> [ 316.338053] ffffffff81126479 0000000000000000 ffff88007c777ea8 ffffffff810ad3ce
> [ 316.338053] 0000000000000000 0000000081a0a240 44bdc3e2f3607f45 0000000000001066
> [ 316.338053] dead000000000200 0000000000000000 0000000100026293 ffffffff810ad590
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 316.338053] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 75 7e a9 ff ff ff 7f 74 01 c3 9c 58 f6 c4 02 74 f8 55 48 89 e5 e8 a1 ff ff ff 5d c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 <65> 8b 15 49 b4 75 7e 85 d2 74 03 31 c0 c3 55 48 89 e5 e8 79 ff
> [ 316.338053] NMI backtrace for cpu 2
> [ 316.338053] CPU: 2 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c918000 ti: ffff88007c0f4000 task.ti: ffff88007c0f4000
> [ 316.338053] RIP: 0010:[<ffffffff81126474>] [<ffffffff81126474>] stutter_wait+0x44/0xc0
> [ 316.338053] RSP: 0018:ffff88007c0f7df8 EFLAGS: 00000202
> [ 316.338053] RAX: 0000000000000001 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 316.338053] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 316.338053] RBP: ffff88007c0f7e00 R08: ffff88007c0f4000 R09: ffff88007fa4cc00
> [ 316.338053] R10: ffff88007c0f7e30 R11: 000000000000005a R12: 0000000000000000
> [ 316.338053] R13: 0000006a51d7a937 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] 0000000000000000 ffff88007c0f7ea8 ffffffff810ad3ce 0000000000000000
> [ 316.338053] 0000000081a0a240 e1c9c2832fdf50b8 00000000000010f6 dead000000000200
> [ 316.338053] 0000000000000000 0000000100026298 ffffffff810ad590 0000000000000000
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 75 12 48 8b 05 0e af fd 00 48 85 c0 74 66 8b 00 85 c0 75 60 8b 05 61 ae fd 00 85 c0 74 26 8b 05 57 ae fd 00 83 f8 01 75 07 eb 35 <e8> c7 94 78 00 8b 05 45 ae fd 00 85 c0 75 f1 48 89 df e8 65 ff
> [ 316.338053] NMI backtrace for cpu 3
> [ 316.338053] CPU: 3 PID: 782 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c919900 ti: ffff88007c5bc000 task.ti: ffff88007c5bc000
> [ 316.338053] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 316.338053] RSP: 0018:ffff88007c5bfc90 EFLAGS: 00000046
> [ 316.338053] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 0000000000000003
> [ 316.338053] RDX: 0000000000000003 RSI: 0000000000000010 RDI: 0000000000000300
> [ 316.338053] RBP: ffff88007c5bfcc8 R08: 0000000000000000 R09: 000000000000f9ad
> [ 316.338053] R10: ffff88007c5bff58 R11: 00000000000008fa R12: ffffffff81f31740
> [ 316.338053] R13: 0000000000000400 R14: 0000000000000002 R15: 0000000000000003
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fa60000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] 0000000000000086 000000037c5bfca0 000000000000ff40 0000000000000001
> [ 316.338053] ffffffff8103fd20 00000000cfc06af0 ffff88007c5bfdd0 ffff88007c5bfcd8
> [ 316.338053] ffffffff8103fd36 ffff88007c5bfd20 ffffffff81331299 ffffffff81008b50
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 316.338053] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 316.338053] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 316.338053] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 316.338053] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 316.338053] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 316.338053] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 316.338053] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 316.338053] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 316.338053] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 316.338053] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 316.338053] NMI backtrace for cpu 5
> [ 316.338053] CPU: 5 PID: 775 Comm: rcu_torture_wri Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c758000 ti: ffff88007c98c000 task.ti: ffff88007c98c000
> [ 316.338053] RIP: 0010:[<ffffffff810cd5c6>] [<ffffffff810cd5c6>] smp_call_function_single+0x106/0x140
> [ 316.338053] RSP: 0018:ffff88007c98fd50 EFLAGS: 00000202
> [ 316.338053] RAX: 0000000000000001 RBX: 0000000000000009 RCX: 0000000000000000
> [ 316.338053] RDX: 0000000000000000 RSI: ffff88007fab6440 RDI: ffffffff81cbdfe7
> [ 316.338053] RBP: ffff88007c98fd90 R08: ffffffff81a0a320 R09: 0000000000000002
> [ 316.338053] R10: 0000000000000009 R11: 0000000000000c00 R12: ffffffff810af980
> [ 316.338053] R13: ffffffff81e47ac0 R14: 0000000000016440 R15: ffffffff81e48e00
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007faa0000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] 0000000000000000 0000000000000000 0000000000000000 0000000000000003
> [ 316.338053] 000000000000cbb0 0000000000000002 0000000000000000 ffffffff81e47ac0
> [ 316.338053] ffff88007c98fde8 ffffffff810aedbe ffffffff810af980 0000000000000009
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff810aedbe>] sync_rcu_exp_select_cpus+0x1be/0x3d0
> [ 316.338053] [<ffffffff810af980>] ? rcu_seq_end.part.52+0x30/0x30
> [ 316.338053] [<ffffffff810afb9f>] synchronize_rcu_expedited.part.65+0x5f/0xb0
> [ 316.338053] [<ffffffff810afc06>] synchronize_rcu_expedited+0x16/0x40
> [ 316.338053] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 316.338053] [<ffffffff813394bf>] ? delay_tsc+0x8f/0xc0
> [ 316.338053] [<ffffffff81339366>] ? __udelay+0x26/0x30
> [ 316.338053] [<ffffffff810ac5a1>] rcu_torture_writer+0x441/0x6b0
> [ 316.338053] [<ffffffff810ac160>] ? rcu_torture_fakewriter+0x160/0x160
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 5e e4 00 01 eb 86 e8 1a ab 27 00 89 c0 49 c7 c6 40 64 01 00 4c 89 f6 48 03 34 c5 20 f5 f2 81 8b 46 18 a8 01 74 09 f3 90 8b 46 18 <a8> 01 75 f7 83 4e 18 01 89 df 4c 89 e9 4c 89 e2 e8 e5 fd ff ff
> [ 316.338053] NMI backtrace for cpu 7
> [ 316.338053] CPU: 7 PID: 783 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c91a580 ti: ffff88007cb28000 task.ti: ffff88007cb28000
> [ 316.338053] RIP: 0010:[<ffffffff81126479>] [<ffffffff81126479>] stutter_wait+0x49/0xc0
> [ 316.338053] RSP: 0018:ffff88007cb2bdf8 EFLAGS: 00000246
> [ 316.338053] RAX: 0000000000000000 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 316.338053] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 316.338053] RBP: ffff88007cb2be00 R08: ffff88007cb28000 R09: ffff88007faecc00
> [ 316.338053] R10: ffff88007cb2be30 R11: 0000000000000001 R12: 0000000000000000
> [ 316.338053] R13: 0000006a51d7a959 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] 0000000000000000 ffff88007cb2bea8 ffffffff810ad3ce 0000000000000000
> [ 316.338053] 0000000000015380 938d1d05a9edd694 00000000000000f6 dead000000000200
> [ 316.338053] 0000000000000000 0000000100026298 ffffffff810ad590 0000000000000000
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 0e af fd 00 48 85 c0 74 66 8b 00 85 c0 75 60 8b 05 61 ae fd 00 85 c0 74 26 8b 05 57 ae fd 00 83 f8 01 75 07 eb 35 e8 c7 94 78 00 <8b> 05 45 ae fd 00 85 c0 75 f1 48 89 df e8 65 ff ff ff eb b4 bf
> [ 316.338053] NMI backtrace for cpu 8
> [ 316.338053] CPU: 8 PID: 789 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c91f080 ti: ffff88007c0f0000 task.ti: ffff88007c0f0000
> [ 316.338053] RIP: 0010:[<ffffffff81339455>] [<ffffffff81339455>] delay_tsc+0x25/0xc0
> [ 316.338053] RSP: 0018:ffff88007fb03d78 EFLAGS: 00000006
> [ 316.338053] RAX: 0000000032ed229e RBX: ffff88007fb6cc00 RCX: 0000000000000103
> [ 316.338053] RDX: 0000000000000172 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 316.338053] RBP: ffff88007fb03d98 R08: 0000000000000000 R09: 000000000000f9ad
> [ 316.338053] R10: 000000003d550944 R11: 0000000002faf04c R12: 00000000cb2cbf89
> [ 316.338053] R13: 0000000000000001 R14: 0000000000000008 R15: 0000000000000000
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fb00000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] ffff88007fb6cc00 00000000cb2cbf89 0000000000000001 00000000cfc06af0
> [ 316.338053] ffff88007fb03da8 ffffffff8133930a ffff88007fb03dd8 ffffffff810930c7
> [ 316.338053] ffff88007fb6cc00 ffffffff820d8c80 ffff88007fb6cc00 0000000000000000
> [ 316.338053] Call Trace:
> [ 316.338053] <IRQ> d [<ffffffff8133930a>] __delay+0xa/0x10
> [ 316.338053] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 316.338053] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 316.338053] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 316.338053] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 316.338053] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 316.338053] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 316.338053] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 316.338053] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 316.338053] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 316.338053] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 316.338053] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 316.338053] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 316.338053] <EOI> d [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 316.338053] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 316.338053] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 5e 41 5f 5d c3 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 <48> c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 43
> [ 316.338053] NMI backtrace for cpu 11
> [ 316.338053] CPU: 11 PID: 798 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
> [ 316.338053] RIP: 0010:[<ffffffff810920b1>] [<ffffffff810920b1>] queued_spin_lock_slowpath+0x171/0x1a0
> [ 316.338053] RSP: 0018:ffff88007fb63e58 EFLAGS: 00000002
> [ 316.338053] RAX: 0000000000000101 RBX: ffff88007fb6cc00 RCX: 0000000000000001
> [ 316.338053] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 316.338053] RBP: ffff88007fb63e70 R08: 000000000000062f R09: 00000000000008e3
> [ 316.338053] R10: ffff88007c6f7f58 R11: 00000000000008e3 R12: 00000000cfc06af0
> [ 316.338053] R13: 0000000000000001 R14: 00000000cfc06af0 R15: 0000000000000000
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] ffff88007fb6cc00 00000000cfc06af0 0000000000000001 ffff88007fb63ea0
> [ 316.338053] ffffffff81093185 ffff88007fb6cc00 ffffffff81e080c8 0000000000000001
> [ 316.338053] 0000000000000001 ffff88007fb63eb8 ffffffff818b3ffb ffff88007fb6cc00
> [ 316.338053] Call Trace:
> [ 316.338053] <IRQ> d [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 316.338053] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 316.338053] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 316.338053] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 316.338053] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 316.338053] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 316.338053] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 316.338053] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 316.338053] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 316.338053] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 316.338053] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 316.338053] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 316.338053] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 316.338053] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 316.338053] [<ffffffff8114587f>] ? __mod_zone_page_state+0x6f/0xa0
> [ 316.338053] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 316.338053] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 316.338053] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 316.338053] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 316.338053] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 316.338053] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 316.338053] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 316.338053] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 316.338053] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 316.338053] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 316.338053] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 316.338053] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 316.338053] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 316.338053] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 316.338053] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 316.338053] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 316.338053] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 316.338053] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 8b 03 <84> c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3 f3 90
> [ 316.338053] NMI backtrace for cpu 12
> [ 316.338053] CPU: 12 PID: 786 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c91cb00 ti: ffff88007c0dc000 task.ti: ffff88007c0dc000
> [ 316.338053] RIP: 0010:[<ffffffff810920af>] [<ffffffff810920af>] queued_spin_lock_slowpath+0x16f/0x1a0
> [ 316.338053] RSP: 0018:ffff88007c0dfd18 EFLAGS: 00000002
> [ 316.338053] RAX: 0000000000000101 RBX: ffff88007fa2cc00 RCX: 0000000000000001
> [ 316.338053] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 316.338053] RBP: ffff88007c0dfd30 R08: 000000000000062f R09: 0000000000000743
> [ 316.338053] R10: ffff88007c0dff58 R11: 0000000000000743 R12: 00000000cfc06af0
> [ 316.338053] R13: 0000000000000001 R14: 00000000cfc06af0 R15: ffff88007c0dfdd0
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] ffff88007fa2cc00 00000000cfc06af0 0000000000000001 ffff88007c0dfd60
> [ 316.338053] ffffffff81093185 0000000000000286 ffff88007fa2cc00 ffff88007fa2cc00
> [ 316.338053] 000000000000cc00 ffff88007c0dfd80 ffffffff818b401f 0000000000000001
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 316.338053] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 316.338053] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 316.338053] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 316.338053] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 316.338053] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: c2 89 d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 <8b> 03 84 c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3
> [ 316.338053] NMI backtrace for cpu 13
> [ 316.338053] CPU: 13 PID: 793 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007caf8c80 ti: ffff88007c740000 task.ti: ffff88007c740000
> [ 316.338053] RIP: 0010:[<ffffffff81126479>] [<ffffffff81126479>] stutter_wait+0x49/0xc0
> [ 316.338053] RSP: 0018:ffff88007c743df8 EFLAGS: 00000246
> [ 316.338053] RAX: 0000000000000000 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 316.338053] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 316.338053] RBP: ffff88007c743e00 R08: ffff88007c740000 R09: ffff88007fbacc00
> [ 316.338053] R10: ffff88007c743e30 R11: 0000000000000001 R12: 0000000000000000
> [ 316.338053] R13: 0000006a51d78b8c R14: 000000000000127b R15: ffffffff820d6fd0
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fba0000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] 0000000000000000 ffff88007c743ea8 ffffffff810ad3ce 0000000000000000
> [ 316.338053] 0000000081a0a240 9db61e92c238bec5 00000000000000a4 dead000000000200
> [ 316.338053] 0000000000000000 0000000100026297 ffffffff810ad590 0000000000000000
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 0e af fd 00 48 85 c0 74 66 8b 00 85 c0 75 60 8b 05 61 ae fd 00 85 c0 74 26 8b 05 57 ae fd 00 83 f8 01 75 07 eb 35 e8 c7 94 78 00 <8b> 05 45 ae fd 00 85 c0 75 f1 48 89 df e8 65 ff ff ff eb b4 bf
> [ 316.338053] NMI backtrace for cpu 14
> [ 316.338053] CPU: 14 PID: 781 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007c918c80 ti: ffff88007c5b8000 task.ti: ffff88007c5b8000
> [ 316.338053] RIP: 0010:[<ffffffff818af940>] [<ffffffff818af940>] _cond_resched+0x0/0x20
> [ 316.338053] RSP: 0018:ffff88007c5bbdf0 EFLAGS: 00000202
> [ 316.338053] RAX: 0000000000000001 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 316.338053] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 316.338053] RBP: ffff88007c5bbe00 R08: ffff88007c5b8000 R09: ffff88007fbccc00
> [ 316.338053] R10: ffff88007c5bbe30 R11: 0000000000000001 R12: 0000000000000000
> [ 316.338053] R13: 0000006a51d78bd7 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] ffffffff81126479 0000000000000000 ffff88007c5bbea8 ffffffff810ad3ce
> [ 316.338053] 0000000000000000 0000000081a0a240 1f40bd867ce4d9c3 0000000000000d0d
> [ 316.338053] dead000000000200 0000000000000000 0000000100026297 ffffffff810ad590
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 316.338053] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 316.338053] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 316.338053] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 316.338053] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 316.338053] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 316.338053] Code: 75 7e a9 ff ff ff 7f 74 01 c3 9c 58 f6 c4 02 74 f8 55 48 89 e5 e8 a1 ff ff ff 5d c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 <65> 8b 15 49 b4 75 7e 85 d2 74 03 31 c0 c3 55 48 89 e5 e8 79 ff
> [ 316.338053] NMI backtrace for cpu 15
> [ 316.338053] CPU: 15 PID: 0 Comm: swapper/15 Tainted: G D 4.5.0-rc1+ #14
> [ 316.338053] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 316.338053] task: ffff88007cc9cb00 ti: ffff88007ccb8000 task.ti: ffff88007ccb8000
> [ 316.338053] RIP: 0010:[<ffffffff8100f303>] [<ffffffff8100f303>] default_idle+0x13/0xd0
> [ 316.338053] RSP: 0018:ffff88007ccbbec0 EFLAGS: 00000202
> [ 316.338053] RAX: 000000000000000f RBX: ffff88007ccbc000 RCX: 0000000000000000
> [ 316.338053] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 316.338053] RBP: ffff88007ccbbed0 R08: 0000000000000000 R09: 0000000000000000
> [ 316.338053] R10: 0000000000000010 R11: 0000000000018f70 R12: 0000000000000000
> [ 316.338053] R13: 0000000000000000 R14: ffff88007ccb8000 R15: ffff88007ccb8000
> [ 316.338053] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 316.338053] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 316.338053] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 316.338053] Stack:
> [ 316.338053] ffff88007ccbc000 0000000000000000 ffff88007ccbbee0 ffffffff8100fafa
> [ 316.338053] ffff88007ccbbef0 ffffffff8108fd65 ffff88007ccbbf30 ffffffff8108fff7
> [ 316.338053] ffff88007ccbc000 000000000000000f 0000000000000000 0000000000000000
> [ 316.338053] Call Trace:
> [ 316.338053] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 316.338053] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 316.338053] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 316.338053] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 316.338053] Code: 0f 1f 84 00 00 00 00 00 55 89 ff 48 89 e5 f0 48 0f ab 3e 5d c3 0f 1f 00 55 48 89 e5 41 54 53 e8 c4 8d 33 00 66 66 66 66 90 fb f4 <e8> b8 8d 33 00 41 89 c4 66 66 66 66 90 5b 41 5c 5d c3 41 89 c4
> [ 311.122004] BUG: spinlock lockup suspected on CPU#8, rcu_torture_rea/789
> [ 311.122004] lock: 0xffff88007fb6cc00, .magic: dead4ead, .owner: torture_onoff/798, .owner_cpu: 11
> [ 311.122004] CPU: 8 PID: 789 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] ffff88007fb6cc00 ffff88007fb03d88 ffffffff8132cd6c ffff88007cafcb00
> [ 311.122004] ffff88007fb03da8 ffffffff81092fb3 ffff88007fb6cc00 00000000cfc06af0
> [ 311.122004] ffff88007fb03dd8 ffffffff810930db ffff88007fb6cc00 ffffffff820d8c80
> [ 311.122004] Call Trace:
> [ 311.122004] <IRQ> [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 311.122004] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 311.122004] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 311.122004] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 311.122004] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 311.122004] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 311.122004] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 311.122004] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 311.122004] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 311.122004] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 311.122004] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 311.122004] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 311.122004] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 311.122004] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 311.122004] <EOI> [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 311.122004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 311.122004] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Sending NMI to all CPUs:
> [ 311.122004] NMI backtrace for cpu 0
> [ 311.122004] CPU: 0 PID: 780 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c75be80 ti: ffff88007c774000 task.ti: ffff88007c774000
> [ 311.122004] RIP: 0010:[<ffffffff818af94b>] [<ffffffff818af94b>] _cond_resched+0xb/0x20
> [ 311.122004] RSP: 0018:ffff88007c777df0 EFLAGS: 00000286
> [ 311.122004] RAX: 0000000000000001 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 311.122004] RDX: 0000000080000000 RSI: 0000000000000286 RDI: ffffffff81c9f0eb
> [ 311.122004] RBP: ffff88007c777e00 R08: ffff88007c774000 R09: ffff88007fa0cc00
> [ 311.122004] R10: ffff88007c777e30 R11: 000000000000005a R12: 0000000000000000
> [ 311.122004] R13: 0000006a519a813f R14: 000000000000127b R15: ffffffff820d6fd0
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506239dcc8 CR3: 000000007b0ee000 CR4: 00000000000006f0
> [ 311.122004] Stack:
> [ 311.122004] ffffffff81126479 0000000000000000 ffff88007c777ea8 ffffffff810ad3ce
> [ 311.122004] 0000000000000000 0000000081a0a240 44bdc3e2f3607f45 0000000000001066
> [ 311.122004] dead000000000200 0000000000000000 0000000100026293 ffffffff810ad590
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 311.122004] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: 58 f6 c4 02 74 f8 55 48 89 e5 e8 a1 ff ff ff 5d c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 65 8b 15 49 b4 75 7e 85 d2 74 03 <31> c0 c3 55 48 89 e5 e8 79 ff ff ff b8 01 00 00 00 5d c3 66 90
> [ 311.122004] NMI backtrace for cpu 2
> [ 311.122004] CPU: 2 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c918000 ti: ffff88007c0f4000 task.ti: ffff88007c0f4000
> [ 311.122004] RIP: 0010:[<ffffffff81126479>] [<ffffffff81126479>] stutter_wait+0x49/0xc0
> [ 311.122004] RSP: 0018:ffff88007c0f7df8 EFLAGS: 00000246
> [ 311.122004] RAX: 0000000000000000 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 311.122004] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 311.122004] RBP: ffff88007c0f7e00 R08: ffff88007c0f4000 R09: ffff88007fa4cc00
> [ 311.122004] R10: ffff88007c0f7e30 R11: 000000000000005a R12: 0000000000000000
> [ 311.122004] R13: 0000006a51d7a937 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] 0000000000000000 ffff88007c0f7ea8 ffffffff810ad3ce 0000000000000000
> [ 311.122004] 0000000081a0a240 e1c9c2832fdf50b8 00000000000010f6 dead000000000200
> [ 311.122004] 0000000000000000 0000000100026298 ffffffff810ad590 0000000000000000
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: 0e af fd 00 48 85 c0 74 66 8b 00 85 c0 75 60 8b 05 61 ae fd 00 85 c0 74 26 8b 05 57 ae fd 00 83 f8 01 75 07 eb 35 e8 c7 94 78 00 <8b> 05 45 ae fd 00 85 c0 75 f1 48 89 df e8 65 ff ff ff eb b4 bf
> [ 311.122004] NMI backtrace for cpu 3
> [ 311.122004] CPU: 3 PID: 782 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c919900 ti: ffff88007c5bc000 task.ti: ffff88007c5bc000
> [ 311.122004] RIP: 0010:[<ffffffff81092067>] [<ffffffff81092067>] queued_spin_lock_slowpath+0x127/0x1a0
> [ 311.122004] RSP: 0018:ffff88007c5bfd18 EFLAGS: 00000002
> [ 311.122004] RAX: 0000000000000000 RBX: ffff88007fb6cc00 RCX: ffff88007fa75e80
> [ 311.122004] RDX: 0000000000100101 RSI: ffffffff81ca0d44 RDI: 0000000000100000
> [ 311.122004] RBP: ffff88007c5bfd30 R08: 0000000000000000 R09: 0000000000000a64
> [ 311.122004] R10: ffff88007c5bff58 R11: 0000000000000a64 R12: 0000000000000000
> [ 311.122004] R13: ffff88007fa75e80 R14: 00000000cfc06af0 R15: ffff88007c5bfdd0
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fa60000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] ffff88007fb6cc00 00000000cfc06af0 0000000000000001 ffff88007c5bfd60
> [ 311.122004] ffffffff81093185 0000000000000286 ffff88007fb6cc00 ffff88007fb6cc00
> [ 311.122004] 000000000000cc00 ffff88007c5bfd80 ffffffff818b401f 000000000000000b
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 311.122004] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 311.122004] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 311.122004] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 311.122004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 311.122004] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: 48 03 14 c5 20 f5 f2 81 48 89 0a 8b 41 08 85 c0 75 09 f3 90 8b 41 08 85 c0 74 f7 4c 8b 01 4d 85 c0 74 08 41 0f 18 08 eb 02 f3 90 <8b> 13 66 85 d2 75 f7 be 01 00 00 00 eb 10 89 d0 f0 0f b1 33 39
> [ 311.122004] NMI backtrace for cpu 5
> [ 311.122004] CPU: 5 PID: 775 Comm: rcu_torture_wri Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c758000 ti: ffff88007c98c000 task.ti: ffff88007c98c000
> [ 311.122004] RIP: 0010:[<ffffffff810cd5c3>] [<ffffffff810cd5c3>] smp_call_function_single+0x103/0x140
> [ 311.122004] RSP: 0018:ffff88007c98fd50 EFLAGS: 00000202
> [ 311.122004] RAX: 0000000000000001 RBX: 0000000000000009 RCX: 0000000000000000
> [ 311.122004] RDX: 0000000000000000 RSI: ffff88007fab6440 RDI: ffffffff81cbdfe7
> [ 311.122004] RBP: ffff88007c98fd90 R08: ffffffff81a0a320 R09: 0000000000000002
> [ 311.122004] R10: 0000000000000009 R11: 0000000000000c00 R12: ffffffff810af980
> [ 311.122004] R13: ffffffff81e47ac0 R14: 0000000000016440 R15: ffffffff81e48e00
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007faa0000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] 0000000000000000 0000000000000000 0000000000000000 0000000000000003
> [ 311.122004] 000000000000cbb0 0000000000000002 0000000000000000 ffffffff81e47ac0
> [ 311.122004] ffff88007c98fde8 ffffffff810aedbe ffffffff810af980 0000000000000009
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff810aedbe>] sync_rcu_exp_select_cpus+0x1be/0x3d0
> [ 311.122004] [<ffffffff810af980>] ? rcu_seq_end.part.52+0x30/0x30
> [ 311.122004] [<ffffffff810afb9f>] synchronize_rcu_expedited.part.65+0x5f/0xb0
> [ 311.122004] [<ffffffff810afc06>] synchronize_rcu_expedited+0x16/0x40
> [ 311.122004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 311.122004] [<ffffffff813394bf>] ? delay_tsc+0x8f/0xc0
> [ 311.122004] [<ffffffff81339366>] ? __udelay+0x26/0x30
> [ 311.122004] [<ffffffff810ac5a1>] rcu_torture_writer+0x441/0x6b0
> [ 311.122004] [<ffffffff810ac160>] ? rcu_torture_fakewriter+0x160/0x160
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: c6 05 f9 5e e4 00 01 eb 86 e8 1a ab 27 00 89 c0 49 c7 c6 40 64 01 00 4c 89 f6 48 03 34 c5 20 f5 f2 81 8b 46 18 a8 01 74 09 f3 90 <8b> 46 18 a8 01 75 f7 83 4e 18 01 89 df 4c 89 e9 4c 89 e2 e8 e5
> [ 311.122004] NMI backtrace for cpu 7
> [ 311.122004] CPU: 7 PID: 783 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c91a580 ti: ffff88007cb28000 task.ti: ffff88007cb28000
> [ 311.122004] RIP: 0010:[<ffffffff81126479>] [<ffffffff81126479>] stutter_wait+0x49/0xc0
> [ 311.122004] RSP: 0018:ffff88007cb2bdf8 EFLAGS: 00000246
> [ 311.122004] RAX: 0000000000000000 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 311.122004] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 311.122004] RBP: ffff88007cb2be00 R08: ffff88007cb28000 R09: ffff88007faecc00
> [ 311.122004] R10: ffff88007cb2be30 R11: 0000000000000001 R12: 0000000000000000
> [ 311.122004] R13: 0000006a51d7a959 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] 0000000000000000 ffff88007cb2bea8 ffffffff810ad3ce 0000000000000000
> [ 311.122004] 0000000000015380 938d1d05a9edd694 00000000000000f6 dead000000000200
> [ 311.122004] 0000000000000000 0000000100026298 ffffffff810ad590 0000000000000000
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: 0e af fd 00 48 85 c0 74 66 8b 00 85 c0 75 60 8b 05 61 ae fd 00 85 c0 74 26 8b 05 57 ae fd 00 83 f8 01 75 07 eb 35 e8 c7 94 78 00 <8b> 05 45 ae fd 00 85 c0 75 f1 48 89 df e8 65 ff ff ff eb b4 bf
> [ 311.122004] NMI backtrace for cpu 8
> [ 311.122004] CPU: 8 PID: 789 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c91f080 ti: ffff88007c0f0000 task.ti: ffff88007c0f0000
> [ 311.122004] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 311.122004] RSP: 0018:ffff88007fb03d08 EFLAGS: 00000046
> [ 311.122004] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 0000000000000008
> [ 311.122004] RDX: 0000000000000008 RSI: 0000000000000010 RDI: 0000000000000300
> [ 311.122004] RBP: ffff88007fb03d40 R08: 0000000000000000 R09: 000000000000f9ad
> [ 311.122004] R10: ffff88007c0f3f58 R11: 0000000000000a84 R12: ffffffff81f31740
> [ 311.122004] R13: 0000000000000400 R14: 0000000000000002 R15: 0000000000000008
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fb00000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] 0000000000000082 000000087fb03d18 000000000000ff40 0000000000000001
> [ 311.122004] ffffffff8103fd20 00000000cfc06af0 0000000000000000 ffff88007fb03d50
> [ 311.122004] ffffffff8103fd36 ffff88007fb03d98 ffffffff81331299 ffffffff81008b50
> [ 311.122004] Call Trace:
> [ 311.122004] <IRQ> d [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 311.122004] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 311.122004] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 311.122004] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 311.122004] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 311.122004] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 311.122004] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 311.122004] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 311.122004] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 311.122004] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 311.122004] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 311.122004] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 311.122004] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 311.122004] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 311.122004] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 311.122004] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 311.122004] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 311.122004] <EOI> d [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 311.122004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 311.122004] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 311.122004] NMI backtrace for cpu 11
> [ 311.122004] CPU: 11 PID: 798 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
> [ 311.122004] RIP: 0010:[<ffffffff810920af>] [<ffffffff810920af>] queued_spin_lock_slowpath+0x16f/0x1a0
> [ 311.122004] RSP: 0018:ffff88007fb63e58 EFLAGS: 00000002
> [ 311.122004] RAX: 0000000000100101 RBX: ffff88007fb6cc00 RCX: 0000000000000001
> [ 311.122004] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 311.122004] RBP: ffff88007fb63e70 R08: 000000000000062f R09: 00000000000008e3
> [ 311.122004] R10: ffff88007c6f7f58 R11: 00000000000008e3 R12: 00000000cfc06af0
> [ 311.122004] R13: 0000000000000001 R14: 00000000cfc06af0 R15: 0000000000000000
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] ffff88007fb6cc00 00000000cfc06af0 0000000000000001 ffff88007fb63ea0
> [ 311.122004] ffffffff81093185 ffff88007fb6cc00 ffffffff81e080c8 0000000000000001
> [ 311.122004] 0000000000000001 ffff88007fb63eb8 ffffffff818b3ffb ffff88007fb6cc00
> [ 311.122004] Call Trace:
> [ 311.122004] <IRQ> d [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 311.122004] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 311.122004] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 311.122004] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 311.122004] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 311.122004] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 311.122004] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 311.122004] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 311.122004] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 311.122004] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 311.122004] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 311.122004] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 311.122004] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 311.122004] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 311.122004] [<ffffffff8114587f>] ? __mod_zone_page_state+0x6f/0xa0
> [ 311.122004] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 311.122004] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 311.122004] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 311.122004] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 311.122004] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 311.122004] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 311.122004] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 311.122004] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 311.122004] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 311.122004] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 311.122004] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 311.122004] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 311.122004] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 311.122004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 311.122004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 311.122004] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 311.122004] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 311.122004] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: c2 89 d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 <8b> 03 84 c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3
> [ 311.122004] NMI backtrace for cpu 12
> [ 311.122004] CPU: 12 PID: 786 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c91cb00 ti: ffff88007c0dc000 task.ti: ffff88007c0dc000
> [ 311.122004] RIP: 0010:[<ffffffff810920af>] [<ffffffff810920af>] queued_spin_lock_slowpath+0x16f/0x1a0
> [ 311.122004] RSP: 0018:ffff88007c0dfd18 EFLAGS: 00000002
> [ 311.122004] RAX: 0000000000000101 RBX: ffff88007fa2cc00 RCX: 0000000000000001
> [ 311.122004] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 311.122004] RBP: ffff88007c0dfd30 R08: 000000000000062f R09: 0000000000000743
> [ 311.122004] R10: ffff88007c0dff58 R11: 0000000000000743 R12: 00000000cfc06af0
> [ 311.122004] R13: 0000000000000001 R14: 00000000cfc06af0 R15: ffff88007c0dfdd0
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] ffff88007fa2cc00 00000000cfc06af0 0000000000000001 ffff88007c0dfd60
> [ 311.122004] ffffffff81093185 0000000000000286 ffff88007fa2cc00 ffff88007fa2cc00
> [ 311.122004] 000000000000cc00 ffff88007c0dfd80 ffffffff818b401f 0000000000000001
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 311.122004] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 311.122004] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 311.122004] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 311.122004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 311.122004] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: c2 89 d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 <8b> 03 84 c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3
> [ 311.122004] NMI backtrace for cpu 13
> [ 311.122004] CPU: 13 PID: 793 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007caf8c80 ti: ffff88007c740000 task.ti: ffff88007c740000
> [ 311.122004] RIP: 0010:[<ffffffff818af940>] [<ffffffff818af940>] _cond_resched+0x0/0x20
> [ 311.122004] RSP: 0018:ffff88007c743df0 EFLAGS: 00000202
> [ 311.122004] RAX: 0000000000000001 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 311.122004] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 311.122004] RBP: ffff88007c743e00 R08: ffff88007c740000 R09: ffff88007fbacc00
> [ 311.122004] R10: ffff88007c743e30 R11: 0000000000000001 R12: 0000000000000000
> [ 311.122004] R13: 0000006a51d78b8c R14: 000000000000127b R15: ffffffff820d6fd0
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fba0000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] ffffffff81126479 0000000000000000 ffff88007c743ea8 ffffffff810ad3ce
> [ 311.122004] 0000000000000000 0000000081a0a240 9db61e92c238bec5 00000000000000a4
> [ 311.122004] dead000000000200 0000000000000000 0000000100026297 ffffffff810ad590
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 311.122004] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: 75 7e a9 ff ff ff 7f 74 01 c3 9c 58 f6 c4 02 74 f8 55 48 89 e5 e8 a1 ff ff ff 5d c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 <65> 8b 15 49 b4 75 7e 85 d2 74 03 31 c0 c3 55 48 89 e5 e8 79 ff
> [ 311.122004] NMI backtrace for cpu 14
> [ 311.122004] CPU: 14 PID: 781 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007c918c80 ti: ffff88007c5b8000 task.ti: ffff88007c5b8000
> [ 311.122004] RIP: 0010:[<ffffffff818af940>] [<ffffffff818af940>] _cond_resched+0x0/0x20
> [ 311.122004] RSP: 0018:ffff88007c5bbdf0 EFLAGS: 00000202
> [ 311.122004] RAX: 0000000000000001 RBX: ffffffff81c9f0eb RCX: 0000000000000001
> [ 311.122004] RDX: 0000000080000000 RSI: ffffffff81d29759 RDI: ffffffff81c9f0eb
> [ 311.122004] RBP: ffff88007c5bbe00 R08: ffff88007c5b8000 R09: ffff88007fbccc00
> [ 311.122004] R10: ffff88007c5bbe30 R11: 0000000000000001 R12: 0000000000000000
> [ 311.122004] R13: 0000006a51d78bd7 R14: 000000000000127b R15: ffffffff820d6fd0
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] ffffffff81126479 0000000000000000 ffff88007c5bbea8 ffffffff810ad3ce
> [ 311.122004] 0000000000000000 0000000081a0a240 1f40bd867ce4d9c3 0000000000000d0d
> [ 311.122004] dead000000000200 0000000000000000 0000000100026297 ffffffff810ad590
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 311.122004] [<ffffffff810ad3ce>] rcu_torture_reader+0x11e/0x2e0
> [ 311.122004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 311.122004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 311.122004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 311.122004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 311.122004] Code: 75 7e a9 ff ff ff 7f 74 01 c3 9c 58 f6 c4 02 74 f8 55 48 89 e5 e8 a1 ff ff ff 5d c3 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 <65> 8b 15 49 b4 75 7e 85 d2 74 03 31 c0 c3 55 48 89 e5 e8 79 ff
> [ 311.122004] NMI backtrace for cpu 15
> [ 311.122004] CPU: 15 PID: 0 Comm: swapper/15 Tainted: G D 4.5.0-rc1+ #14
> [ 311.122004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 311.122004] task: ffff88007cc9cb00 ti: ffff88007ccb8000 task.ti: ffff88007ccb8000
> [ 311.122004] RIP: 0010:[<ffffffff8100f303>] [<ffffffff8100f303>] default_idle+0x13/0xd0
> [ 311.122004] RSP: 0018:ffff88007ccbbec0 EFLAGS: 00000202
> [ 311.122004] RAX: 000000000000000f RBX: ffff88007ccbc000 RCX: 0000000000000000
> [ 311.122004] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 311.122004] RBP: ffff88007ccbbed0 R08: 0000000000000000 R09: 0000000000000000
> [ 311.122004] R10: 0000000000000010 R11: 0000000000018f70 R12: 0000000000000000
> [ 311.122004] R13: 0000000000000000 R14: ffff88007ccb8000 R15: ffff88007ccb8000
> [ 311.122004] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 311.122004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 311.122004] CR2: 000056506230a720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 311.122004] Stack:
> [ 311.122004] ffff88007ccbc000 0000000000000000 ffff88007ccbbee0 ffffffff8100fafa
> [ 311.122004] ffff88007ccbbef0 ffffffff8108fd65 ffff88007ccbbf30 ffffffff8108fff7
> [ 311.122004] ffff88007ccbc000 000000000000000f 0000000000000000 0000000000000000
> [ 311.122004] Call Trace:
> [ 311.122004] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 311.122004] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 311.122004] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 311.122004] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 311.122004] Code: 0f 1f 84 00 00 00 00 00 55 89 ff 48 89 e5 f0 48 0f ab 3e 5d c3 0f 1f 00 55 48 89 e5 41 54 53 e8 c4 8d 33 00 66 66 66 66 90 fb f4 <e8> b8 8d 33 00 41 89 c4 66 66 66 66 90 5b 41 5c 5d c3 41 89 c4
> [ 462.372004] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 462.372004] 3-...: (1 GPs behind) idle=6cf/140000000000000/0 softirq=8341/8345 fqs=48568
> [ 462.372004] 8-...: (1 GPs behind) idle=503/140000000000001/0 softirq=9290/9294 fqs=48568
> [ 462.372004] 11-...: (1 GPs behind) idle=32f/140000000000001/0 softirq=8320/8323 fqs=48568
> [ 462.372004] 12-...: (1 GPs behind) idle=e2f/140000000000000/0 softirq=8014/8017 fqs=48569
> [ 462.372004] (detected by 13, t=147016 jiffies, g=4731, c=4730, q=2)
> [ 462.372004] Task dump for CPU 3:
> [ 462.372004] rcu_torture_rea R running task 14064 782 2 0x00000008
> [ 462.372004] 0000000000000a63 ffff88007c5bff58 ffff88007fb6cc00 0000000000000000
> [ 462.372004] ffff88007fa75e80 00000000cfc06af0 ffff88007c5bfd08 ffffffff813480d7
> [ 462.372004] ffff88007c5bfd30 ffffffff81091faf ffff88007fb6cc00 00000000cfc06af0
> [ 462.372004] Call Trace:
> [ 462.372004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 462.372004] [<ffffffff81091faf>] ? queued_spin_lock_slowpath+0x6f/0x1a0
> [ 462.372004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 462.372004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 462.372004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 462.372004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 462.372004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 462.372004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 462.372004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 462.372004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 462.372004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 462.372004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 462.372004] Task dump for CPU 8:
> [ 462.372004] rcu_torture_rea R running task 14760 789 2 0x00000008
> [ 462.372004] ffffffff818af15c ffff88007c0f3ce8 ffff88007cdcbe80 ffff88007c91f080
> [ 462.372004] 0000000000000046 0000000000000000 ffff88007c0f4000 0000000000000000
> [ 462.372004] 00000047648a43ed 000000000000126f ffffffff820d6eb0 ffff88007c0f3d38
> [ 462.372004] Call Trace:
> [ 462.372004] [<ffffffff818af15c>] ? __schedule+0x38c/0xb00
> [ 462.372004] [<ffffffff818afd13>] ? preempt_schedule_irq+0x43/0x60
> [ 462.372004] [<ffffffff818b513b>] ? retint_kernel+0x1b/0x1d
> [ 462.372004] [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 462.372004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 462.372004] [<ffffffff810ad3ce>] ? rcu_torture_reader+0x11e/0x2e0
> [ 462.372004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 462.372004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 462.372004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 462.372004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 462.372004] Task dump for CPU 11:
> [ 462.372004] torture_onoff R running task 13416 798 2 0x00000008
> [ 462.372004] ffffffff8104a8b5 ffff88007ffdb600 ffff88007fb78f70 0000000000000002
> [ 462.372004] 0000000000000000 0000000000000000 ffff88007c6f7be8 ffff88007cafcb00
> [ 462.372004] ffff88007c6f7b70 ffffffff8104aa3e ffff88007c6f7bc8 ffffffff8104ac95
> [ 462.372004] Call Trace:
> [ 462.372004] [<ffffffff8104a8b5>] ? __bad_area_nosemaphore+0x75/0x1f0
> [ 462.372004] [<ffffffff8104aa3e>] ? bad_area_nosemaphore+0xe/0x10
> [ 462.372004] [<ffffffff8104ac95>] ? __do_page_fault+0x85/0x450
> [ 462.372004] [<ffffffff8104b06c>] ? do_page_fault+0xc/0x10
> [ 462.372004] [<ffffffff818b6422>] ? page_fault+0x22/0x30
> [ 462.372004] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 462.372004] [<ffffffff810b95c4>] ? timer_cpu_notify+0xe4/0x160
> [ 462.372004] [<ffffffff81073ea5>] ? notifier_call_chain+0x45/0x70
> [ 462.372004] [<ffffffff81073fc9>] ? __raw_notifier_call_chain+0x9/0x10
> [ 462.372004] [<ffffffff8105759e>] ? cpu_notify_nofail+0x1e/0x30
> [ 462.372004] [<ffffffff81057852>] ? _cpu_down+0x212/0x350
> [ 462.372004] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 462.372004] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 462.372004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 462.372004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 462.372004] [<ffffffff810579bf>] ? cpu_down+0x2f/0x50
> [ 462.372004] [<ffffffff811266b5>] ? torture_onoff+0x115/0x380
> [ 462.372004] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 462.372004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 462.372004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 462.372004] Task dump for CPU 12:
> [ 462.372004] rcu_torture_rea R running task 14064 786 2 0x00000008
> [ 462.372004] 0000000000000742 ffff88007c0dff58 ffff88007c0dfd20 ffffffff813311f5
> [ 462.372004] 000000000000062f 0000000f7fa2cc00 ffff88007fa2cc00 00000000cfc06af0
> [ 462.372004] 0000000000000001 00000000cfc06af0 ffff88007fa2cc00 00000000cfc06af0
> [ 462.372004] Call Trace:
> [ 462.372004] [<ffffffff813311f5>] ? nmi_trigger_all_cpu_backtrace+0x1b5/0x270
> [ 462.372004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 462.372004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 462.372004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 462.372004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 462.372004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 462.372004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 462.372004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 462.372004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 462.372004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 462.372004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 462.372004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 481.191011] rcu-torture: rtc: ffffffff820d6fd0 ver: 2590 tfle: 0 rta: 2591 rtaf: 0 rtf: 2581 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1388586 onoff: 128/128:132/133 34,3223:11,552 19099:13437 (HZ=1000) barrier: 0/0:0 cbflood: 608
> [ 481.193164] rcu-torture: Reader Pipe: 10501340394 14768 0 0 0 0 0 0 0 0 0
> [ 481.194038] rcu-torture: Reader Batch: 10185892351 315462811 0 0 0 0 0 0 0 0 0
> [ 481.194945] rcu-torture: Free-Block Circulation: 2590 2589 2588 2587 2586 2585 2584 2583 2582 2581 0
> [ 481.196067] ??? Writer stall state RTWS_EXP_SYNC(4) g4731 c4730 f0x0
> [ 481.196689] rcu_preempt: wait state: 3 ->state: 0x1
> [ 481.197181] rcu_sched: wait state: 1 ->state: 0x1
> [ 481.197658] rcu_bh: wait state: 1 ->state: 0x1
> [ 525.377004] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 525.377004] 3-...: (1 GPs behind) idle=6cf/140000000000000/0 softirq=8341/8345 fqs=69054
> [ 525.377004] 8-...: (1 GPs behind) idle=503/140000000000001/0 softirq=9290/9294 fqs=69054
> [ 525.377004] 11-...: (1 GPs behind) idle=32f/140000000000001/0 softirq=8320/8323 fqs=69054
> [ 525.377004] 12-...: (1 GPs behind) idle=e2f/140000000000000/0 softirq=8014/8017 fqs=69054
> [ 525.377004] (detected by 2, t=210021 jiffies, g=4731, c=4730, q=2)
> [ 525.377004] Task dump for CPU 3:
> [ 525.377004] rcu_torture_rea R running task 14064 782 2 0x00000008
> [ 525.377004] 0000000000000a63 ffff88007c5bff58 ffff88007fb6cc00 0000000000000000
> [ 525.377004] ffff88007fa75e80 00000000cfc06af0 ffff88007c5bfd08 ffffffff813480d7
> [ 525.377004] ffff88007c5bfd30 ffffffff81091faf ffff88007fb6cc00 00000000cfc06af0
> [ 525.377004] Call Trace:
> [ 525.377004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 525.377004] [<ffffffff81091faf>] ? queued_spin_lock_slowpath+0x6f/0x1a0
> [ 525.377004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 525.377004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 525.377004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 525.377004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 525.377004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 525.377004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 525.377004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 525.377004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 525.377004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 525.377004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 525.377004] Task dump for CPU 8:
> [ 525.377004] rcu_torture_rea R running task 14760 789 2 0x00000008
> [ 525.377004] ffffffff818af15c ffff88007c0f3ce8 ffff88007cdcbe80 ffff88007c91f080
> [ 525.377004] 0000000000000046 0000000000000000 ffff88007c0f4000 0000000000000000
> [ 525.377004] 00000047648a43ed 000000000000126f ffffffff820d6eb0 ffff88007c0f3d38
> [ 525.377004] Call Trace:
> [ 525.377004] [<ffffffff818af15c>] ? __schedule+0x38c/0xb00
> [ 525.377004] [<ffffffff818afd13>] ? preempt_schedule_irq+0x43/0x60
> [ 525.377004] [<ffffffff818b513b>] ? retint_kernel+0x1b/0x1d
> [ 525.377004] [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 525.377004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 525.377004] [<ffffffff810ad3ce>] ? rcu_torture_reader+0x11e/0x2e0
> [ 525.377004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 525.377004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 525.377004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 525.377004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 525.377004] Task dump for CPU 11:
> [ 525.377004] torture_onoff R running task 13416 798 2 0x00000008
> [ 525.377004] ffffffff8104a8b5 ffff88007ffdb600 ffff88007fb78f70 0000000000000002
> [ 525.377004] 0000000000000000 0000000000000000 ffff88007c6f7be8 ffff88007cafcb00
> [ 525.377004] ffff88007c6f7b70 ffffffff8104aa3e ffff88007c6f7bc8 ffffffff8104ac95
> [ 525.377004] Call Trace:
> [ 525.377004] [<ffffffff8104a8b5>] ? __bad_area_nosemaphore+0x75/0x1f0
> [ 525.377004] [<ffffffff8104aa3e>] ? bad_area_nosemaphore+0xe/0x10
> [ 525.377004] [<ffffffff8104ac95>] ? __do_page_fault+0x85/0x450
> [ 525.377004] [<ffffffff8104b06c>] ? do_page_fault+0xc/0x10
> [ 525.377004] [<ffffffff818b6422>] ? page_fault+0x22/0x30
> [ 525.377004] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 525.377004] [<ffffffff810b95c4>] ? timer_cpu_notify+0xe4/0x160
> [ 525.377004] [<ffffffff81073ea5>] ? notifier_call_chain+0x45/0x70
> [ 525.377004] [<ffffffff81073fc9>] ? __raw_notifier_call_chain+0x9/0x10
> [ 525.377004] [<ffffffff8105759e>] ? cpu_notify_nofail+0x1e/0x30
> [ 525.377004] [<ffffffff81057852>] ? _cpu_down+0x212/0x350
> [ 525.377004] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 525.377004] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 525.377004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 525.377004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 525.377004] [<ffffffff810579bf>] ? cpu_down+0x2f/0x50
> [ 525.377004] [<ffffffff811266b5>] ? torture_onoff+0x115/0x380
> [ 525.377004] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 525.377004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 525.377004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 525.377004] Task dump for CPU 12:
> [ 525.377004] rcu_torture_rea R running task 14064 786 2 0x00000008
> [ 525.377004] 0000000000000742 ffff88007c0dff58 ffff88007c0dfd20 ffffffff813311f5
> [ 525.377004] 000000000000062f 0000000f7fa2cc00 ffff88007fa2cc00 00000000cfc06af0
> [ 525.377004] 0000000000000001 00000000cfc06af0 ffff88007fa2cc00 00000000cfc06af0
> [ 525.377004] Call Trace:
> [ 525.377004] [<ffffffff813311f5>] ? nmi_trigger_all_cpu_backtrace+0x1b5/0x270
> [ 525.377004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 525.377004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 525.377004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 525.377004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 525.377004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 525.377004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 525.377004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 525.377004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 525.377004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 525.377004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 525.377004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 541.198012] rcu-torture: rtc: ffffffff820d6fd0 ver: 2590 tfle: 0 rta: 2591 rtaf: 0 rtf: 2581 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1507834 onoff: 128/128:132/133 34,3223:11,552 19099:13437 (HZ=1000) barrier: 0/0:0 cbflood: 608
> [ 541.200373] rcu-torture: Reader Pipe: 11417029944 14768 0 0 0 0 0 0 0 0 0
> [ 541.201326] rcu-torture: Reader Batch: 11101581901 315462811 0 0 0 0 0 0 0 0 0
> [ 541.202335] rcu-torture: Free-Block Circulation: 2590 2589 2588 2587 2586 2585 2584 2583 2582 2581 0
> [ 541.203542] ??? Writer stall state RTWS_EXP_SYNC(4) g4731 c4730 f0x0
> [ 541.204243] rcu_preempt: wait state: 3 ->state: 0x1
> [ 541.204777] rcu_sched: wait state: 1 ->state: 0x1
> [ 541.205309] rcu_bh: wait state: 1 ->state: 0x1
> [ 588.382004] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 588.382004] 3-...: (1 GPs behind) idle=6cf/140000000000000/0 softirq=8341/8345 fqs=90027
> [ 588.382004] 8-...: (1 GPs behind) idle=503/140000000000001/0 softirq=9290/9294 fqs=90027
> [ 588.382004] 11-...: (1 GPs behind) idle=32f/140000000000001/0 softirq=8320/8323 fqs=90027
> [ 588.382004] 12-...: (1 GPs behind) idle=e2f/140000000000000/0 softirq=8014/8017 fqs=90027
> [ 588.382004] (detected by 2, t=273026 jiffies, g=4731, c=4730, q=6)
> [ 588.382004] Task dump for CPU 3:
> [ 588.382004] rcu_torture_rea R running task 14064 782 2 0x00000008
> [ 588.382004] 0000000000000a63 ffff88007c5bff58 ffff88007fb6cc00 0000000000000000
> [ 588.382004] ffff88007fa75e80 00000000cfc06af0 ffff88007c5bfd08 ffffffff813480d7
> [ 588.382004] ffff88007c5bfd30 ffffffff81091faf ffff88007fb6cc00 00000000cfc06af0
> [ 588.382004] Call Trace:
> [ 588.382004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 588.382004] [<ffffffff81091faf>] ? queued_spin_lock_slowpath+0x6f/0x1a0
> [ 588.382004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 588.382004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 588.382004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 588.382004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 588.382004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 588.382004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 588.382004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 588.382004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 588.382004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 588.382004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 588.382004] Task dump for CPU 8:
> [ 588.382004] rcu_torture_rea R running task 14760 789 2 0x00000008
> [ 588.382004] ffffffff818af15c ffff88007c0f3ce8 ffff88007cdcbe80 ffff88007c91f080
> [ 588.382004] 0000000000000046 0000000000000000 ffff88007c0f4000 0000000000000000
> [ 588.382004] 00000047648a43ed 000000000000126f ffffffff820d6eb0 ffff88007c0f3d38
> [ 588.382004] Call Trace:
> [ 588.382004] [<ffffffff818af15c>] ? __schedule+0x38c/0xb00
> [ 588.382004] [<ffffffff818afd13>] ? preempt_schedule_irq+0x43/0x60
> [ 588.382004] [<ffffffff818b513b>] ? retint_kernel+0x1b/0x1d
> [ 588.382004] [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 588.382004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 588.382004] [<ffffffff810ad3ce>] ? rcu_torture_reader+0x11e/0x2e0
> [ 588.382004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 588.382004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 588.382004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 588.382004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 588.382004] Task dump for CPU 11:
> [ 588.382004] torture_onoff R running task 13416 798 2 0x00000008
> [ 588.382004] ffffffff8104a8b5 ffff88007ffdb600 ffff88007fb78f70 0000000000000002
> [ 588.382004] 0000000000000000 0000000000000000 ffff88007c6f7be8 ffff88007cafcb00
> [ 588.382004] ffff88007c6f7b70 ffffffff8104aa3e ffff88007c6f7bc8 ffffffff8104ac95
> [ 588.382004] Call Trace:
> [ 588.382004] [<ffffffff8104a8b5>] ? __bad_area_nosemaphore+0x75/0x1f0
> [ 588.382004] [<ffffffff8104aa3e>] ? bad_area_nosemaphore+0xe/0x10
> [ 588.382004] [<ffffffff8104ac95>] ? __do_page_fault+0x85/0x450
> [ 588.382004] [<ffffffff8104b06c>] ? do_page_fault+0xc/0x10
> [ 588.382004] [<ffffffff818b6422>] ? page_fault+0x22/0x30
> [ 588.382004] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 588.382004] [<ffffffff810b95c4>] ? timer_cpu_notify+0xe4/0x160
> [ 588.382004] [<ffffffff81073ea5>] ? notifier_call_chain+0x45/0x70
> [ 588.382004] [<ffffffff81073fc9>] ? __raw_notifier_call_chain+0x9/0x10
> [ 588.382004] [<ffffffff8105759e>] ? cpu_notify_nofail+0x1e/0x30
> [ 588.382004] [<ffffffff81057852>] ? _cpu_down+0x212/0x350
> [ 588.382004] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 588.382004] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 588.382004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 588.382004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 588.382004] [<ffffffff810579bf>] ? cpu_down+0x2f/0x50
> [ 588.382004] [<ffffffff811266b5>] ? torture_onoff+0x115/0x380
> [ 588.382004] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 588.382004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 588.382004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 588.382004] Task dump for CPU 12:
> [ 588.382004] rcu_torture_rea R running task 14064 786 2 0x00000008
> [ 588.382004] 0000000000000742 ffff88007c0dff58 ffff88007c0dfd20 ffffffff813311f5
> [ 588.382004] 000000000000062f 0000000f7fa2cc00 ffff88007fa2cc00 00000000cfc06af0
> [ 588.382004] 0000000000000001 00000000cfc06af0 ffff88007fa2cc00 00000000cfc06af0
> [ 588.382004] Call Trace:
> [ 588.382004] [<ffffffff813311f5>] ? nmi_trigger_all_cpu_backtrace+0x1b5/0x270
> [ 588.382004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 588.382004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 588.382004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 588.382004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 588.382004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 588.382004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 588.382004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 588.382004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 588.382004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 588.382004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 588.382004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 601.205012] rcu-torture: rtc: ffffffff820d6fd0 ver: 2590 tfle: 0 rta: 2591 rtaf: 0 rtf: 2581 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1628388 onoff: 128/128:132/133 34,3223:11,552 19099:13437 (HZ=1000) barrier: 0/0:0 cbflood: 608
> [ 601.207374] rcu-torture: Reader Pipe: 12328853039 14768 0 0 0 0 0 0 0 0 0
> [ 601.208335] rcu-torture: Reader Batch: 12013404996 315462811 0 0 0 0 0 0 0 0 0
> [ 601.209353] rcu-torture: Free-Block Circulation: 2590 2589 2588 2587 2586 2585 2584 2583 2582 2581 0
> [ 601.210556] ??? Writer stall state RTWS_EXP_SYNC(4) g4731 c4730 f0x0
> [ 601.211259] rcu_preempt: wait state: 3 ->state: 0x1
> [ 601.211796] rcu_sched: wait state: 1 ->state: 0x1
> [ 601.212335] rcu_bh: wait state: 1 ->state: 0x1
> [ 651.387004] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 651.387004] 3-...: (1 GPs behind) idle=6cf/140000000000000/0 softirq=8341/8345 fqs=111003
> [ 651.387004] 8-...: (1 GPs behind) idle=503/140000000000001/0 softirq=9290/9294 fqs=111003
> [ 651.387004] 11-...: (1 GPs behind) idle=32f/140000000000001/0 softirq=8320/8323 fqs=111004
> [ 651.387004] 12-...: (1 GPs behind) idle=e2f/140000000000000/0 softirq=8014/8017 fqs=111004
> [ 651.387004] (detected by 13, t=336031 jiffies, g=4731, c=4730, q=10)
> [ 651.387004] Task dump for CPU 3:
> [ 651.387004] rcu_torture_rea R running task 14064 782 2 0x00000008
> [ 651.387004] 0000000000000a63 ffff88007c5bff58 ffff88007fb6cc00 0000000000000000
> [ 651.387004] ffff88007fa75e80 00000000cfc06af0 ffff88007c5bfd08 ffffffff813480d7
> [ 651.387004] ffff88007c5bfd30 ffffffff81091faf ffff88007fb6cc00 00000000cfc06af0
> [ 651.387004] Call Trace:
> [ 651.387004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 651.387004] [<ffffffff81091faf>] ? queued_spin_lock_slowpath+0x6f/0x1a0
> [ 651.387004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 651.387004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 651.387004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 651.387004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 651.387004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 651.387004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 651.387004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 651.387004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 651.387004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 651.387004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 651.387004] Task dump for CPU 8:
> [ 651.387004] rcu_torture_rea R running task 14760 789 2 0x00000008
> [ 651.387004] ffffffff818af15c ffff88007c0f3ce8 ffff88007cdcbe80 ffff88007c91f080
> [ 651.387004] 0000000000000046 0000000000000000 ffff88007c0f4000 0000000000000000
> [ 651.387004] 00000047648a43ed 000000000000126f ffffffff820d6eb0 ffff88007c0f3d38
> [ 651.387004] Call Trace:
> [ 651.387004] [<ffffffff818af15c>] ? __schedule+0x38c/0xb00
> [ 651.387004] [<ffffffff818afd13>] ? preempt_schedule_irq+0x43/0x60
> [ 651.387004] [<ffffffff818b513b>] ? retint_kernel+0x1b/0x1d
> [ 651.387004] [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 651.387004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 651.387004] [<ffffffff810ad3ce>] ? rcu_torture_reader+0x11e/0x2e0
> [ 651.387004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 651.387004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 651.387004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 651.387004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 651.387004] Task dump for CPU 11:
> [ 651.387004] torture_onoff R running task 13416 798 2 0x00000008
> [ 651.387004] ffffffff8104a8b5 ffff88007ffdb600 ffff88007fb78f70 0000000000000002
> [ 651.387004] 0000000000000000 0000000000000000 ffff88007c6f7be8 ffff88007cafcb00
> [ 651.387004] ffff88007c6f7b70 ffffffff8104aa3e ffff88007c6f7bc8 ffffffff8104ac95
> [ 651.387004] Call Trace:
> [ 651.387004] [<ffffffff8104a8b5>] ? __bad_area_nosemaphore+0x75/0x1f0
> [ 651.387004] [<ffffffff8104aa3e>] ? bad_area_nosemaphore+0xe/0x10
> [ 651.387004] [<ffffffff8104ac95>] ? __do_page_fault+0x85/0x450
> [ 651.387004] [<ffffffff8104b06c>] ? do_page_fault+0xc/0x10
> [ 651.387004] [<ffffffff818b6422>] ? page_fault+0x22/0x30
> [ 651.387004] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 651.387004] [<ffffffff810b95c4>] ? timer_cpu_notify+0xe4/0x160
> [ 651.387004] [<ffffffff81073ea5>] ? notifier_call_chain+0x45/0x70
> [ 651.387004] [<ffffffff81073fc9>] ? __raw_notifier_call_chain+0x9/0x10
> [ 651.387004] [<ffffffff8105759e>] ? cpu_notify_nofail+0x1e/0x30
> [ 651.387004] [<ffffffff81057852>] ? _cpu_down+0x212/0x350
> [ 651.387004] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 651.387004] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 651.387004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 651.387004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 651.387004] [<ffffffff810579bf>] ? cpu_down+0x2f/0x50
> [ 651.387004] [<ffffffff811266b5>] ? torture_onoff+0x115/0x380
> [ 651.387004] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 651.387004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 651.387004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 651.387004] Task dump for CPU 12:
> [ 651.387004] rcu_torture_rea R running task 14064 786 2 0x00000008
> [ 651.387004] 0000000000000742 ffff88007c0dff58 ffff88007c0dfd20 ffffffff813311f5
> [ 651.387004] 000000000000062f 0000000f7fa2cc00 ffff88007fa2cc00 00000000cfc06af0
> [ 651.387004] 0000000000000001 00000000cfc06af0 ffff88007fa2cc00 00000000cfc06af0
> [ 651.387004] Call Trace:
> [ 651.387004] [<ffffffff813311f5>] ? nmi_trigger_all_cpu_backtrace+0x1b5/0x270
> [ 651.387004] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 651.387004] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 651.387004] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 651.387004] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 651.387004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 651.387004] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 651.387004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 651.387004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 651.387004] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 651.387004] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 651.387004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 661.212012] rcu-torture: rtc: ffffffff820d6fd0 ver: 2590 tfle: 0 rta: 2591 rtaf: 0 rtf: 2581 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 1750558 onoff: 128/128:132/133 34,3223:11,552 19099:13437 (HZ=1000) barrier: 0/0:0 cbflood: 608
> [ 661.214362] rcu-torture: Reader Pipe: 13245634209 14768 0 0 0 0 0 0 0 0 0
> [ 661.215321] rcu-torture: Reader Batch: 12930186166 315462811 0 0 0 0 0 0 0 0 0
> [ 661.216318] rcu-torture: Free-Block Circulation: 2590 2589 2588 2587 2586 2585 2584 2583 2582 2581 0
> [ 661.217515] ??? Writer stall state RTWS_EXP_SYNC(4) g4731 c4730 f0x0
> [ 661.218213] rcu_preempt: wait state: 3 ->state: 0x1
> [ 661.218764] rcu_sched: wait state: 1 ->state: 0x1
> [ 661.219294] rcu_bh: wait state: 1 ->state: 0x1
> [ 714.392003] INFO: rcu_preempt detected stalls on CPUs/tasks:
> [ 714.392003] 3-...: (1 GPs behind) idle=6cf/140000000000000/0 softirq=8341/8345 fqs=131969
> [ 714.392003] 8-...: (1 GPs behind) idle=503/140000000000001/0 softirq=9290/9294 fqs=131969
> [ 714.392003] 11-...: (1 GPs behind) idle=32f/140000000000001/0 softirq=8320/8323 fqs=131969
> [ 714.392003] 12-...: (1 GPs behind) idle=e2f/140000000000000/0 softirq=8014/8017 fqs=131969
> [ 714.392003] (detected by 0, t=399032 jiffies, g=4731, c=4730, q=10)
> [ 714.392003] Task dump for CPU 3:
> [ 714.392003] rcu_torture_rea R running task 14064 782 2 0x00000008
> [ 714.392003] 0000000000000a63 ffff88007c5bff58 ffff88007fb6cc00 0000000000000000
> [ 714.392003] ffff88007fa75e80 00000000cfc06af0 ffff88007c5bfd08 ffffffff813480d7
> [ 714.392003] ffff88007c5bfd30 ffffffff81091faf ffff88007fb6cc00 00000000cfc06af0
> [ 714.392003] Call Trace:
> [ 714.392003] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 714.392003] [<ffffffff81091faf>] ? queued_spin_lock_slowpath+0x6f/0x1a0
> [ 714.392003] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 714.392003] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 714.392003] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 714.392003] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 714.392003] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 714.392003] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 714.392003] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 714.392003] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 714.392003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 714.392003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 714.392003] Task dump for CPU 8:
> [ 714.392003] rcu_torture_rea R running task 14760 789 2 0x00000008
> [ 714.392003] ffffffff818af15c ffff88007c0f3ce8 ffff88007cdcbe80 ffff88007c91f080
> [ 714.392003] 0000000000000046 0000000000000000 ffff88007c0f4000 0000000000000000
> [ 714.392003] 00000047648a43ed 000000000000126f ffffffff820d6eb0 ffff88007c0f3d38
> [ 714.392003] Call Trace:
> [ 714.392003] [<ffffffff818af15c>] ? __schedule+0x38c/0xb00
> [ 714.392003] [<ffffffff818afd13>] ? preempt_schedule_irq+0x43/0x60
> [ 714.392003] [<ffffffff818b513b>] ? retint_kernel+0x1b/0x1d
> [ 714.392003] [<ffffffff818af94b>] ? _cond_resched+0xb/0x20
> [ 714.392003] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 714.392003] [<ffffffff810ad3ce>] ? rcu_torture_reader+0x11e/0x2e0
> [ 714.392003] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 714.392003] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 714.392003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 714.392003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 714.392003] Task dump for CPU 11:
> [ 714.392003] torture_onoff R running task 13416 798 2 0x00000008
> [ 714.392003] ffffffff8104a8b5 ffff88007ffdb600 ffff88007fb78f70 0000000000000002
> [ 714.392003] 0000000000000000 0000000000000000 ffff88007c6f7be8 ffff88007cafcb00
> [ 714.392003] ffff88007c6f7b70 ffffffff8104aa3e ffff88007c6f7bc8 ffffffff8104ac95
> [ 714.392003] Call Trace:
> [ 714.392003] [<ffffffff8104a8b5>] ? __bad_area_nosemaphore+0x75/0x1f0
> [ 714.392003] [<ffffffff8104aa3e>] ? bad_area_nosemaphore+0xe/0x10
> [ 714.392003] [<ffffffff8104ac95>] ? __do_page_fault+0x85/0x450
> [ 714.392003] [<ffffffff8104b06c>] ? do_page_fault+0xc/0x10
> [ 714.392003] [<ffffffff818b6422>] ? page_fault+0x22/0x30
> [ 714.392003] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 714.392003] [<ffffffff810b95c4>] ? timer_cpu_notify+0xe4/0x160
> [ 714.392003] [<ffffffff81073ea5>] ? notifier_call_chain+0x45/0x70
> [ 714.392003] [<ffffffff81073fc9>] ? __raw_notifier_call_chain+0x9/0x10
> [ 714.392003] [<ffffffff8105759e>] ? cpu_notify_nofail+0x1e/0x30
> [ 714.392003] [<ffffffff81057852>] ? _cpu_down+0x212/0x350
> [ 714.392003] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 714.392003] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 714.392003] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 714.392003] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 714.392003] [<ffffffff810579bf>] ? cpu_down+0x2f/0x50
> [ 714.392003] [<ffffffff811266b5>] ? torture_onoff+0x115/0x380
> [ 714.392003] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 714.392003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 714.392003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 714.392003] Task dump for CPU 12:
> [ 714.392003] rcu_torture_rea R running task 14064 786 2 0x00000008
> [ 714.392003] 0000000000000742 ffff88007c0dff58 ffff88007c0dfd20 ffffffff813311f5
> [ 714.392003] 000000000000062f 0000000f7fa2cc00 ffff88007fa2cc00 00000000cfc06af0
> [ 714.392003] 0000000000000001 00000000cfc06af0 ffff88007fa2cc00 00000000cfc06af0
> [ 714.392003] Call Trace:
> [ 714.392003] [<ffffffff813311f5>] ? nmi_trigger_all_cpu_backtrace+0x1b5/0x270
> [ 714.392003] [<ffffffff81093185>] ? do_raw_spin_lock+0x145/0x150
> [ 714.392003] [<ffffffff818b401f>] ? _raw_spin_lock_irqsave+0x1f/0x30
> [ 714.392003] [<ffffffff810b8faf>] ? lock_timer_base.isra.23+0x4f/0x70
> [ 714.392003] [<ffffffff810ba6fa>] ? mod_timer+0x6a/0x200
> [ 714.392003] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 714.392003] [<ffffffff810ad557>] ? rcu_torture_reader+0x2a7/0x2e0
> [ 714.392003] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 714.392003] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 714.392003] [<ffffffff810732f6>] ? kthread+0xd6/0xf0
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 714.392003] [<ffffffff818b499f>] ? ret_from_fork+0x3f/0x70
> [ 714.392003] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180

> [ 0.000000] Linux version 4.5.0-rc1+ (root@insomnia) (gcc version 5.3.0 (GCC) ) #14 SMP PREEMPT Wed Mar 30 20:01:04 CST 2016
> [ 0.000000] Command line: selinux=0 console=ttyS0 rcutorture.onoff_interval=1 rcutorture.onff_holdoff=30
> [ 0.000000] x86/fpu: Legacy x87 FPU detected.
> [ 0.000000] x86/fpu: Using 'lazy' FPU context switches.
> [ 0.000000] e820: BIOS-provided physical RAM map:
> [ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
> [ 0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000007ffdefff] usable
> [ 0.000000] BIOS-e820: [mem 0x000000007ffdf000-0x000000007fffffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved
> [ 0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
> [ 0.000000] NX (Execute Disable) protection: active
> [ 0.000000] SMBIOS 2.8 present.
> [ 0.000000] e820: last_pfn = 0x7ffdf max_arch_pfn = 0x400000000
> [ 0.000000] x86/PAT: Configuration [0-7]: WB WC UC- UC WB WC UC- WT
> [ 0.000000] found SMP MP-table at [mem 0x000f6a50-0x000f6a5f] mapped at [ffff8800000f6a50]
> [ 0.000000] Scanning 1 areas for low memory corruption
> [ 0.000000] Using GB pages for direct mapping
> [ 0.000000] RAMDISK: [mem 0x7fcd4000-0x7ffcffff]
> [ 0.000000] ACPI: Early table checksum verification disabled
> [ 0.000000] ACPI: RSDP 0x00000000000F6A00 000014 (v00 BOCHS )
> [ 0.000000] ACPI: RSDT 0x000000007FFE1580 000034 (v01 BOCHS BXPCRSDT 00000001 BXPC 00000001)
> [ 0.000000] ACPI: FACP 0x000000007FFE061A 000074 (v01 BOCHS BXPCFACP 00000001 BXPC 00000001)
> [ 0.000000] ACPI: DSDT 0x000000007FFDFA80 000B9A (v01 BOCHS BXPCDSDT 00000001 BXPC 00000001)
> [ 0.000000] ACPI: FACS 0x000000007FFDFA40 000040
> [ 0.000000] ACPI: SSDT 0x000000007FFE068E 000DCA (v01 BOCHS BXPCSSDT 00000001 BXPC 00000001)
> [ 0.000000] ACPI: APIC 0x000000007FFE1458 0000F0 (v01 BOCHS BXPCAPIC 00000001 BXPC 00000001)
> [ 0.000000] ACPI: HPET 0x000000007FFE1548 000038 (v01 BOCHS BXPCHPET 00000001 BXPC 00000001)
> [ 0.000000] No NUMA configuration found
> [ 0.000000] Faking a node at [mem 0x0000000000000000-0x000000007ffdefff]
> [ 0.000000] NODE_DATA(0) allocated [mem 0x7ffdb000-0x7ffdefff]
> [ 0.000000] Zone ranges:
> [ 0.000000] DMA [mem 0x0000000000001000-0x0000000000ffffff]
> [ 0.000000] DMA32 [mem 0x0000000001000000-0x000000007ffdefff]
> [ 0.000000] Normal empty
> [ 0.000000] Movable zone start for each node
> [ 0.000000] Early memory node ranges
> [ 0.000000] node 0: [mem 0x0000000000001000-0x000000000009efff]
> [ 0.000000] node 0: [mem 0x0000000000100000-0x000000007ffdefff]
> [ 0.000000] Initmem setup node 0 [mem 0x0000000000001000-0x000000007ffdefff]
> [ 0.000000] ACPI: PM-Timer IO Port: 0x608
> [ 0.000000] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1])
> [ 0.000000] IOAPIC[0]: apic_id 0, version 17, address 0xfec00000, GSI 0-23
> [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
> [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level)
> [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
> [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level)
> [ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level)
> [ 0.000000] Using ACPI (MADT) for SMP configuration information
> [ 0.000000] ACPI: HPET id: 0x8086a201 base: 0xfed00000
> [ 0.000000] smpboot: Allowing 16 CPUs, 0 hotplug CPUs
> [ 0.000000] PM: Registered nosave memory: [mem 0x00000000-0x00000fff]
> [ 0.000000] PM: Registered nosave memory: [mem 0x0009f000-0x0009ffff]
> [ 0.000000] PM: Registered nosave memory: [mem 0x000a0000-0x000effff]
> [ 0.000000] PM: Registered nosave memory: [mem 0x000f0000-0x000fffff]
> [ 0.000000] e820: [mem 0x80000000-0xfeffbfff] available for PCI devices
> [ 0.000000] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1910969940391419 ns
> [ 0.000000] setup_percpu: NR_CPUS:16 nr_cpumask_bits:16 nr_cpu_ids:16 nr_node_ids:1
> [ 0.000000] PERCPU: Embedded 32 pages/cpu @ffff88007fa00000 s92008 r8192 d30872 u131072
> [ 0.000000] Built 1 zonelists in Node order, mobility grouping on. Total pages: 515944
> [ 0.000000] Policy zone: DMA32
> [ 0.000000] Kernel command line: selinux=0 console=ttyS0 rcutorture.onoff_interval=1 rcutorture.onff_holdoff=30
> [ 0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes)
> [ 0.000000] Memory: 2040780K/2096628K available (8931K kernel code, 1258K rwdata, 3700K rodata, 1092K init, 984K bss, 55848K reserved, 0K cma-reserved)
> [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=16, Nodes=1
> [ 0.000000] Preemptible hierarchical RCU implementation.
> [ 0.000000] RCU debugfs-based tracing is enabled.
> [ 0.000000] CONFIG_RCU_FANOUT set to non-default value of 2
> [ 0.000000] RCU torture testing starts during boot.
> [ 0.000000] Four(or more)-level hierarchy is enabled.
> [ 0.000000] Build-time adjustment of leaf fanout to 2.
> [ 0.000000] RCU kthread priority: 2.
> [ 0.000000] NR_IRQS:4352 nr_irqs:552 16
> [ 0.000000] Console: colour *CGA 80x25
> [ 0.000000] console [ttyS0] enabled
> [ 0.000000] clocksource: hpet: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604467 ns
> [ 0.000000] tsc: Fast TSC calibration using PIT
> [ 0.000000] tsc: Detected 3466.832 MHz processor
> [ 0.003013] Calibrating delay loop (skipped), value calculated using timer frequency.. 6933.66 BogoMIPS (lpj=3466832)
> [ 0.003833] pid_max: default: 32768 minimum: 301
> [ 0.004006] ACPI: Core revision 20160108
> [ 0.005469] ACPI: 2 ACPI AML tables successfully acquired and loaded
> [ 0.005978]
> [ 0.006019] Security Framework initialized
> [ 0.006345] SELinux: Disabled at boot.
> [ 0.006740] Dentry cache hash table entries: 262144 (order: 9, 2097152 bytes)
> [ 0.007361] Inode-cache hash table entries: 131072 (order: 8, 1048576 bytes)
> [ 0.008155] Mount-cache hash table entries: 4096 (order: 3, 32768 bytes)
> [ 0.008679] Mountpoint-cache hash table entries: 4096 (order: 3, 32768 bytes)
> [ 0.009966] mce: CPU supports 10 MCE banks
> [ 0.010033] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0
> [ 0.010446] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0, 1GB 0
> [ 0.012422] Freeing SMP alternatives memory: 32K (ffffffff8204d000 - ffffffff82055000)
> [ 0.013352] Switched APIC routing to physical flat.
> [ 0.014528] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1
> [ 0.024122] smpboot: CPU0: Intel(R) Xeon(R) CPU X5690 @ 3.47GHz (family: 0x6, model: 0x2c, stepping: 0x2)
> [ 0.025000] Performance Events: 16-deep LBR, Westmere events, Intel PMU driver.
> [ 0.025496] perf_event_intel: CPUID marked event: 'bus cycles' unavailable
> [ 0.026006] ... version: 2
> [ 0.026368] ... bit width: 48
> [ 0.026737] ... generic registers: 4
> [ 0.027003] ... value mask: 0000ffffffffffff
> [ 0.027478] ... max period: 000000007fffffff
> [ 0.027953] ... fixed-purpose events: 3
> [ 0.028003] ... event mask: 000000070000000f
> [ 0.037037] x86: Booting SMP configuration:
> [ 0.037492] .... node #0, CPUs: #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15
> [ 0.995027] x86: Booted up 1 node, 16 CPUs
> [ 0.995371] smpboot: Total of 16 processors activated (111391.08 BogoMIPS)
> [ 0.997856] devtmpfs: initialized
> [ 0.998418] kworker/u32:0 (98) used greatest stack depth: 13928 bytes left
> [ 0.998561] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1911260446275000 ns
> [ 0.998925] RTC time: 12:20:59, date: 03/30/16
> [ 0.999018] NET: Registered protocol family 16
> [ 1.005018] cpuidle: using governor menu
> [ 1.005421] ACPI: bus type PCI registered
> [ 1.005818] PCI: Using configuration type 1 for base access
> [ 1.005747] kworker/u32:3 (115) used greatest stack depth: 13920 bytes left
> [ 1.021340] HugeTLB registered 2 MB page size, pre-allocated 0 pages
> [ 1.022603] ACPI: Added _OSI(Module Device)
> [ 1.022952] ACPI: Added _OSI(Processor Device)
> [ 1.023005] ACPI: Added _OSI(3.0 _SCP Extensions)
> [ 1.023355] ACPI: Added _OSI(Processor Aggregator Device)
> [ 1.025022] ACPI: Interpreter enabled
> [ 1.025320] ACPI: (supports S0 S3 S4 S5)
> [ 1.025667] ACPI: Using IOAPIC for interrupt routing
> [ 1.026046] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug
> [ 1.032012] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])
> [ 1.032602] acpi PNP0A03:00: _OSC: OS supports [ASPM ClockPM Segments MSI]
> [ 1.033009] acpi PNP0A03:00: _OSC failed (AE_NOT_FOUND); disabling ASPM
> [ 1.033650] acpi PNP0A03:00: fail to add MMCONFIG information, can't access extended PCI configuration space under this bridge.
> [ 1.034072] PCI host bridge to bus 0000:00
> [ 1.034468] pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window]
> [ 1.034968] pci_bus 0000:00: root bus resource [io 0x0d00-0xffff window]
> [ 1.035004] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff window]
> [ 1.035585] pci_bus 0000:00: root bus resource [mem 0x80000000-0xfebfffff window]
> [ 1.036017] pci_bus 0000:00: root bus resource [bus 00-ff]
> [ 1.039433] pci 0000:00:01.1: legacy IDE quirk: reg 0x10: [io 0x01f0-0x01f7]
> [ 1.039968] pci 0000:00:01.1: legacy IDE quirk: reg 0x14: [io 0x03f6]
> [ 1.040005] pci 0000:00:01.1: legacy IDE quirk: reg 0x18: [io 0x0170-0x0177]
> [ 1.040517] pci 0000:00:01.1: legacy IDE quirk: reg 0x1c: [io 0x0376]
> [ 1.041368] pci 0000:00:01.3: quirk: [io 0x0600-0x063f] claimed by PIIX4 ACPI
> [ 1.041916] pci 0000:00:01.3: quirk: [io 0x0700-0x070f] claimed by PIIX4 SMB
> [ 1.042815] ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11)
> [ 1.043205] ACPI: PCI Interrupt Link [LNKB] (IRQs 5 *10 11)
> [ 1.043758] ACPI: PCI Interrupt Link [LNKC] (IRQs 5 10 *11)
> [ 1.044198] ACPI: PCI Interrupt Link [LNKD] (IRQs 5 10 *11)
> [ 1.044713] ACPI: PCI Interrupt Link [LNKS] (IRQs *9)
> [ 1.046143] ACPI: Enabled 16 GPEs in block 00 to 0F
> [ 1.046807] vgaarb: loaded
> [ 1.047110] SCSI subsystem initialized
> [ 1.047744] ACPI: bus type USB registered
> [ 1.048059] usbcore: registered new interface driver usbfs
> [ 1.048522] usbcore: registered new interface driver hub
> [ 1.049121] usbcore: registered new device driver usb
> [ 1.049610] pps_core: LinuxPPS API ver. 1 registered
> [ 1.049993] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <[email protected]>
> [ 1.050037] PTP clock support registered
> [ 1.050709] Advanced Linux Sound Architecture Driver Initialized.
> [ 1.051063] PCI: Using ACPI for IRQ routing
> [ 1.051868] NetLabel: Initializing
> [ 1.052004] NetLabel: domain hash size = 128
> [ 1.052344] NetLabel: protocols = UNLABELED CIPSOv4
> [ 1.052731] NetLabel: unlabeled traffic allowed by default
> [ 1.053340] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0
> [ 1.053767] hpet0: 3 comparators, 64-bit 100.000000 MHz counter
> [ 1.060502] clocksource: Switched to clocksource hpet
> [ 1.067708] VFS: Disk quotas dquot_6.6.0
> [ 1.068138] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
> [ 1.068861] pnp: PnP ACPI init
> [ 1.069996] pnp: PnP ACPI: found 5 devices
> [ 1.083114] clocksource: acpi_pm: mask: 0xffffff max_cycles: 0xffffff, max_idle_ns: 2085701024 ns
> [ 1.084330] NET: Registered protocol family 2
> [ 1.084798] TCP established hash table entries: 16384 (order: 5, 131072 bytes)
> [ 1.085547] TCP bind hash table entries: 16384 (order: 7, 524288 bytes)
> [ 1.086253] TCP: Hash tables configured (established 16384 bind 16384)
> [ 1.086773] UDP hash table entries: 1024 (order: 4, 98304 bytes)
> [ 1.087369] UDP-Lite hash table entries: 1024 (order: 4, 98304 bytes)
> [ 1.087919] NET: Registered protocol family 1
> [ 1.088579] RPC: Registered named UNIX socket transport module.
> [ 1.089121] RPC: Registered udp transport module.
> [ 1.089484] RPC: Registered tcp transport module.
> [ 1.089831] RPC: Registered tcp NFSv4.1 backchannel transport module.
> [ 1.090460] pci 0000:00:00.0: Limiting direct PCI/PCI transfers
> [ 1.090902] pci 0000:00:01.0: PIIX3: Enabling Passive Release
> [ 1.091511] pci 0000:00:01.0: Activating ISA DMA hang workarounds
> [ 1.092093] Unpacking initramfs...
> [ 1.134394] Freeing initrd memory: 3056K (ffff88007fcd4000 - ffff88007ffd0000)
> [ 1.137993] Scanning for low memory corruption every 60 seconds
> [ 1.138767] rcu-torture:--- Start of test: nreaders=15 nfakewriters=4 stat_interval=60 verbose=1 test_no_idle_hz=1 shuffle_interval=3 stutter=5 irqreader=1 fqs_duration=0 fqs_holdoff=0 fqs_stutter=3 test_boost=1/0 test_boost_interval=7 test_boost_duration=4 shutdown_secs=0 stall_cpu=0 stall_cpu_holdoff=10 n_barrier_cbs=0 onoff_interval=1 onoff_holdoff=0
> [ 1.141407] rcu-torture: Creating rcu_torture_writer task
> [ 1.141864] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.141869] rcu-torture: rcu_torture_writer task started
> [ 1.141870] rcu-torture: Grace periods expedited from boot/sysfs for rcu,
> [ 1.141870] rcu-torture: Testing of dynamic grace-period expediting diabled.
> [ 1.143988] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.143990] rcu-torture: rcu_torture_fakewriter task started
> [ 1.144986] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.144990] rcu-torture: rcu_torture_fakewriter task started
> [ 1.146065] rcu-torture: Creating rcu_torture_fakewriter task
> [ 1.146120] rcu-torture: rcu_torture_fakewriter task started
> [ 1.147143] rcu-torture: rcu_torture_fakewriter task started
> [ 1.147141] rcu-torture: Creating rcu_torture_reader task
> [ 1.147233] rcu-torture: Creating rcu_torture_reader task
> [ 1.147235] rcu-torture: rcu_torture_reader task started
> [ 1.147314] rcu-torture: Creating rcu_torture_reader task
> [ 1.147317] rcu-torture: rcu_torture_reader task started
> [ 1.147357] rcu-torture: Creating rcu_torture_reader task
> [ 1.147363] rcu-torture: rcu_torture_reader task started
> [ 1.147403] rcu-torture: Creating rcu_torture_reader task
> [ 1.147406] rcu-torture: rcu_torture_reader task started
> [ 1.147479] rcu-torture: Creating rcu_torture_reader task
> [ 1.147483] rcu-torture: rcu_torture_reader task started
> [ 1.147543] rcu-torture: Creating rcu_torture_reader task
> [ 1.147549] rcu-torture: rcu_torture_reader task started
> [ 1.147607] rcu-torture: Creating rcu_torture_reader task
> [ 1.147611] rcu-torture: rcu_torture_reader task started
> [ 1.147669] rcu-torture: Creating rcu_torture_reader task
> [ 1.147679] rcu-torture: rcu_torture_reader task started
> [ 1.147729] rcu-torture: Creating rcu_torture_reader task
> [ 1.147740] rcu-torture: rcu_torture_reader task started
> [ 1.149119] rcu-torture: Creating rcu_torture_reader task
> [ 1.149123] rcu-torture: rcu_torture_reader task started
> [ 1.149990] rcu-torture: Creating rcu_torture_reader task
> [ 1.150107] rcu-torture: rcu_torture_reader task started
> [ 1.150142] rcu-torture: Creating rcu_torture_reader task
> [ 1.150147] rcu-torture: rcu_torture_reader task started
> [ 1.150208] rcu-torture: Creating rcu_torture_reader task
> [ 1.150212] rcu-torture: rcu_torture_reader task started
> [ 1.151160] rcu-torture: Creating rcu_torture_reader task
> [ 1.151221] rcu-torture: Creating rcu_torture_stats task
> [ 1.151253] rcu-torture: rcu_torture_reader task started
> [ 1.151277] rcu-torture: Creating torture_shuffle task
> [ 1.151284] rcu-torture: rcu_torture_stats task started
> [ 1.152080] rcu-torture: Creating torture_stutter task
> [ 1.152111] rcu-torture: torture_shuffle task started
> [ 1.152112] rcu-torture: rcu_torture_reader task started
> [ 1.154114] rcu-torture: Creating torture_onoff task
> [ 1.154118] rcu-torture: torture_stutter task started
> [ 1.211086] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.211090] rcu-torture: torture_onoff task started
> [ 1.211092] rcu-torture:torture_onoff task: offlining 13
> [ 1.213955] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.214122] rcu-torture: rcu_torture_cbflood task started
> [ 1.218078] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.218734] rcu-torture: Creating rcu_torture_cbflood task
> [ 1.219118] rcu-torture: rcu_torture_cbflood task started
> [ 1.223173] rcu-torture: rcu_torture_cbflood task started
> [ 1.223205] rcu-torture: rcu_torture_cbflood task started
> [ 1.243284] rcu-torture:torture_onoff task: offlined 13
> [ 1.243675] futex hash table entries: 4096 (order: 6, 262144 bytes)
> [ 1.243736] audit: initializing netlink subsys (disabled)
> [ 1.243747] audit: type=2000 audit(1459340459.243:1): initialized
> [ 1.313263] NFS: Registering the id_resolver key type
> [ 1.313829] Key type id_resolver registered
> [ 1.314376] Key type id_legacy registered
> [ 1.354157] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 251)
> [ 1.354945] io scheduler noop registered
> [ 1.356446] io scheduler deadline registered
> [ 1.356923] io scheduler cfq registered (default)
> [ 1.357612] pci_hotplug: PCI Hot Plug PCI Core version: 0.5
> [ 1.359433] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0
> [ 1.361337] ACPI: Power Button [PWRF]
> [ 1.362621] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
> [ 1.399062] 00:04: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
> [ 1.400539] Non-volatile memory driver v1.3
> [ 1.401156] Linux agpgart interface v0.103
> [ 1.401710] [drm] Initialized drm 1.1.0 20060810
> [ 1.429307] loop: module loaded
> [ 1.434097] scsi host0: ata_piix
> [ 1.435777] scsi host1: ata_piix
> [ 1.436290] ata1: PATA max MWDMA2 cmd 0x1f0 ctl 0x3f6 bmdma 0xc000 irq 14
> [ 1.438073] ata2: PATA max MWDMA2 cmd 0x170 ctl 0x376 bmdma 0xc008 irq 15
> [ 1.438894] e100: Intel(R) PRO/100 Network Driver, 3.5.24-k2-NAPI
> [ 1.439675] e100: Copyright(c) 1999-2006 Intel Corporation
> [ 1.440407] e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI
> [ 1.442252] e1000: Copyright (c) 1999-2006 Intel Corporation.
> [ 1.442889] sky2: driver version 1.30
> [ 1.443530] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver
> [ 1.444322] ehci-pci: EHCI PCI platform driver
> [ 1.444823] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver
> [ 1.445569] ohci-pci: OHCI PCI platform driver
> [ 1.449090] uhci_hcd: USB Universal Host Controller Interface driver
> [ 1.449826] usbcore: registered new interface driver usblp
> [ 1.451533] usbcore: registered new interface driver usb-storage
> [ 1.452336] i8042: PNP: PS/2 Controller [PNP0303:KBD,PNP0f13:MOU] at 0x60,0x64 irq 1,12
> [ 1.455238] serio: i8042 KBD port at 0x60,0x64 irq 1
> [ 1.457074] serio: i8042 AUX port at 0x60,0x64 irq 12
> [ 1.457752] mousedev: PS/2 mouse device common for all mice
> [ 1.458778] input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input1
> [ 1.461184] rtc_cmos 00:00: RTC can wake from S4
> [ 1.463104] rtc_cmos 00:00: rtc core: registered rtc_cmos as rtc0
> [ 1.465953] rtc_cmos 00:00: alarms up to one day, 114 bytes nvram, hpet irqs
> [ 1.468306] device-mapper: ioctl: 4.34.0-ioctl (2015-10-28) initialised: [email protected]
> [ 1.469385] hidraw: raw HID events driver (C) Jiri Kosina
> [ 1.470275] usbcore: registered new interface driver usbhid
> [ 1.470884] usbhid: USB HID core driver
> [ 1.471898] Netfilter messages via NETLINK v0.30.
> [ 1.472530] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
> [ 1.474410] ctnetlink v0.93: registering with nfnetlink.
> [ 1.550099] ip_tables: (C) 2000-2006 Netfilter Core Team
> [ 1.562112] Initializing XFRM netlink socket
> [ 1.562766] NET: Registered protocol family 10
> [ 1.566194] ip6_tables: (C) 2000-2006 Netfilter Core Team
> [ 1.651113] sit: IPv6 over IPv4 tunneling driver
> [ 1.651774] NET: Registered protocol family 17
> [ 1.652402] Key type dns_resolver registered
> [ 1.656232] microcode: CPU0 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.656892] microcode: CPU1 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.657595] microcode: CPU2 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.658311] microcode: CPU3 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.659050] microcode: CPU4 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.659713] microcode: CPU5 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.664080] microcode: CPU6 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.664717] microcode: CPU7 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.666372] microcode: CPU8 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.667095] microcode: CPU9 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.667730] microcode: CPU10 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.668984] microcode: CPU11 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.671078] microcode: CPU12 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.671735] microcode: CPU14 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.675111] microcode: CPU15 sig=0x206c2, pf=0x1, revision=0x1
> [ 1.675751] microcode: Microcode Update Driver: v2.01 <[email protected]>, Peter Oruba
> [ 1.677129] registered taskstats version 1
> [ 1.678189] Magic number: 8:778:330
> [ 1.678610] tty tty51: hash matches
> [ 1.679080] console [netcon0] enabled
> [ 1.679486] netconsole: network logging started
> [ 1.681203] ALSA device list:
> [ 1.681517] No soundcards found.
> [ 1.686591] Freeing unused kernel memory: 1092K (ffffffff81f3c000 - ffffffff8204d000)
> [ 1.688489] Write protecting the kernel read-only data: 14336k
> [ 1.733287] Freeing unused kernel memory: 1296K (ffff8800018bc000 - ffff880001a00000)
> [ 1.737138] Freeing unused kernel memory: 396K (ffff880001d9d000 - ffff880001e00000)
> :: running early hook [udev]
> Warning: /lib/modules/4.5.0-rc1+/modules.devname not found - ignoring
> [ 1.827599] random: systemd-tmpfile urandom read with 3 bits of entropy available
> [ 1.828672] systemd-tmpfile (1173) used greatest stack depth: 13896 bytes left
> starting version 228
> :: running hook [udev]
> :: Triggering uevents...
> [ 2.069991] input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input3
> [ 2.135095] tsc: Refined TSC clocksource calibration: 3466.788 MHz
> [ 2.135783] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x31f8c2dfb06, max_idle_ns: 440795261134 ns
> [ 2.247097] rcu-torture:torture_onoff task: offlining 2
> ERROR: device '' not found. Skipping fsck.
> ERROR: Unable to find root device ''.
> You are being dropped to a recovery shell
> Type 'exit' to try and continue booting
> [ 2.386672] smpboot: CPU 2 is now offline
> sh: can't access tty; job control turned off
> [rootfs /]# [ 2.397205] rcu-torture:torture_onoff task: offlined 2
> [ 2.410066] hrtimer: interrupt took 3042970 ns
> [ 3.146410] clocksource: Switched to clocksource tsc
> [ 3.399958] rcu-torture:torture_onoff task: onlining 2
> [ 3.460067] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 3.547187] rcu-torture:torture_onoff task: onlined 2
> [ 4.546024] rcu-torture:torture_onoff task: offlining 11
> [ 4.693029] smpboot: CPU 11 is now offline
> [ 4.741119] rcu-torture:torture_onoff task: offlined 11
> [ 5.749377] rcu-torture:torture_onoff task: offlining 14
> [ 5.949978] smpboot: CPU 14 is now offline
> [ 5.963969] rcu-torture:torture_onoff task: offlined 14
> [ 6.964014] rcu-torture:torture_onoff task: offlining 10
> [ 7.053009] smpboot: CPU 10 is now offline
> [ 7.110906] rcu-torture:torture_onoff task: offlined 10
> [ 9.111009] rcu-torture:torture_onoff task: offlining 15
> [ 9.168815] smpboot: CPU 15 is now offline
> [ 9.223617] rcu-torture:torture_onoff task: offlined 15
> [ 10.224013] rcu-torture:torture_onoff task: offlining 7
> [ 10.279743] smpboot: CPU 7 is now offline
> [ 10.334679] rcu-torture:torture_onoff task: offlined 7
> [ 11.353015] rcu-torture:torture_onoff task: offlining 8
> [ 11.399709] smpboot: CPU 8 is now offline
> [ 11.452791] rcu-torture:torture_onoff task: offlined 8
> [ 12.453012] rcu-torture:torture_onoff task: offlining 2
> [ 12.692639] smpboot: CPU 2 is now offline
> [ 12.700748] rcu-torture:torture_onoff task: offlined 2
> [ 13.701030] rcu-torture:torture_onoff task: offlining 4
> [ 13.805923] smpboot: CPU 4 is now offline
> [ 13.810522] rcu-torture:torture_onoff task: offlined 4
> [ 14.812009] rcu-torture:torture_onoff task: onlining 14
> [ 14.853417] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 14.978121] rcu-torture:torture_onoff task: onlined 14
> [ 15.993226] rcu-torture:torture_onoff task: offlining 1
> [ 16.075508] smpboot: CPU 1 is now offline
> [ 16.079509] rcu-torture:torture_onoff task: offlined 1
> [ 17.080012] rcu-torture:torture_onoff task: onlining 11
> [ 17.134382] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 17.161137] rcu-torture:torture_onoff task: onlined 11
> [ 18.161010] rcu-torture:torture_onoff task: onlining 13
> [ 18.215414] smpboot: Booting Node 0 Processor 13 APIC 0xd
> [ 18.242122] microcode: CPU13 sig=0x206c2, pf=0x1, revision=0x1
> [ 18.242769] rcu-torture:torture_onoff task: onlined 13
> [ 19.243011] rcu-torture:torture_onoff task: onlining 7
> [ 19.297658] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 19.351182] rcu-torture:torture_onoff task: onlined 7
> [ 20.351029] rcu-torture:torture_onoff task: offlining 7
> [ 20.408213] smpboot: CPU 7 is now offline
> [ 20.463500] rcu-torture:torture_onoff task: offlined 7
> [ 21.464012] rcu-torture:torture_onoff task: onlining 15
> [ 21.490634] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 21.617119] rcu-torture:torture_onoff task: onlined 15
> [ 22.617010] rcu-torture:torture_onoff task: offlining 14
> [ 22.675687] smpboot: CPU 14 is now offline
> [ 22.681349] rcu-torture:torture_onoff task: offlined 14
> [ 23.681012] rcu-torture:torture_onoff task: onlining 4
> [ 23.731637] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 23.871156] rcu-torture:torture_onoff task: onlined 4
> [ 24.871012] rcu-torture:torture_onoff task: onlining 1
> [ 24.900714] x86: Booting SMP configuration:
> [ 24.901186] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 24.950179] rcu-torture:torture_onoff task: onlined 1
> [ 25.950013] rcu-torture:torture_onoff task: offlining 3
> [ 26.057786] smpboot: CPU 3 is now offline
> [ 26.064052] rcu-torture:torture_onoff task: offlined 3
> [ 27.064012] rcu-torture:torture_onoff task: offlining 12
> [ 27.119717] smpboot: CPU 12 is now offline
> [ 27.174923] rcu-torture:torture_onoff task: offlined 12
> [ 28.175012] rcu-torture:torture_onoff task: offlining 11
> [ 28.230573] smpboot: CPU 11 is now offline
> [ 28.285886] rcu-torture:torture_onoff task: offlined 11
> [ 30.286014] rcu-torture:torture_onoff task: onlining 10
> [ 30.294771] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 30.321158] rcu-torture:torture_onoff task: onlined 10
> [ 31.321012] rcu-torture:torture_onoff task: offlining 10
> [ 31.382675] smpboot: CPU 10 is now offline
> [ 31.388604] rcu-torture:torture_onoff task: offlined 10
> [ 32.398957] rcu-torture:torture_onoff task: offlining 15
> [ 32.483642] smpboot: CPU 15 is now offline
> [ 32.503185] rcu-torture:torture_onoff task: offlined 15
> [ 33.517435] rcu-torture:torture_onoff task: offlining 9
> [ 33.544327] smpboot: CPU 9 is now offline
> [ 33.643562] rcu-torture:torture_onoff task: offlined 9
> [ 34.643009] rcu-torture:torture_onoff task: onlining 8
> [ 34.691663] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 34.940504] rcu-torture:torture_onoff task: onlined 8
> [ 35.940017] rcu-torture:torture_onoff task: onlining 12
> [ 35.977744] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 36.027219] rcu-torture:torture_onoff task: onlined 12
> [ 37.027017] rcu-torture:torture_onoff task: offlining 5
> [ 37.086642] smpboot: CPU 5 is now offline
> [ 37.140600] rcu-torture:torture_onoff task: offlined 5
> [ 38.140057] rcu-torture:torture_onoff task: offlining 1
> [ 38.195592] smpboot: CPU 1 is now offline
> [ 38.249549] rcu-torture:torture_onoff task: offlined 1
> [ 39.249060] rcu-torture:torture_onoff task: onlining 2
> [ 39.303563] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 39.330313] rcu-torture:torture_onoff task: onlined 2
> [ 40.330013] rcu-torture:torture_onoff task: onlining 7
> [ 40.384528] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 40.410295] rcu-torture:torture_onoff task: onlined 7
> [ 41.410012] rcu-torture:torture_onoff task: onlining 15
> [ 41.445849] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 41.595119] rcu-torture:torture_onoff task: onlined 15
> [ 42.595017] rcu-torture:torture_onoff task: onlining 11
> [ 42.640687] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 42.897158] rcu-torture:torture_onoff task: onlined 11
> [ 43.918123] rcu-torture:torture_onoff task: offlining 11
> [ 44.002293] smpboot: CPU 11 is now offline
> [ 44.030843] rcu-torture:torture_onoff task: offlined 11
> [ 45.069287] rcu-torture:torture_onoff task: onlining 14
> [ 45.110852] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 45.190158] rcu-torture:torture_onoff task: onlined 14
> [ 46.200280] rcu-torture:torture_onoff task: onlining 3
> [ 46.254642] smpboot: Booting Node 0 Processor 3 APIC 0x3
> [ 46.281296] rcu-torture:torture_onoff task: onlined 3
> [ 47.281108] rcu-torture:torture_onoff task: offlining 12
> [ 47.354083] smpboot: CPU 12 is now offline
> [ 47.408502] rcu-torture:torture_onoff task: offlined 12
> [ 48.409053] rcu-torture:torture_onoff task: offlining 7
> [ 48.468196] smpboot: CPU 7 is now offline
> [ 48.522054] rcu-torture:torture_onoff task: offlined 7
> [ 49.522011] rcu-torture:torture_onoff task: onlining 5
> [ 49.576662] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 49.620233] rcu-torture:torture_onoff task: onlined 5
> [ 50.620020] rcu-torture:torture_onoff task: offlining 5
> [ 50.675691] smpboot: CPU 5 is now offline
> [ 50.730810] rcu-torture:torture_onoff task: offlined 5
> [ 51.731011] rcu-torture:torture_onoff task: onlining 7
> [ 51.755781] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 51.939999] rcu-torture:torture_onoff task: onlined 7
> [ 52.940014] rcu-torture:torture_onoff task: onlining 10
> [ 52.977706] smpboot: Booting Node 0 Processor 10 APIC 0xa
> [ 53.087157] rcu-torture:torture_onoff task: onlined 10
> [ 55.087012] rcu-torture:torture_onoff task: offlining 7
> [ 55.185286] smpboot: CPU 7 is now offline
> [ 55.223166] rcu-torture:torture_onoff task: offlined 7
> [ 57.223027] rcu-torture:torture_onoff task: onlining 9
> [ 57.277812] smpboot: Booting Node 0 Processor 9 APIC 0x9
> [ 57.453204] rcu-torture:torture_onoff task: onlined 9
> [ 58.453025] rcu-torture:torture_onoff task: offlining 4
> [ 58.508771] smpboot: CPU 4 is now offline
> [ 58.563853] rcu-torture:torture_onoff task: offlined 4
> [ 59.564021] rcu-torture:torture_onoff task: offlining 15
> [ 59.619737] smpboot: CPU 15 is now offline
> [ 59.674752] rcu-torture:torture_onoff task: offlined 15
> [ 60.675011] rcu-torture:torture_onoff task: onlining 11
> [ 60.729655] smpboot: Booting Node 0 Processor 11 APIC 0xb
> [ 60.760167] rcu-torture:torture_onoff task: onlined 11
> [ 61.151063] rcu-torture: rtc: ffffffff820d6d90 ver: 486 tfle: 0 rta: 486 rtaf: 0 rtf: 477 rtmbe: 0 rtbke: 0 rtbre: 0 rtbf: 0 rtb: 0 nt: 190132 onoff: 22/22:28/28 35,302:36,248 3043:3316 (HZ=1000) barrier: 0/0:0 cbflood: 111
> [ 61.152622] rcu-torture: Reader Pipe: 1535993020 2788 0 0 0 0 0 0 0 0 0
> [ 61.153284] rcu-torture: Reader Batch: 1498299548 37696260 0 0 0 0 0 0 0 0 0
> [ 61.153956] rcu-torture: Free-Block Circulation: 485 485 484 483 482 481 480 479 478 477 0
> [ 61.761294] rcu-torture:torture_onoff task: onlining 7
> [ 61.775714] smpboot: Booting Node 0 Processor 7 APIC 0x7
> [ 61.863159] rcu-torture:torture_onoff task: onlined 7
> [ 62.863011] rcu-torture:torture_onoff task: onlining 4
> [ 62.871773] smpboot: Booting Node 0 Processor 4 APIC 0x4
> [ 63.031172] rcu-torture:torture_onoff task: onlined 4
> [ 65.031013] rcu-torture:torture_onoff task: onlining 12
> [ 65.080798] smpboot: Booting Node 0 Processor 12 APIC 0xc
> [ 65.275156] rcu-torture:torture_onoff task: onlined 12
> [ 66.275024] rcu-torture:torture_onoff task: offlining 8
> [ 66.389965] smpboot: CPU 8 is now offline
> [ 66.446833] rcu-torture:torture_onoff task: offlined 8
> [ 67.447011] rcu-torture:torture_onoff task: offlining 4
> [ 67.519976] smpboot: CPU 4 is now offline
> [ 67.574933] rcu-torture:torture_onoff task: offlined 4
> [ 68.575012] rcu-torture:torture_onoff task: offlining 14
> [ 68.630792] smpboot: CPU 14 is now offline
> [ 68.685836] rcu-torture:torture_onoff task: offlined 14
> [ 69.686010] rcu-torture:torture_onoff task: onlining 8
> [ 69.740781] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 69.767219] rcu-torture:torture_onoff task: onlined 8
> [ 70.767012] rcu-torture:torture_onoff task: onlining 1
> [ 70.821811] x86: Booting SMP configuration:
> [ 70.822290] smpboot: Booting Node 0 Processor 1 APIC 0x1
> [ 70.849223] rcu-torture:torture_onoff task: onlined 1
> [ 71.849011] rcu-torture:torture_onoff task: offlining 8
> [ 71.910796] smpboot: CPU 8 is now offline
> [ 71.932831] rcu-torture:torture_onoff task: offlined 8
> [ 72.933011] rcu-torture:torture_onoff task: onlining 14
> [ 72.974767] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 73.058172] rcu-torture:torture_onoff task: onlined 14
> [ 74.058013] rcu-torture:torture_onoff task: offlining 2
> [ 74.109813] smpboot: CPU 2 is now offline
> [ 74.162576] rcu-torture:torture_onoff task: offlined 2
> [ 75.198166] rcu-torture:torture_onoff task: onlining 5
> [ 75.213514] smpboot: Booting Node 0 Processor 5 APIC 0x5
> [ 75.352163] rcu-torture:torture_onoff task: onlined 5
> [ 76.352021] rcu-torture:torture_onoff task: offlining 5
> [ 76.407822] smpboot: CPU 5 is now offline
> [ 76.461629] rcu-torture:torture_onoff task: offlined 5
> [ 77.462018] rcu-torture:torture_onoff task: offlining 3
> [ 77.532054] smpboot: CPU 3 is now offline
> [ 77.586834] rcu-torture:torture_onoff task: offlined 3
> [ 78.587038] rcu-torture:torture_onoff task: onlining 15
> [ 78.660026] smpboot: Booting Node 0 Processor 15 APIC 0xf
> [ 78.710236] rcu-torture:torture_onoff task: onlined 15
> [ 79.710023] rcu-torture:torture_onoff task: onlining 8
> [ 79.764771] smpboot: Booting Node 0 Processor 8 APIC 0x8
> [ 79.816193] rcu-torture:torture_onoff task: onlined 8
> [ 80.817021] rcu-torture:torture_onoff task: offlining 14
> [ 80.889959] smpboot: CPU 14 is now offline
> [ 80.945843] rcu-torture:torture_onoff task: offlined 14
> [ 81.946011] rcu-torture:torture_onoff task: offlining 1
> [ 81.982648] smpboot: CPU 1 is now offline
> [ 82.023787] rcu-torture:torture_onoff task: offlined 1
> [ 83.024014] rcu-torture:torture_onoff task: onlining 2
> [ 83.036513] smpboot: Booting Node 0 Processor 2 APIC 0x2
> [ 83.227164] rcu-torture:torture_onoff task: onlined 2
> [ 84.227012] rcu-torture:torture_onoff task: onlining 14
> [ 84.247776] smpboot: Booting Node 0 Processor 14 APIC 0xe
> [ 84.339163] rcu-torture:torture_onoff task: onlined 14
> [ 85.339012] rcu-torture:torture_onoff task: offlining 8
> [ 85.420802] smpboot: CPU 8 is now offline
> [ 85.442792] rcu-torture:torture_onoff task: offlined 8
> [ 86.443011] rcu-torture:torture_onoff task: offlining 13
> [ 86.497797] smpboot: CPU 13 is now offline
> [ 86.498352] BUG: unable to handle kernel NULL pointer dereference at (null)
> [ 86.499223] IP: [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 86.499255] PGD 0
> [ 86.499255] Oops: 0002 [#1] PREEMPT SMP
> [ 86.499255] Modules linked in:
> [ 86.499255] CPU: 11 PID: 794 Comm: torture_onoff Not tainted 4.5.0-rc1+ #14
> [ 86.499255] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.499255] task: ffff88007c67a580 ti: ffff88007c63c000 task.ti: ffff88007c63c000
> [ 86.499255] RIP: 0010:[<ffffffff810b9452>] [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 86.499255] RSP: 0000:ffff88007c63fc98 EFLAGS: 00010086
> [ 86.499255] RAX: dead000000000200 RBX: ffff88007fb6cc00 RCX: ffff88007fbacc00
> [ 86.499255] RDX: 0000000000000000 RSI: ffff88007fbad650 RDI: ffff88007fb6cc00
> [ 86.499255] RBP: ffff88007c63fcc0 R08: 0000000000000000 R09: ffffffff81e4d360
> [ 86.499255] R10: 0000000000000000 R11: 0000000000018f70 R12: ffff88007fbad650
> [ 86.499255] R13: ffff88007fb6cc00 R14: 000000000000000b R15: ffff88007fbac420
> [ 86.499255] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 86.509030] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.509030] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.509030] Stack:
> [ 86.509030] ffff88007fb6cc00 ffff88007fbad658 ffff88007fbada50 ffff88007fbad850
> [ 86.509030] ffff88007fbad458 ffff88007c63fd08 ffffffff810b95c4 ffff88007fbacc00
> [ 86.509030] ffff88007fbad648 00000000fffffff0 ffffffff81e4e0c0 0000000000000007
> [ 86.509030] Call Trace:
> [ 86.509030] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 86.509030] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 86.509030] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 86.509030] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 86.509030] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 86.509030] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 86.509030] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 86.509030] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.509030] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.509030] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 86.509030] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 86.509030] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 86.509030] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.509030] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.509030] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.509030] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.509030] Code: 56 41 55 41 54 53 48 8b 06 44 8b 77 40 48 85 c0 74 53 49 89 fd 49 89 f4 4d 8b 3c 24 66 66 66 66 90 49 8b 07 49 8b 57 08 48 85 c0 <48> 89 02 74 04 48 89 50 08 48 b8 00 02 00 00 00 00 ad de 4c 89
> [ 86.509030] RIP [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> [ 86.509030] RSP <ffff88007c63fc98>
> [ 86.509030] CR2: 0000000000000000
> [ 86.509030] ---[ end trace 68c18a1de6af7dbc ]---
> [ 86.509030] note: torture_onoff[794] exited with preempt_count 3
> [ 86.530564] BUG: spinlock lockup suspected on CPU#11, torture_onoff/794
> [ 86.530564] lock: 0xffff88007fb6cc00, .magic: dead4ead, .owner: torture_onoff/794, .owner_cpu: 11
> [ 86.530564] CPU: 11 PID: 794 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] ffff88007fb6cc00 ffff88007fb63e50 ffffffff8132cd6c ffff88007c67a580
> [ 86.530564] ffff88007fb63e70 ffffffff81092fb3 ffff88007fb6cc00 00000000cfbb42a0
> [ 86.530564] ffff88007fb63ea0 ffffffff810930db ffff88007fb6cc00 ffffffff81e080c8
> [ 86.530564] Call Trace:
> [ 86.530564] <IRQ> [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 86.530564] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 86.530564] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 86.530564] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 86.530564] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 86.530564] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 86.530564] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 86.530564] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 86.530564] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 86.530564] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 86.530564] <EOI> [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 86.530564] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 86.530564] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 86.530564] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 86.530564] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 86.530564] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 86.530564] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 86.530564] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 86.530564] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 86.530564] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 86.530564] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 86.530564] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 86.530564] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 86.530564] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 86.530564] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 86.530564] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 86.530564] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 86.530564] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 86.530564] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 86.530564] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.530564] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.530564] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 86.530564] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 86.530564] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Sending NMI to all CPUs:
> [ 86.530564] NMI backtrace for cpu 0
> [ 86.530564] CPU: 0 PID: 777 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007c66be80 ti: ffff88007c660000 task.ti: ffff88007c660000
> [ 86.530564] RIP: 0010:[<ffffffff81339455>] [<ffffffff81339455>] delay_tsc+0x25/0xc0
> [ 86.530564] RSP: 0018:ffff88007c663d00 EFLAGS: 00000002
> [ 86.530564] RAX: 00000000f5d32a52 RBX: ffff88007fbacc00 RCX: 0000000000000002
> [ 86.530564] RDX: 00000000000000b0 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 86.530564] RBP: ffff88007c663d20 R08: ffff88007c660000 R09: ffff88007fbacc00
> [ 86.530564] R10: ffff88007c663e30 R11: 0000000000000001 R12: 00000000aaeed6e6
> [ 86.530564] R13: 0000000000000001 R14: 0000000000000000 R15: ffff88007c663dd0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd75020 CR3: 0000000001e0f000 CR4: 00000000000006f0
> [ 86.530564] Stack:
> [ 86.530564] ffff88007fbacc00 00000000aaeed6e6 0000000000000001 00000000cfbb42a0
> [ 86.530564] ffff88007c663d30 ffffffff8133930a ffff88007c663d60 ffffffff810930c7
> [ 86.530564] 0000000000000286 ffff88007fbacc00 ffff88007fbacc00 000000000000cc00
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 86.530564] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 86.530564] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 86.530564] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 86.530564] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 86.530564] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 86.530564] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 5e 41 5f 5d c3 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 <48> c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 43
> [ 86.530564] NMI backtrace for cpu 2
> [ 86.530564] CPU: 2 PID: 787 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007cb24b00 ti: ffff88007c680000 task.ti: ffff88007c680000
> [ 86.530564] RIP: 0010:[<ffffffff81339463>] [<ffffffff81339463>] delay_tsc+0x33/0xc0
> [ 86.530564] RSP: 0018:ffff88007c683db0 EFLAGS: 00000286
> [ 86.530564] RAX: 0000000080000000 RBX: 000000b0f5d35a78 RCX: 0000000000000001
> [ 86.530564] RDX: 0000000080000001 RSI: ffffffff81ca0d44 RDI: 00000000ffffffff
> [ 86.530564] RBP: ffff88007c683dd0 R08: ffff88007c680000 R09: 0000000000000002
> [ 86.530564] R10: 0000000000000000 R11: 0000000000000001 R12: 000000b0f5a85ab0
> [ 86.530564] R13: 0000000000351e94 R14: 0000000000000002 R15: ffffffff820d5fe0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] 0000000000000008 ffff88007c683e20 00000032bf972035 000000000000046f
> [ 86.530564] ffff88007c683de0 ffffffff81339337 ffff88007c683e00 ffffffff810add86
> [ 86.530564] 0000000000000000 0000000000000000 ffff88007c683ea8 ffffffff810ad458
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 86.530564] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 86.530564] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 <bf> 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f
> [ 86.530564] NMI backtrace for cpu 6
> [ 86.530564] CPU: 6 PID: 784 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007cb22580 ti: ffff88007c624000 task.ti: ffff88007c624000
> [ 86.530564] RIP: 0010:[<ffffffff810ad462>] [<ffffffff810ad462>] rcu_torture_reader+0x1b2/0x2e0
> [ 86.530564] RSP: 0018:ffff88007c627e10 EFLAGS: 00000246
> [ 86.530564] RAX: ffff88007cb22580 RBX: 0000000000000000 RCX: 00000000000493e0
> [ 86.530564] RDX: 0000000000000000 RSI: ffff88007fad27d8 RDI: ffffffff810732f6
> [ 86.530564] RBP: ffff88007c627ea8 R08: ffff88007c624000 R09: ffff88007fad53f0
> [ 86.530564] R10: ffff88007c627e30 R11: 000000000000005a R12: 0000000000000000
> [ 86.530564] R13: 00000032c47cf773 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fac0000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] 0000000000000000 0000000081a0a240 41b2bee7f92fd497 0000000000001179
> [ 86.530564] ffff88007cc53d40 ffff88007c50bdf0 00000000fffcd063 ffffffff810ad590
> [ 86.530564] 0000000000000000 ffffffff00000006 00000000ffffffff 0000000000000000
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 00 00 00 41 8b 4f 28 85 c9 75 07 f0 ff 05 13 8a 02 01 48 8b 05 80 89 02 01 48 8d 7c 24 10 ff 50 20 bf 01 00 00 00 e8 4e ac fc ff <4d> 63 67 10 48 8b 05 63 89 02 01 41 83 fc 0a 0f 8e ca fe ff ff
> [ 86.530564] NMI backtrace for cpu 7
> [ 86.530564] CPU: 7 PID: 788 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007cb25780 ti: ffff88007c684000 task.ti: ffff88007c684000
> [ 86.530564] RIP: 0010:[<ffffffff81091ab0>] [<ffffffff81091ab0>] in_lock_functions+0x0/0x20
> [ 86.530564] RSP: 0018:ffff88007c687df0 EFLAGS: 00000246
> [ 86.530564] RAX: ffff88007c687ea8 RBX: ffffffff810732f6 RCX: 00000000000493e0
> [ 86.530564] RDX: 0000000000000000 RSI: ffff88007faf27d8 RDI: ffffffff810732f6
> [ 86.530564] RBP: ffff88007c687e00 R08: ffff88007c684000 R09: ffff88007faf53f0
> [ 86.530564] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
> [ 86.530564] R13: 00000032c47d0479 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] ffffffff81078130 0000000000000000 ffff88007c687ea8 ffffffff810ad462
> [ 86.530564] 0000000000000000 0000000081a0a240 80b0c9268da6f193 0000000000000081
> [ 86.530564] 0000000000000000 ffff88007c623e30 00000000fffcd063 ffffffff810ad590
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff81078130>] ? preempt_count_add+0x80/0xc0
> [ 86.530564] [<ffffffff810ad462>] rcu_torture_reader+0x1b2/0x2e0
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 81 48 c7 c2 1e 0a c9 81 be 4b 00 00 00 48 c7 c7 18 e1 c9 81 e8 d2 56 fc ff eb 80 55 48 89 7f 38 48 89 e5 5d c3 66 0f 1f 44 00 00 <55> 31 c0 48 81 ff c0 3f 8b 81 48 89 e5 72 0c 31 c0 48 81 ff fa
> [ 86.530564] NMI backtrace for cpu 9
> [ 86.530564] CPU: 9 PID: 780 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007c66a580 ti: ffff88007c654000 task.ti: ffff88007c654000
> [ 86.530564] RIP: 0010:[<ffffffff81339463>] [<ffffffff81339463>] delay_tsc+0x33/0xc0
> [ 86.530564] RSP: 0018:ffff88007c657db0 EFLAGS: 00000286
> [ 86.530564] RAX: 0000000080000000 RBX: 000000b0f5d3e3fa RCX: 0000000000000001
> [ 86.530564] RDX: 0000000080000001 RSI: ffffffff81ca0d44 RDI: 00000000ffffffff
> [ 86.530564] RBP: ffff88007c657dd0 R08: ffff88007c654000 R09: ffff88007fb353f0
> [ 86.530564] R10: ffff88007c657e30 R11: 0000000000000078 R12: 000000b0f5b422be
> [ 86.530564] R13: 0000000000351e15 R14: 0000000000000009 R15: ffffffff820d5fe0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fb20000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd5f720 CR3: 000000007b0a0000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] 000000000000001c ffff88007c657e20 00000032c322cb52 000000000000046f
> [ 86.530564] ffff88007c657de0 ffffffff81339337 ffff88007c657e00 ffffffff810add86
> [ 86.530564] 0000000000000000 0000000000000000 ffff88007c657ea8 ffffffff810ad458
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 86.530564] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 86.530564] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 <bf> 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f
> [ 86.530564] NMI backtrace for cpu 10
> [ 86.530564] CPU: 10 PID: 0 Comm: swapper/10 Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007cc98c80 ti: ffff88007cca4000 task.ti: ffff88007cca4000
> [ 86.530564] RIP: 0010:[<ffffffff8133947a>] [<ffffffff8133947a>] delay_tsc+0x4a/0xc0
> [ 86.530564] RSP: 0018:ffff88007fb43d78 EFLAGS: 00000002
> [ 86.530564] RAX: 00000000f5d4115e RBX: ffff88007fb6cc00 RCX: 0000000000000104
> [ 86.530564] RDX: 000000b0f5d4115e RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 86.530564] RBP: ffff88007fb43d98 R08: 0000000000000000 R09: 000000000000dec5
> [ 86.530564] R10: 00000000034dd705 R11: 0000000002f96dbb R12: 000000b0f5d4115e
> [ 86.530564] R13: 0000000000000001 R14: 000000000000000a R15: 0000000000000000
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fb40000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] ffff88007fb6cc00 00000000b85120e5 0000000000000001 00000000cfbb42a0
> [ 86.530564] ffff88007fb43da8 ffffffff8133930a ffff88007fb43dd8 ffffffff810930c7
> [ 86.530564] ffff88007fb6cc00 ffffffff820d8c80 ffff88007fb6cc00 0000000000000000
> [ 86.530564] Call Trace:
> [ 86.530564] <IRQ> d [<ffffffff8133930a>] __delay+0xa/0x10
> [ 86.530564] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 86.530564] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 86.530564] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 86.530564] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 86.530564] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 86.530564] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 86.530564] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 86.530564] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 86.530564] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 86.530564] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 86.530564] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 86.530564] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 86.530564] <EOI> d [<ffffffff8100f303>] ? default_idle+0x13/0xd0
> [ 86.530564] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 86.530564] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 86.530564] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 86.530564] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 86.530564] Code: c6 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f ae e8 <0f> 31 48 c1 e2 20 48 89 d3 48 09 c3 48 89 d8 4c 29 e0 49 39 c5
> [ 86.530564] NMI backtrace for cpu 11
> [ 86.530564] CPU: 11 PID: 794 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007c67a580 ti: ffff88007c63c000 task.ti: ffff88007c63c000
> [ 86.530564] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 86.530564] RSP: 0000:ffff88007fb63dd0 EFLAGS: 00000046
> [ 86.530564] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 000000000000000b
> [ 86.530564] RDX: 000000000000000b RSI: 0000000000000010 RDI: 0000000000000300
> [ 86.530564] RBP: ffff88007fb63e08 R08: 0000000000000000 R09: 000000000000dec5
> [ 86.530564] R10: ffff88007c63ff58 R11: 00000000000002cd R12: ffffffff81f31740
> [ 86.530564] R13: 0000000000000400 R14: 0000000000000002 R15: 000000000000000b
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] 0000000000000082 0000000b7fb63de0 000000000000ff40 0000000000000001
> [ 86.530564] ffffffff8103fd20 00000000cfbb42a0 0000000000000000 ffff88007fb63e18
> [ 86.530564] ffffffff8103fd36 ffff88007fb63e60 ffffffff81331299 ffffffff81008b50
> [ 86.530564] Call Trace:
> [ 86.530564] <IRQ> d [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 86.530564] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 86.530564] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 86.530564] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 86.530564] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 86.530564] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 86.530564] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 86.530564] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 86.530564] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 86.530564] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 86.530564] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 86.530564] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 86.530564] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 86.530564] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 86.530564] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 86.530564] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 86.530564] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 86.530564] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 86.530564] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 86.530564] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 86.530564] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 86.530564] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 86.530564] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 86.530564] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 86.530564] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 86.530564] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 86.530564] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 86.530564] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 86.530564] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 86.530564] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 86.530564] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 86.530564] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 86.530564] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.530564] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.530564] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 86.530564] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 86.530564] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 86.530564] NMI backtrace for cpu 12
> [ 86.530564] CPU: 12 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007cb27080 ti: ffff88007c674000 task.ti: ffff88007c674000
> [ 86.530564] RIP: 0010:[<ffffffff81339453>] [<ffffffff81339453>] delay_tsc+0x23/0xc0
> [ 86.530564] RSP: 0000:ffff88007c677d00 EFLAGS: 00000002
> [ 86.530564] RAX: 000000000000000c RBX: ffff88007fb6cc00 RCX: 0000000000000002
> [ 86.530564] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 86.530564] RBP: ffff88007c677d20 R08: ffff88007c674000 R09: ffff88007fb6cc00
> [ 86.530564] R10: ffff88007c677e30 R11: 000000000000002d R12: 00000000ab555708
> [ 86.530564] R13: 0000000000000001 R14: 000000000000000c R15: ffff88007c677dd0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] ffff88007fb6cc00 00000000ab555708 0000000000000001 00000000cfbb42a0
> [ 86.530564] ffff88007c677d30 ffffffff8133930a ffff88007c677d60 ffffffff810930c7
> [ 86.530564] 0000000000000286 ffff88007fb6cc00 ffff88007fb6cc00 000000000000cc00
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 86.530564] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 86.530564] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 86.530564] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 86.530564] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 86.530564] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 86.530564] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 5d 41 5e 41 5f 5d c3 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 <0f> 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00
> [ 86.530564] NMI backtrace for cpu 14
> [ 86.530564] CPU: 14 PID: 789 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007cb26400 ti: ffff88007c670000 task.ti: ffff88007c670000
> [ 86.530564] RIP: 0010:[<ffffffff810acb70>] [<ffffffff810acb70>] rcu_torture_read_lock+0x0/0x10
> [ 86.530564] RSP: 0018:ffff88007c673e08 EFLAGS: 00000286
> [ 86.530564] RAX: ffffffff81e47800 RBX: 0000000000000000 RCX: 0000000000000001
> [ 86.530564] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff81c9f0eb
> [ 86.530564] RBP: ffff88007c673ea8 R08: ffff88007c670000 R09: 0000000000000002
> [ 86.530564] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
> [ 86.530564] R13: 00000032c47e38a4 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] ffffffff810ad405 0000000000000000 0000000000015380 c7b7bbe7a8e3038e
> [ 86.530564] 0000000000000b1c ffff88007cbbbe30 ffff88007c5f3e30 00000000fffcd063
> [ 86.530564] ffffffff810ad590 0000000000000000 ffffffff0000000e 00000000ffffffff
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff810ad405>] ? rcu_torture_reader+0x155/0x2e0
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: 48 8d 3c 13 48 8b 0c 11 48 8b 14 37 89 c6 48 c7 c7 4c f0 c9 81 e8 70 ac 07 00 eb 94 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 <55> 48 89 e5 e8 47 b1 ff ff 31 c0 5d c3 0f 1f 00 80 3d e1 ad d9
> [ 86.530564] NMI backtrace for cpu 15
> [ 86.530564] CPU: 15 PID: 778 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.530564] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.530564] task: ffff88007c66d780 ti: ffff88007c664000 task.ti: ffff88007c664000
> [ 86.530564] RIP: 0010:[<ffffffff810addac>] [<ffffffff810addac>] rcu_read_delay+0x5c/0xb0
> [ 86.530564] RSP: 0018:ffff88007c667df0 EFLAGS: 00000202
> [ 86.530564] RAX: 00000000000970a2 RBX: 0000000000000000 RCX: 0000000000001770
> [ 86.530564] RDX: 000000000000087c RSI: ffff88007fbf27d8 RDI: ffff88007c667e20
> [ 86.530564] RBP: ffff88007c667e00 R08: ffff88007c664000 R09: ffff88007fbf53f0
> [ 86.530564] R10: ffff88007c667e30 R11: 0000000000000001 R12: ffff88007c667e20
> [ 86.530564] R13: 00000032c47e463e R14: 000000000000046f R15: ffffffff820d5fe0
> [ 86.530564] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 86.530564] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.530564] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.530564] Stack:
> [ 86.530564] 0000000000000000 0000000000000000 ffff88007c667ea8 ffffffff810ad458
> [ 86.530564] 0000000000000000 0000000081a0a240 7de1a6dcdd5cdd3f 000000000000140e
> [ 86.530564] ffff88007c5e3de0 ffff88007fbecf60 00000000fffcd063 ffffffff810ad590
> [ 86.530564] Call Trace:
> [ 86.530564] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 86.530564] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.530564] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.530564] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.530564] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.530564] Code: e8 8a b5 28 00 48 83 eb 01 75 f0 4c 89 e7 e8 6c 83 07 00 48 63 15 d9 94 02 01 48 8d 14 92 48 8d 0c 92 31 d2 48 c1 e1 04 48 f7 f1 <48> 85 d2 74 3c 65 8b 05 d8 cf f5 7e a9 ff ff ff 7f 74 05 5b 41
> [ 86.637011] BUG: spinlock lockup suspected on CPU#10, swapper/10/0
> [ 86.637011] lock: 0xffff88007fb6cc00, .magic: dead4ead, .owner: torture_onoff/794, .owner_cpu: 11
> [ 86.637011] CPU: 10 PID: 0 Comm: swapper/10 Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] ffff88007fb6cc00 ffff88007fb43d88 ffffffff8132cd6c ffff88007c67a580
> [ 86.637011] ffff88007fb43da8 ffffffff81092fb3 ffff88007fb6cc00 00000000cfbb42a0
> [ 86.637011] ffff88007fb43dd8 ffffffff810930db ffff88007fb6cc00 ffffffff820d8c80
> [ 86.637011] Call Trace:
> [ 86.637011] <IRQ> [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 86.637011] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 86.637011] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 86.637011] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 86.637011] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 86.637011] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 86.637011] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 86.637011] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 86.637011] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 86.637011] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 86.637011] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 86.637011] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 86.637011] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 86.637011] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 86.637011] <EOI> [<ffffffff8100f303>] ? default_idle+0x13/0xd0
> [ 86.637011] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 86.637011] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 86.637011] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 86.637011] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 86.637011] Sending NMI to all CPUs:
> [ 86.637011] NMI backtrace for cpu 0
> [ 86.637011] CPU: 0 PID: 777 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007c66be80 ti: ffff88007c660000 task.ti: ffff88007c660000
> [ 86.637011] RIP: 0010:[<ffffffff81339453>] [<ffffffff81339453>] delay_tsc+0x23/0xc0
> [ 86.637011] RSP: 0018:ffff88007c663d00 EFLAGS: 00000002
> [ 86.637011] RAX: 0000000000000000 RBX: ffff88007fbacc00 RCX: 0000000000000002
> [ 86.637011] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 86.637011] RBP: ffff88007c663d20 R08: ffff88007c660000 R09: ffff88007fbacc00
> [ 86.637011] R10: ffff88007c663e30 R11: 0000000000000001 R12: 00000000bfcdebc0
> [ 86.637011] R13: 0000000000000001 R14: 0000000000000000 R15: ffff88007c663dd0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd75020 CR3: 0000000001e0f000 CR4: 00000000000006f0
> [ 86.637011] Stack:
> [ 86.637011] ffff88007fbacc00 00000000bfcdebc0 0000000000000001 00000000cfbb42a0
> [ 86.637011] ffff88007c663d30 ffffffff8133930a ffff88007c663d60 ffffffff810930c7
> [ 86.637011] 0000000000000286 ffff88007fbacc00 ffff88007fbacc00 000000000000cc00
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 86.637011] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 86.637011] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 86.637011] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 86.637011] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 86.637011] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 86.637011] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: 5d 41 5e 41 5f 5d c3 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 <0f> 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00
> [ 86.637011] NMI backtrace for cpu 2
> [ 86.637011] CPU: 2 PID: 787 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007cb24b00 ti: ffff88007c680000 task.ti: ffff88007c680000
> [ 86.637011] RIP: 0010:[<ffffffff810780b0>] [<ffffffff810780b0>] preempt_count_add+0x0/0xc0
> [ 86.637011] RSP: 0018:ffff88007c683da8 EFLAGS: 00000286
> [ 86.637011] RAX: 0000000080000000 RBX: 000000bbab34b2ec RCX: 0000000000000001
> [ 86.637011] RDX: 0000000080000001 RSI: ffffffff81ca0d44 RDI: 0000000000000001
> [ 86.637011] RBP: ffff88007c683dd0 R08: ffff88007c680000 R09: ffff88007fa553f0
> [ 86.637011] R10: 0000000000000000 R11: 0000000000000001 R12: 000000bbab1b5ef0
> [ 86.637011] R13: 0000000000351e94 R14: 0000000000000002 R15: ffffffff820d5fe0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] ffffffff8133946d 0000000000000006 ffff88007c683e20 00000035d5ff8437
> [ 86.637011] 000000000000046f ffff88007c683de0 ffffffff81339337 ffff88007c683e00
> [ 86.637011] ffffffff810add86 0000000000000000 0000000000000000 ffff88007c683ea8
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff8133946d>] ? delay_tsc+0x3d/0xc0
> [ 86.637011] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 86.637011] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 86.637011] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: 3d ba b3 e9 00 00 75 b4 be 44 01 00 00 48 c7 c7 fb dd c9 81 e8 72 f1 fd ff c6 05 a0 b3 e9 00 01 eb 9a 66 0f 1f 84 00 00 00 00 00 <8b> 15 02 a7 01 01 55 65 01 3d d2 2c f9 7e 48 89 e5 53 89 fb 85
> [ 86.637011] NMI backtrace for cpu 6
> [ 86.637011] CPU: 6 PID: 784 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007cb22580 ti: ffff88007c624000 task.ti: ffff88007c624000
> [ 86.637011] RIP: 0010:[<ffffffff810addac>] [<ffffffff810addac>] rcu_read_delay+0x5c/0xb0
> [ 86.637011] RSP: 0018:ffff88007c627df0 EFLAGS: 00000202
> [ 86.637011] RAX: 000000000005640c RBX: 0000000000000000 RCX: 0000000000001770
> [ 86.637011] RDX: 0000000000000b4f RSI: ffff88007fad27d8 RDI: ffff88007c627e20
> [ 86.637011] RBP: ffff88007c627e00 R08: ffff88007c624000 R09: ffff88007fad53f0
> [ 86.637011] R10: ffff88007c627e30 R11: 000000000000005a R12: ffff88007c627e20
> [ 86.637011] R13: 00000035db3bb386 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fac0000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] 0000000000000000 0000000000000000 ffff88007c627ea8 ffffffff810ad458
> [ 86.637011] 0000000000000000 0000000081a0a240 770957c6e48f7e58 00000000000011d6
> [ 86.637011] ffff88007cc53d40 ffff88007c50bdf0 00000000fffcd063 ffffffff810ad590
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: e8 8a b5 28 00 48 83 eb 01 75 f0 4c 89 e7 e8 6c 83 07 00 48 63 15 d9 94 02 01 48 8d 14 92 48 8d 0c 92 31 d2 48 c1 e1 04 48 f7 f1 <48> 85 d2 74 3c 65 8b 05 d8 cf f5 7e a9 ff ff ff 7f 74 05 5b 41
> [ 86.637011] NMI backtrace for cpu 7
> [ 86.637011] CPU: 7 PID: 783 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007cb21900 ti: ffff88007c620000 task.ti: ffff88007c620000
> [ 86.637011] RIP: 0010:[<ffffffff81347fe8>] [<ffffffff81347fe8>] check_preemption_disabled+0x8/0xe0
> [ 86.637011] RSP: 0018:ffff88007c623d90 EFLAGS: 00000246
> [ 86.637011] RAX: 0000000080000001 RBX: 000000bbab350fbc RCX: 0000000000000001
> [ 86.637011] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 86.637011] RBP: ffff88007c623da0 R08: ffff88007c620000 R09: 0000000000000002
> [ 86.637011] R10: 0000000000000000 R11: 0000000000000001 R12: 000000bbab33726c
> [ 86.637011] R13: 00000000000a9fc1 R14: 0000000000000007 R15: ffffffff820d5fe0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] ffff88007c623da0 ffffffff813480d7 ffff88007c623dd0 ffffffff81339472
> [ 86.637011] 0000000000000000 ffff88007c623e20 00000035db3b4939 000000000000046f
> [ 86.637011] ffff88007c623de0 ffffffff81339337 ffff88007c623e00 ffffffff810addf7
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 86.637011] [<ffffffff81339472>] delay_tsc+0x42/0xc0
> [ 86.637011] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 86.637011] [<ffffffff810addf7>] rcu_read_delay+0xa7/0xb0
> [ 86.637011] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: 40 08 00 00 00 00 e9 1b ff ff ff 4d 89 e7 4c 8b 6d c8 49 83 cf 01 e9 0b ff ff ff 0f 1f 84 00 00 00 00 00 55 65 8b 05 a8 2d cc 7e <48> 89 e5 41 56 41 55 41 54 53 65 8b 1d 27 21 cc 7e a9 ff ff ff
> [ 86.637011] NMI backtrace for cpu 9
> [ 86.637011] CPU: 9 PID: 780 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007c66a580 ti: ffff88007c654000 task.ti: ffff88007c654000
> [ 86.637011] RIP: 0010:[<ffffffff810ad367>] [<ffffffff810ad367>] rcu_torture_reader+0xb7/0x2e0
> [ 86.637011] RSP: 0018:ffff88007c657e10 EFLAGS: 00000202
> [ 86.637011] RAX: ffffffff81e47800 RBX: ffffffffffffffff RCX: 00000000000493e0
> [ 86.637011] RDX: 0000000000000000 RSI: ffffffff81d29759 RDI: ffffffff81cbdff8
> [ 86.637011] RBP: ffff88007c657ea8 R08: ffff88007c654000 R09: ffff88007fb353f0
> [ 86.637011] R10: ffff88007c657e30 R11: 0000000000000078 R12: 0000000000000000
> [ 86.637011] R13: 00000035db3bcddb R14: 000000000000046f R15: ffffffff820d5fe0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fb20000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd5f720 CR3: 000000007b0a0000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] 0000000000000000 0000000081a0a240 65698c08e52fd545 0000000000000aad
> [ 86.637011] 0000000000000000 ffff88007fb2cf60 00000000fffcd063 ffffffff810ad590
> [ 86.637011] 0000000000000000 ffffffff00000009 00000000ffffffff 0000000000000000
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: e9 9a 00 00 00 ff 50 38 41 83 fc 01 48 89 c3 0f 8f 32 01 00 00 48 c7 c7 59 97 d2 81 4c 29 f3 e8 80 ad 29 00 48 8b 05 69 8a 02 01 <48> c7 c7 59 97 d2 81 65 4a ff 04 e5 40 cb 00 00 48 83 78 30 01
> [ 86.637011] NMI backtrace for cpu 10
> [ 86.637011] CPU: 10 PID: 0 Comm: swapper/10 Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007cc98c80 ti: ffff88007cca4000 task.ti: ffff88007cca4000
> [ 86.637011] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 86.637011] RSP: 0018:ffff88007fb43d08 EFLAGS: 00000046
> [ 86.637011] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 000000000000000a
> [ 86.637011] RDX: 000000000000000a RSI: 0000000000000010 RDI: 0000000000000300
> [ 86.637011] RBP: ffff88007fb43d40 R08: 0000000000000000 R09: 000000000000dec5
> [ 86.637011] R10: ffff88007cca7f58 R11: 0000000000000434 R12: ffffffff81f31740
> [ 86.637011] R13: 0000000000000400 R14: 0000000000000002 R15: 000000000000000a
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fb40000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] 0000000000000082 0000000a7fb43d18 000000000000ff40 0000000000000001
> [ 86.637011] ffffffff8103fd20 00000000cfbb42a0 0000000000000000 ffff88007fb43d50
> [ 86.637011] ffffffff8103fd36 ffff88007fb43d98 ffffffff81331299 ffffffff81008b50
> [ 86.637011] Call Trace:
> [ 86.637011] <IRQ> d [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 86.637011] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 86.637011] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 86.637011] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 86.637011] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 86.637011] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 86.637011] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 86.637011] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 86.637011] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 86.637011] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 86.637011] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 86.637011] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 86.637011] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 86.637011] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 86.637011] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 86.637011] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 86.637011] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 86.637011] <EOI> d [<ffffffff8100f303>] ? default_idle+0x13/0xd0
> [ 86.637011] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 86.637011] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 86.637011] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 86.637011] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 86.637011] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 86.637011] NMI backtrace for cpu 11
> [ 86.637011] CPU: 11 PID: 794 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007c67a580 ti: ffff88007c63c000 task.ti: ffff88007c63c000
> [ 86.637011] RIP: 0010:[<ffffffff810920b1>] [<ffffffff810920b1>] queued_spin_lock_slowpath+0x171/0x1a0
> [ 86.637011] RSP: 0000:ffff88007fb63e58 EFLAGS: 00000002
> [ 86.637011] RAX: 0000000000000101 RBX: ffff88007fb6cc00 RCX: 0000000000000001
> [ 86.637011] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 86.637011] RBP: ffff88007fb63e70 R08: 00000000000006e7 R09: 0000000000000418
> [ 86.637011] R10: ffff88007c63ff58 R11: 0000000000000418 R12: 00000000cfbb42a0
> [ 86.637011] R13: 0000000000000001 R14: 00000000cfbb42a0 R15: 0000000000000000
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] ffff88007fb6cc00 00000000cfbb42a0 0000000000000001 ffff88007fb63ea0
> [ 86.637011] ffffffff81093185 ffff88007fb6cc00 ffffffff81e080c8 0000000000000001
> [ 86.637011] 0000000000000001 ffff88007fb63eb8 ffffffff818b3ffb ffff88007fb6cc00
> [ 86.637011] Call Trace:
> [ 86.637011] <IRQ> d [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 86.637011] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 86.637011] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 86.637011] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 86.637011] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 86.637011] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 86.637011] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 86.637011] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 86.637011] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 86.637011] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 86.637011] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 86.637011] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 86.637011] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 86.637011] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 86.637011] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 86.637011] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 86.637011] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 86.637011] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 86.637011] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 86.637011] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 86.637011] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 86.637011] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 86.637011] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 86.637011] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 86.637011] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 86.637011] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 86.637011] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 86.637011] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.637011] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 86.637011] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 86.637011] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 86.637011] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 8b 03 <84> c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3 f3 90
> [ 86.637011] NMI backtrace for cpu 12
> [ 86.637011] CPU: 12 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007cb27080 ti: ffff88007c674000 task.ti: ffff88007c674000
> [ 86.637011] RIP: 0010:[<ffffffff81339453>] [<ffffffff81339453>] delay_tsc+0x23/0xc0
> [ 86.637011] RSP: 0000:ffff88007c677d00 EFLAGS: 00000002
> [ 86.637011] RAX: 000000000000000c RBX: ffff88007fb6cc00 RCX: 0000000000000002
> [ 86.637011] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 86.637011] RBP: ffff88007c677d20 R08: ffff88007c674000 R09: ffff88007fb6cc00
> [ 86.637011] R10: ffff88007c677e30 R11: 000000000000002d R12: 00000000bc78e940
> [ 86.637011] R13: 0000000000000001 R14: 000000000000000c R15: ffff88007c677dd0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] ffff88007fb6cc00 00000000bc78e940 0000000000000001 00000000cfbb42a0
> [ 86.637011] ffff88007c677d30 ffffffff8133930a ffff88007c677d60 ffffffff810930c7
> [ 86.637011] 0000000000000286 ffff88007fb6cc00 ffff88007fb6cc00 000000000000cc00
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 86.637011] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 86.637011] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 86.637011] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 86.637011] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 86.637011] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 86.637011] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: 5d 41 5e 41 5f 5d c3 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 <0f> 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00
> [ 86.637011] NMI backtrace for cpu 14
> [ 86.637011] CPU: 14 PID: 781 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007cb20000 ti: ffff88007c5f0000 task.ti: ffff88007c5f0000
> [ 86.637011] RIP: 0010:[<ffffffff8133947c>] [<ffffffff8133947c>] delay_tsc+0x4c/0xc0
> [ 86.637011] RSP: 0018:ffff88007c5f3db0 EFLAGS: 00000246
> [ 86.637011] RAX: 00000000ab382c5e RBX: 000000bbab382bb2 RCX: 0000000000000001
> [ 86.637011] RDX: 00000000000000bb RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 86.637011] RBP: ffff88007c5f3dd0 R08: ffff88007c5f0000 R09: 0000000000000002
> [ 86.637011] R10: 0000000000000000 R11: 0000000000000001 R12: 000000bbab1b3e52
> [ 86.637011] R13: 0000000000352dff R14: 000000000000000e R15: ffffffff820d5fe0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] 000000000000000a ffff88007c5f3e20 00000035d411b4b5 000000000000046f
> [ 86.637011] ffff88007c5f3de0 ffffffff81339337 ffff88007c5f3e00 ffffffff810add86
> [ 86.637011] 0000000000000000 0000000000000000 ffff88007c5f3ea8 ffffffff810ad458
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 86.637011] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 86.637011] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f ae e8 0f 31 <48> c1 e2 20 48 89 d3 48 09 c3 48 89 d8 4c 29 e0 49 39 c5 76 24
> [ 86.637011] NMI backtrace for cpu 15
> [ 86.637011] CPU: 15 PID: 778 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 86.637011] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 86.637011] task: ffff88007c66d780 ti: ffff88007c664000 task.ti: ffff88007c664000
> [ 86.637011] RIP: 0010:[<ffffffff81347fe1>] [<ffffffff81347fe1>] check_preemption_disabled+0x1/0xe0
> [ 86.637011] RSP: 0018:ffff88007c667df0 EFLAGS: 00000246
> [ 86.637011] RAX: ffffffff81e47800 RBX: 0000000000000000 RCX: 00000000000493e0
> [ 86.637011] RDX: 0000000000000000 RSI: ffffffff81d29759 RDI: ffffffff81cbdff8
> [ 86.637011] RBP: ffff88007c667e00 R08: ffff88007c664000 R09: ffff88007fbf53f0
> [ 86.637011] R10: ffff88007c667e30 R11: 0000000000000001 R12: 0000000000000000
> [ 86.637011] R13: 00000035db3cb383 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 86.637011] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 86.637011] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 86.637011] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 86.637011] Stack:
> [ 86.637011] ffff88007c667e00 ffffffff813480f3 ffff88007c667ea8 ffffffff810ad385
> [ 86.637011] 0000000000000000 0000000081a0a240 294a84bcaaa92a92 0000000000000890
> [ 86.637011] ffff88007c5e3de0 ffff88007fbecf60 00000000fffcd063 ffffffff810ad590
> [ 86.637011] Call Trace:
> [ 86.637011] [<ffffffff813480f3>] ? __this_cpu_preempt_check+0x13/0x20
> [ 86.637011] [<ffffffff810ad385>] rcu_torture_reader+0xd5/0x2e0
> [ 86.637011] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 86.637011] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 86.637011] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 86.637011] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 86.637011] Code: 00 00 00 49 89 f7 c7 40 08 00 00 00 00 e9 1b ff ff ff 4d 89 e7 4c 8b 6d c8 49 83 cf 01 e9 0b ff ff ff 0f 1f 84 00 00 00 00 00 55 <65> 8b 05 a8 2d cc 7e 48 89 e5 41 56 41 55 41 54 53 65 8b 1d 27
> [ 91.202005] BUG: spinlock lockup suspected on CPU#0, rcu_torture_rea/777
> [ 91.202005] lock: 0xffff88007fbacc00, .magic: dead4ead, .owner: torture_onoff/794, .owner_cpu: 11
> [ 91.202005] CPU: 0 PID: 777 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] ffff88007fbacc00 ffff88007c663d10 ffffffff8132cd6c ffff88007c67a580
> [ 91.202005] ffff88007c663d30 ffffffff81092fb3 ffff88007fbacc00 00000000cfbb42a0
> [ 91.202005] ffff88007c663d60 ffffffff810930db 0000000000000286 ffff88007fbacc00
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 91.202005] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 91.202005] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 91.202005] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 91.202005] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 91.202005] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 91.202005] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 91.202005] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Sending NMI to all CPUs:
> [ 91.202005] NMI backtrace for cpu 0
> [ 91.202005] CPU: 0 PID: 777 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007c66be80 ti: ffff88007c660000 task.ti: ffff88007c660000
> [ 91.202005] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 91.202005] RSP: 0018:ffff88007c663c90 EFLAGS: 00000046
> [ 91.202005] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 0000000000000000
> [ 91.202005] RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000000000000300
> [ 91.202005] RBP: ffff88007c663cc8 R08: 0000000000000000 R09: 000000000000dec5
> [ 91.202005] R10: ffff88007c663f58 R11: 000000000000059a R12: ffffffff81f31740
> [ 91.202005] R13: 0000000000000400 R14: 0000000000000002 R15: 0000000000000000
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd75020 CR3: 0000000001e0f000 CR4: 00000000000006f0
> [ 91.202005] Stack:
> [ 91.202005] 0000000000000086 000000007c663ca0 000000000000ff40 0000000000000001
> [ 91.202005] ffffffff8103fd20 00000000cfbb42a0 ffff88007c663dd0 ffff88007c663cd8
> [ 91.202005] ffffffff8103fd36 ffff88007c663d20 ffffffff81331299 ffffffff81008b50
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 91.202005] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 91.202005] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 91.202005] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 91.202005] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 91.202005] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 91.202005] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 91.202005] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 91.202005] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 91.202005] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 91.202005] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 91.202005] NMI backtrace for cpu 2
> [ 91.202005] CPU: 2 PID: 787 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007cb24b00 ti: ffff88007c680000 task.ti: ffff88007c680000
> [ 91.202005] RIP: 0010:[<ffffffff8112610e>] [<ffffffff8112610e>] torture_random+0xe/0x50
> [ 91.202005] RSP: 0018:ffff88007c683de8 EFLAGS: 00000a03
> [ 91.202005] RAX: 5a933880b777f184 RBX: 0000000000000000 RCX: 0000000000000001
> [ 91.202005] RDX: 0000000000000000 RSI: ffff88007fa527d8 RDI: ffff88007c683e20
> [ 91.202005] RBP: ffff88007c683e00 R08: ffff88007c680000 R09: 0000000000000002
> [ 91.202005] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88007c683e20
> [ 91.202005] R13: 00000037e5c0c22c R14: 000000000000046f R15: ffffffff820d5fe0
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] ffffffff810add5f 0000000000000000 0000000000000000 ffff88007c683ea8
> [ 91.202005] ffffffff810ad458 0000000000000000 0000000081a0a240 eecf9ea3d6081d84
> [ 91.202005] 0000000000001e73 ffff88007c5e7e30 ffff88007fa4cf60 00000000fffcd063
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff810add5f>] ? rcu_read_delay+0xf/0xb0
> [ 91.202005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: b2 fd 00 48 c7 c7 69 ef c9 81 e8 dd 16 00 00 48 8b 03 eb d5 66 0f 1f 84 00 00 00 00 00 48 83 6f 08 01 78 14 48 69 07 01 15 61 02 <48> 05 65 fc 8c 1c 48 89 07 c1 c0 10 c3 55 48 89 e5 53 48 89 fb
> [ 91.202005] NMI backtrace for cpu 6
> [ 91.202005] CPU: 6 PID: 784 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007cb22580 ti: ffff88007c624000 task.ti: ffff88007c624000
> [ 91.202005] RIP: 0010:[<ffffffff810ad39b>] [<ffffffff810ad39b>] rcu_torture_reader+0xeb/0x2e0
> [ 91.202005] RSP: 0018:ffff88007c627e10 EFLAGS: 00000207
> [ 91.202005] RAX: 000000000000000a RBX: 0000000000000000 RCX: 00000000000493e0
> [ 91.202005] RDX: 0000000000000000 RSI: ffffffff81d29759 RDI: ffffffff81cbdff8
> [ 91.202005] RBP: ffff88007c627ea8 R08: ffff88007c624000 R09: ffff88007fad53f0
> [ 91.202005] R10: ffff88007c627e30 R11: 000000000000005a R12: 0000000000000000
> [ 91.202005] R13: 00000037e5c0cf9a R14: 000000000000046f R15: ffffffff820d5fe0
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fac0000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] 0000000000000000 0000000081a0a240 cbee22ce8ab059c0 0000000000001190
> [ 91.202005] ffff88007cc53d40 ffff88007c50bdf0 00000000fffcd063 ffffffff810ad590
> [ 91.202005] 0000000000000000 ffffffff00000006 00000000ffffffff 0000000000000000
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: ff 04 e5 40 cb 00 00 48 83 78 30 01 48 83 db ff e8 5b ad 29 00 48 83 fb 0a b8 0a 00 00 00 48 0f 47 d8 65 48 ff 04 dd e0 ca 00 00 <bf> 01 00 00 00 e8 ab ab fc ff 65 8b 05 e4 d9 f5 7e 85 c0 0f 84
> [ 91.202005] NMI backtrace for cpu 7
> [ 91.202005] CPU: 7 PID: 783 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007cb21900 ti: ffff88007c620000 task.ti: ffff88007c620000
> [ 91.202005] RIP: 0010:[<ffffffff81339463>] [<ffffffff81339463>] delay_tsc+0x33/0xc0
> [ 91.202005] RSP: 0018:ffff88007c623db0 EFLAGS: 00000286
> [ 91.202005] RAX: 0000000080000000 RBX: 000000c2beb23b20 RCX: 0000000000000001
> [ 91.202005] RDX: 0000000080000001 RSI: ffffffff81ca0d44 RDI: 00000000ffffffff
> [ 91.202005] RBP: ffff88007c623dd0 R08: ffff88007c620000 R09: ffff88007faf53f0
> [ 91.202005] R10: 0000000000000000 R11: 0000000000000001 R12: 000000c2beb06098
> [ 91.202005] R13: 0000000000351ec1 R14: 0000000000000007 R15: ffffffff820d5fe0
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] 0000000000000028 ffff88007c623e20 00000037e496c4c4 000000000000046f
> [ 91.202005] ffff88007c623de0 ffffffff81339337 ffff88007c623e00 ffffffff810add86
> [ 91.202005] 0000000000000000 0000000000000000 ffff88007c623ea8 ffffffff810ad458
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 91.202005] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 91.202005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 <bf> 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f
> [ 91.202005] NMI backtrace for cpu 9
> [ 91.202005] CPU: 9 PID: 780 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007c66a580 ti: ffff88007c654000 task.ti: ffff88007c654000
> [ 91.202005] RIP: 0010:[<ffffffff810addde>] [<ffffffff810addde>] rcu_read_delay+0x8e/0xb0
> [ 91.202005] RSP: 0018:ffff88007c657df0 EFLAGS: 00000246
> [ 91.202005] RAX: 0000000000003642 RBX: 0000000000000000 RCX: 00000000000493e0
> [ 91.202005] RDX: 000000000003761e RSI: ffff88007fb327d8 RDI: ffff88007c657e20
> [ 91.202005] RBP: ffff88007c657e00 R08: ffff88007c654000 R09: ffff88007fb353f0
> [ 91.202005] R10: ffff88007c657e30 R11: 0000000000000078 R12: ffff88007c657e20
> [ 91.202005] R13: 00000037e5c0ea8d R14: 000000000000046f R15: ffffffff820d5fe0
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fb20000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd5f720 CR3: 000000007b0a0000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] 0000000000000000 0000000000000000 ffff88007c657ea8 ffffffff810ad458
> [ 91.202005] 0000000000000000 0000000081a0a240 27e1079dd5def862 0000000000000363
> [ 91.202005] 0000000000000000 ffff88007fb2cf60 00000000fffcd063 ffffffff810ad590
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: 05 d8 cf f5 7e a9 ff ff ff 7f 74 05 5b 41 5c 5d c3 4c 89 e7 e8 34 83 07 00 69 0d 9e 94 02 01 20 4e 00 00 31 d2 48 63 c9 48 f7 f1 <48> 85 d2 75 dc e8 28 1b 80 00 5b 41 5c 5d c3 bf 78 1b 0d 00 e8
> [ 91.202005] NMI backtrace for cpu 10
> [ 91.202005] CPU: 10 PID: 0 Comm: swapper/10 Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007cc98c80 ti: ffff88007cca4000 task.ti: ffff88007cca4000
> [ 91.202005] RIP: 0010:[<ffffffff81092067>] [<ffffffff81092067>] queued_spin_lock_slowpath+0x127/0x1a0
> [ 91.202005] RSP: 0018:ffff88007fb43d90 EFLAGS: 00000002
> [ 91.202005] RAX: 0000000000000000 RBX: ffff88007fb6cc00 RCX: ffff88007fb55e80
> [ 91.202005] RDX: 00000000002c0101 RSI: ffffffff81ca0d44 RDI: 00000000002c0000
> [ 91.202005] RBP: ffff88007fb43da8 R08: 0000000000000000 R09: 0000000000000583
> [ 91.202005] R10: ffff88007cca7f58 R11: 0000000000000583 R12: 0000000000000000
> [ 91.202005] R13: ffff88007fb55e80 R14: 00000000cfbb42a0 R15: 0000000000000000
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fb40000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] ffff88007fb6cc00 00000000cfbb42a0 0000000000000001 ffff88007fb43dd8
> [ 91.202005] ffffffff81093185 ffff88007fb6cc00 ffffffff820d8c80 ffff88007fb6cc00
> [ 91.202005] 0000000000000000 ffff88007fb43df0 ffffffff818b3fda 000000000000000b
> [ 91.202005] Call Trace:
> [ 91.202005] <IRQ> d [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 91.202005] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 91.202005] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 91.202005] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 91.202005] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 91.202005] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 91.202005] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 91.202005] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 91.202005] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 91.202005] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 91.202005] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 91.202005] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 91.202005] <EOI> d [<ffffffff8100f303>] ? default_idle+0x13/0xd0
> [ 91.202005] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 91.202005] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 91.202005] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 91.202005] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 91.202005] Code: 48 03 14 c5 20 f5 f2 81 48 89 0a 8b 41 08 85 c0 75 09 f3 90 8b 41 08 85 c0 74 f7 4c 8b 01 4d 85 c0 74 08 41 0f 18 08 eb 02 f3 90 <8b> 13 66 85 d2 75 f7 be 01 00 00 00 eb 10 89 d0 f0 0f b1 33 39
> [ 91.202005] NMI backtrace for cpu 11
> [ 91.202005] CPU: 11 PID: 794 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007c67a580 ti: ffff88007c63c000 task.ti: ffff88007c63c000
> [ 91.202005] RIP: 0010:[<ffffffff810920af>] [<ffffffff810920af>] queued_spin_lock_slowpath+0x16f/0x1a0
> [ 91.202005] RSP: 0000:ffff88007fb63e58 EFLAGS: 00000002
> [ 91.202005] RAX: 00000000002c0101 RBX: ffff88007fb6cc00 RCX: 0000000000000001
> [ 91.202005] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 91.202005] RBP: ffff88007fb63e70 R08: 00000000000006e7 R09: 0000000000000418
> [ 91.202005] R10: ffff88007c63ff58 R11: 0000000000000418 R12: 00000000cfbb42a0
> [ 91.202005] R13: 0000000000000001 R14: 00000000cfbb42a0 R15: 0000000000000000
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] ffff88007fb6cc00 00000000cfbb42a0 0000000000000001 ffff88007fb63ea0
> [ 91.202005] ffffffff81093185 ffff88007fb6cc00 ffffffff81e080c8 0000000000000001
> [ 91.202005] 0000000000000001 ffff88007fb63eb8 ffffffff818b3ffb ffff88007fb6cc00
> [ 91.202005] Call Trace:
> [ 91.202005] <IRQ> d [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 91.202005] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 91.202005] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 91.202005] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 91.202005] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 91.202005] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 91.202005] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 91.202005] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 91.202005] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 91.202005] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 91.202005] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 91.202005] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 91.202005] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 91.202005] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 91.202005] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 91.202005] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 91.202005] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 91.202005] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 91.202005] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 91.202005] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 91.202005] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 91.202005] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 91.202005] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 91.202005] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 91.202005] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 91.202005] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 91.202005] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 91.202005] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 91.202005] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 91.202005] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 91.202005] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 91.202005] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: c2 89 d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 <8b> 03 84 c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3
> [ 91.202005] NMI backtrace for cpu 12
> [ 91.202005] CPU: 12 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007cb27080 ti: ffff88007c674000 task.ti: ffff88007c674000
> [ 91.202005] RIP: 0010:[<ffffffff81339453>] [<ffffffff81339453>] delay_tsc+0x23/0xc0
> [ 91.202005] RSP: 0000:ffff88007c677d00 EFLAGS: 00000002
> [ 91.202005] RAX: 000000000000000c RBX: ffff88007fb6cc00 RCX: 0000000000000002
> [ 91.202005] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 91.202005] RBP: ffff88007c677d20 R08: ffff88007c674000 R09: ffff88007fb6cc00
> [ 91.202005] R10: ffff88007c677e30 R11: 000000000000002d R12: 00000000c7d753c2
> [ 91.202005] R13: 0000000000000001 R14: 000000000000000c R15: ffff88007c677dd0
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] ffff88007fb6cc00 00000000c7d753c2 0000000000000001 00000000cfbb42a0
> [ 91.202005] ffff88007c677d30 ffffffff8133930a ffff88007c677d60 ffffffff810930c7
> [ 91.202005] 0000000000000286 ffff88007fb6cc00 ffff88007fb6cc00 000000000000cc00
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff8133930a>] __delay+0xa/0x10
> [ 91.202005] [<ffffffff810930c7>] do_raw_spin_lock+0x87/0x150
> [ 91.202005] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 91.202005] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 91.202005] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 91.202005] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 91.202005] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: 5d 41 5e 41 5f 5d c3 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd bf 01 00 00 00 e8 68 ec d3 ff e8 73 ec 00 00 41 89 c6 0f ae e8 <0f> 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00
> [ 91.202005] NMI backtrace for cpu 14
> [ 91.202005] CPU: 14 PID: 785 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007cb23200 ti: ffff88007cbb8000 task.ti: ffff88007cbb8000
> [ 91.202005] RIP: 0010:[<ffffffff81078120>] [<ffffffff81078120>] preempt_count_add+0x70/0xc0
> [ 91.202005] RSP: 0018:ffff88007cbbbd98 EFLAGS: 00000246
> [ 91.202005] RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000001
> [ 91.202005] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: 0000000000000001
> [ 91.202005] RBP: ffff88007cbbbda0 R08: ffff88007cbb8000 R09: 0000000000000002
> [ 91.202005] R10: 0000000000000000 R11: 0000000000000001 R12: 000000c2beb198e2
> [ 91.202005] R13: 00000000000aa2cd R14: 000000000000000e R15: ffffffff820d5fe0
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] 000000c2beb32182 ffff88007cbbbdd0 ffffffff8133946d 0000000000000000
> [ 91.202005] ffff88007cbbbe20 00000037e5c0ae24 000000000000046f ffff88007cbbbde0
> [ 91.202005] ffffffff81339337 ffff88007cbbbe00 ffffffff810addf7 0000000000000000
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff8133946d>] delay_tsc+0x3d/0xc0
> [ 91.202005] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 91.202005] [<ffffffff810addf7>] rcu_read_delay+0xa7/0xb0
> [ 91.202005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: 8b 05 a5 07 0a 01 85 c0 75 da 48 c7 c1 f0 57 c9 81 48 c7 c2 1e 0a c9 81 be e1 0b 00 00 48 c7 c7 fb dd c9 81 e8 52 f0 fd ff eb b9 <48> 8b 45 00 48 8b 58 08 48 89 df e8 80 99 01 00 85 c0 75 13 65
> [ 91.202005] NMI backtrace for cpu 15
> [ 91.202005] CPU: 15 PID: 778 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202005] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202005] task: ffff88007c66d780 ti: ffff88007c664000 task.ti: ffff88007c664000
> [ 91.202005] RIP: 0010:[<ffffffff810add72>] [<ffffffff810add72>] rcu_read_delay+0x22/0xb0
> [ 91.202005] RSP: 0018:ffff88007c667df0 EFLAGS: 00000246
> [ 91.202005] RAX: 0000000000000036 RBX: 0000000000000000 RCX: 000000000016e360
> [ 91.202005] RDX: 0000000000103495 RSI: ffff88007fbf27d8 RDI: ffff88007c667e20
> [ 91.202005] RBP: ffff88007c667e00 R08: ffff88007c664000 R09: ffff88007fbf53f0
> [ 91.202005] R10: ffff88007c667e30 R11: 0000000000000001 R12: ffff88007c667e20
> [ 91.202005] R13: 00000037e5c12d14 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 91.202005] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 91.202005] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202005] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202005] Stack:
> [ 91.202005] 0000000000000000 0000000000000000 ffff88007c667ea8 ffffffff810ad458
> [ 91.202005] 0000000000000000 0000000081a0a240 c0b2cf292ad504e4 00000000000018bf
> [ 91.202005] ffff88007c5e3de0 ffff88007fbecf60 00000000fffcd063 ffffffff810ad590
> [ 91.202005] Call Trace:
> [ 91.202005] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202005] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202005] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202005] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202005] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202005] Code: ff ff 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 49 89 fc e8 a1 83 07 00 48 63 0d 0e 95 02 01 31 d2 48 69 c9 a0 86 01 00 48 f7 f1 <48> 85 d2 75 15 bb 32 00 00 00 bf 58 89 41 00 e8 8a b5 28 00 48
> [ 91.202004] BUG: spinlock lockup suspected on CPU#12, rcu_torture_rea/790
> [ 91.202004] lock: 0xffff88007fb6cc00, .magic: dead4ead, .owner: torture_onoff/794, .owner_cpu: 11
> [ 91.202004] CPU: 12 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] ffff88007fb6cc00 ffff88007c677d10 ffffffff8132cd6c ffff88007c67a580
> [ 91.202004] ffff88007c677d30 ffffffff81092fb3 ffff88007fb6cc00 00000000cfbb42a0
> [ 91.202004] ffff88007c677d60 ffffffff810930db 0000000000000286 ffff88007fb6cc00
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff8132cd6c>] dump_stack+0x4e/0x82
> [ 91.202004] [<ffffffff81092fb3>] spin_dump+0x73/0xc0
> [ 91.202004] [<ffffffff810930db>] do_raw_spin_lock+0x9b/0x150
> [ 91.202004] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 91.202004] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 91.202004] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 91.202004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 91.202004] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Sending NMI to all CPUs:
> [ 91.202004] NMI backtrace for cpu 0
> [ 91.202004] CPU: 0 PID: 777 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007c66be80 ti: ffff88007c660000 task.ti: ffff88007c660000
> [ 91.202004] RIP: 0010:[<ffffffff810920af>] [<ffffffff810920af>] queued_spin_lock_slowpath+0x16f/0x1a0
> [ 91.202004] RSP: 0018:ffff88007c663d18 EFLAGS: 00000002
> [ 91.202004] RAX: 0000000000000101 RBX: ffff88007fbacc00 RCX: 0000000000000001
> [ 91.202004] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 91.202004] RBP: ffff88007c663d30 R08: 00000000000006e7 R09: 00000000000006e4
> [ 91.202004] R10: ffff88007c663f58 R11: 00000000000006e4 R12: 00000000cfbb42a0
> [ 91.202004] R13: 0000000000000001 R14: 00000000cfbb42a0 R15: ffff88007c663dd0
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd75020 CR3: 0000000001e0f000 CR4: 00000000000006f0
> [ 91.202004] Stack:
> [ 91.202004] ffff88007fbacc00 00000000cfbb42a0 0000000000000001 ffff88007c663d60
> [ 91.202004] ffffffff81093185 0000000000000286 ffff88007fbacc00 ffff88007fbacc00
> [ 91.202004] 000000000000cc00 ffff88007c663d80 ffffffff818b401f 000000000000000d
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 91.202004] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 91.202004] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 91.202004] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 91.202004] [<ffffffff818af940>] ? preempt_schedule+0x30/0x30
> [ 91.202004] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: c2 89 d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 <8b> 03 84 c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3
> [ 91.202004] NMI backtrace for cpu 2
> [ 91.202004] CPU: 2 PID: 787 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007cb24b00 ti: ffff88007c680000 task.ti: ffff88007c680000
> [ 91.202004] RIP: 0010:[<ffffffff81347fe8>] [<ffffffff81347fe8>] check_preemption_disabled+0x8/0xe0
> [ 91.202004] RSP: 0018:ffff88007c683d90 EFLAGS: 00000246
> [ 91.202004] RAX: 0000000080000001 RBX: 000000c7ab3fe108 RCX: 0000000000000001
> [ 91.202004] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 91.202004] RBP: ffff88007c683da0 R08: ffff88007c680000 R09: 0000000000000002
> [ 91.202004] R10: 0000000000000000 R11: 0000000000000001 R12: 000000c7ab3f6534
> [ 91.202004] R13: 00000000000a9fb8 R14: 0000000000000002 R15: ffffffff820d5fe0
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fa40000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] ffff88007c683da0 ffffffff813480d7 ffff88007c683dd0 ffffffff81339472
> [ 91.202004] 0000000000000000 ffff88007c683e20 00000039515b4c4d 000000000000046f
> [ 91.202004] ffff88007c683de0 ffffffff81339337 ffff88007c683e00 ffffffff810addf7
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff813480d7>] ? debug_smp_processor_id+0x17/0x20
> [ 91.202004] [<ffffffff81339472>] delay_tsc+0x42/0xc0
> [ 91.202004] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 91.202004] [<ffffffff810addf7>] rcu_read_delay+0xa7/0xb0
> [ 91.202004] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: 40 08 00 00 00 00 e9 1b ff ff ff 4d 89 e7 4c 8b 6d c8 49 83 cf 01 e9 0b ff ff ff 0f 1f 84 00 00 00 00 00 55 65 8b 05 a8 2d cc 7e <48> 89 e5 41 56 41 55 41 54 53 65 8b 1d 27 21 cc 7e a9 ff ff ff
> [ 91.202004] NMI backtrace for cpu 6
> [ 91.202004] CPU: 6 PID: 784 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007cb22580 ti: ffff88007c624000 task.ti: ffff88007c624000
> [ 91.202004] RIP: 0010:[<ffffffff810addac>] [<ffffffff810addac>] rcu_read_delay+0x5c/0xb0
> [ 91.202004] RSP: 0018:ffff88007c627df0 EFLAGS: 00000202
> [ 91.202004] RAX: 00000000000a4fd6 RBX: 0000000000000000 RCX: 0000000000001770
> [ 91.202004] RDX: 0000000000000e75 RSI: ffff88007fad27d8 RDI: ffff88007c627e20
> [ 91.202004] RBP: ffff88007c627e00 R08: ffff88007c624000 R09: ffff88007fad53f0
> [ 91.202004] R10: ffff88007c627e30 R11: 000000000000005a R12: ffff88007c627e20
> [ 91.202004] R13: 00000039515b8490 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fac0000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] 0000000000000000 0000000000000000 ffff88007c627ea8 ffffffff810ad458
> [ 91.202004] 0000000000000000 0000000081a0a240 4f1dab463615f1af 0000000000000b21
> [ 91.202004] ffff88007cc53d40 ffff88007c50bdf0 00000000fffcd063 ffffffff810ad590
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: e8 8a b5 28 00 48 83 eb 01 75 f0 4c 89 e7 e8 6c 83 07 00 48 63 15 d9 94 02 01 48 8d 14 92 48 8d 0c 92 31 d2 48 c1 e1 04 48 f7 f1 <48> 85 d2 74 3c 65 8b 05 d8 cf f5 7e a9 ff ff ff 7f 74 05 5b 41
> [ 91.202004] NMI backtrace for cpu 7
> [ 91.202004] CPU: 7 PID: 783 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007cb21900 ti: ffff88007c620000 task.ti: ffff88007c620000
> [ 91.202004] RIP: 0010:[<ffffffff8133947c>] [<ffffffff8133947c>] delay_tsc+0x4c/0xc0
> [ 91.202004] RSP: 0018:ffff88007c623db0 EFLAGS: 00000246
> [ 91.202004] RAX: 00000000ab406ce4 RBX: 000000c7ab406c44 RCX: 0000000000000001
> [ 91.202004] RDX: 00000000000000c7 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 91.202004] RBP: ffff88007c623dd0 R08: ffff88007c620000 R09: 0000000000000002
> [ 91.202004] R10: 0000000000000000 R11: 0000000000000001 R12: 000000c7ab2cda1c
> [ 91.202004] R13: 0000000000351ec1 R14: 0000000000000007 R15: ffffffff820d5fe0
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fae0000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] 0000000000000015 ffff88007c623e20 000000394df2e808 000000000000046f
> [ 91.202004] ffff88007c623de0 ffffffff81339337 ffff88007c623e00 ffffffff810add86
> [ 91.202004] 0000000000000000 0000000000000000 ffff88007c623ea8 ffffffff810ad458
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 91.202004] [<ffffffff810add86>] rcu_read_delay+0x36/0xb0
> [ 91.202004] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: ae e8 0f 31 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 43 ec d3 ff e8 4e ec 00 00 44 39 f0 75 36 0f ae e8 0f 31 <48> c1 e2 20 48 89 d3 48 09 c3 48 89 d8 4c 29 e0 49 39 c5 76 24
> [ 91.202004] NMI backtrace for cpu 9
> [ 91.202004] CPU: 9 PID: 780 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007c66a580 ti: ffff88007c654000 task.ti: ffff88007c654000
> [ 91.202004] RIP: 0010:[<ffffffff810a892f>] [<ffffffff810a892f>] __rcu_read_unlock+0x2f/0x50
> [ 91.202004] RSP: 0018:ffff88007c657de8 EFLAGS: 00000246
> [ 91.202004] RAX: 0000000000000001 RBX: ffff88007c66a580 RCX: 0000000000000001
> [ 91.202004] RDX: 0000000080000001 RSI: ffffffff81d29759 RDI: 0000000000000000
> [ 91.202004] RBP: ffff88007c657df0 R08: ffff88007c654000 R09: ffff88007fb353f0
> [ 91.202004] R10: ffff88007c657e30 R11: 0000000000000078 R12: 0000000000000000
> [ 91.202004] R13: 00000039515bac4a R14: 000000000000046f R15: ffffffff820d5fe0
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fb20000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd5f720 CR3: 000000007b0a0000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] 0000000000000000 ffff88007c657e00 ffffffff810accc9 ffff88007c657ea8
> [ 91.202004] ffffffff810ad3c2 0000000000000000 0000000081a0a240 142e046850c04feb
> [ 91.202004] 0000000000001bad 0000000000000000 ffff88007fb2cf60 00000000fffcd063
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff810accc9>] rcu_torture_read_unlock+0x9/0x10
> [ 91.202004] [<ffffffff810ad3c2>] rcu_torture_reader+0x112/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: 53 65 48 8b 1c 25 00 ae 00 00 8b 83 50 03 00 00 83 f8 01 74 0c 83 e8 01 89 83 50 03 00 00 5b 5d c3 c7 83 50 03 00 00 00 00 00 80 <8b> 83 54 03 00 00 85 c0 75 0d c7 83 50 03 00 00 00 00 00 00 5b
> [ 91.202004] NMI backtrace for cpu 10
> [ 91.202004] CPU: 10 PID: 0 Comm: swapper/10 Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007cc98c80 ti: ffff88007cca4000 task.ti: ffff88007cca4000
> [ 91.202004] RIP: 0010:[<ffffffff81092067>] [<ffffffff81092067>] queued_spin_lock_slowpath+0x127/0x1a0
> [ 91.202004] RSP: 0018:ffff88007fb43d90 EFLAGS: 00000002
> [ 91.202004] RAX: 0000000000000000 RBX: ffff88007fb6cc00 RCX: ffff88007fb55e80
> [ 91.202004] RDX: 00000000002c0101 RSI: ffffffff81ca0d44 RDI: 00000000002c0000
> [ 91.202004] RBP: ffff88007fb43da8 R08: 0000000000000000 R09: 0000000000000583
> [ 91.202004] R10: ffff88007cca7f58 R11: 0000000000000583 R12: 0000000000000000
> [ 91.202004] R13: ffff88007fb55e80 R14: 00000000cfbb42a0 R15: 0000000000000000
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fb40000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] ffff88007fb6cc00 00000000cfbb42a0 0000000000000001 ffff88007fb43dd8
> [ 91.202004] ffffffff81093185 ffff88007fb6cc00 ffffffff820d8c80 ffff88007fb6cc00
> [ 91.202004] 0000000000000000 ffff88007fb43df0 ffffffff818b3fda 000000000000000b
> [ 91.202004] Call Trace:
> [ 91.202004] <IRQ> d [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 91.202004] [<ffffffff818b3fda>] _raw_spin_lock+0x1a/0x20
> [ 91.202004] [<ffffffff810b96b6>] add_timer_on+0x76/0x150
> [ 91.202004] [<ffffffff810c35e7>] clocksource_watchdog+0x217/0x2f0
> [ 91.202004] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 91.202004] [<ffffffff810b8e10>] call_timer_fn+0x30/0x120
> [ 91.202004] [<ffffffff810c33d0>] ? clocksource_unregister+0x50/0x50
> [ 91.202004] [<ffffffff810b937b>] run_timer_softirq+0x20b/0x2b0
> [ 91.202004] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 91.202004] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 91.202004] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 91.202004] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 91.202004] <EOI> d [<ffffffff8100f303>] ? default_idle+0x13/0xd0
> [ 91.202004] [<ffffffff8100fafa>] arch_cpu_idle+0xa/0x10
> [ 91.202004] [<ffffffff8108fd65>] default_idle_call+0x25/0x30
> [ 91.202004] [<ffffffff8108fff7>] cpu_startup_entry+0x287/0x2e0
> [ 91.202004] [<ffffffff8103bf29>] start_secondary+0xf9/0x100
> [ 91.202004] Code: 48 03 14 c5 20 f5 f2 81 48 89 0a 8b 41 08 85 c0 75 09 f3 90 8b 41 08 85 c0 74 f7 4c 8b 01 4d 85 c0 74 08 41 0f 18 08 eb 02 f3 90 <8b> 13 66 85 d2 75 f7 be 01 00 00 00 eb 10 89 d0 f0 0f b1 33 39
> [ 91.202004] NMI backtrace for cpu 11
> [ 91.202004] CPU: 11 PID: 794 Comm: torture_onoff Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007c67a580 ti: ffff88007c63c000 task.ti: ffff88007c63c000
> [ 91.202004] RIP: 0010:[<ffffffff810920b1>] [<ffffffff810920b1>] queued_spin_lock_slowpath+0x171/0x1a0
> [ 91.202004] RSP: 0000:ffff88007fb63e58 EFLAGS: 00000002
> [ 91.202004] RAX: 00000000002c0101 RBX: ffff88007fb6cc00 RCX: 0000000000000001
> [ 91.202004] RDX: 0000000000000101 RSI: 0000000000000001 RDI: 0000000000000101
> [ 91.202004] RBP: ffff88007fb63e70 R08: 00000000000006e7 R09: 0000000000000418
> [ 91.202004] R10: ffff88007c63ff58 R11: 0000000000000418 R12: 00000000cfbb42a0
> [ 91.202004] R13: 0000000000000001 R14: 00000000cfbb42a0 R15: 0000000000000000
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] ffff88007fb6cc00 00000000cfbb42a0 0000000000000001 ffff88007fb63ea0
> [ 91.202004] ffffffff81093185 ffff88007fb6cc00 ffffffff81e080c8 0000000000000001
> [ 91.202004] 0000000000000001 ffff88007fb63eb8 ffffffff818b3ffb ffff88007fb6cc00
> [ 91.202004] Call Trace:
> [ 91.202004] <IRQ> d [<ffffffff81093185>] do_raw_spin_lock+0x145/0x150
> [ 91.202004] [<ffffffff818b3ffb>] _raw_spin_lock_irq+0x1b/0x20
> [ 91.202004] [<ffffffff810b91b0>] run_timer_softirq+0x40/0x2b0
> [ 91.202004] [<ffffffff810c6ddd>] ? clockevents_program_event+0x7d/0x120
> [ 91.202004] [<ffffffff8105b613>] __do_softirq+0xd3/0x280
> [ 91.202004] [<ffffffff8105b8d2>] irq_exit+0x42/0x50
> [ 91.202004] [<ffffffff8103de5d>] smp_apic_timer_interrupt+0x3d/0x50
> [ 91.202004] [<ffffffff818b538f>] apic_timer_interrupt+0x7f/0x90
> [ 91.202004] <EOI> d [<ffffffff818b414f>] ? _raw_spin_unlock_irq+0xf/0x30
> [ 91.202004] [<ffffffff818b4149>] ? _raw_spin_unlock_irq+0x9/0x30
> [ 91.202004] [<ffffffff810d4da6>] acct_collect+0x166/0x1a0
> [ 91.202004] [<ffffffff81058cd9>] do_exit+0x4f9/0xc00
> [ 91.202004] [<ffffffff810087e4>] oops_end+0x84/0xb0
> [ 91.202004] [<ffffffff8104a612>] no_context+0x102/0x330
> [ 91.202004] [<ffffffff8104a8b5>] __bad_area_nosemaphore+0x75/0x1f0
> [ 91.202004] [<ffffffff8104aa3e>] bad_area_nosemaphore+0xe/0x10
> [ 91.202004] [<ffffffff8104ac95>] __do_page_fault+0x85/0x450
> [ 91.202004] [<ffffffff8104b06c>] do_page_fault+0xc/0x10
> [ 91.202004] [<ffffffff818b6422>] page_fault+0x22/0x30
> [ 91.202004] [<ffffffff810b9452>] ? migrate_timer_list+0x32/0xc0
> [ 91.202004] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> [ 91.202004] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> [ 91.202004] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> [ 91.202004] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> [ 91.202004] [<ffffffff81057852>] _cpu_down+0x212/0x350
> [ 91.202004] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> [ 91.202004] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> [ 91.202004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 91.202004] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> [ 91.202004] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> [ 91.202004] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> [ 91.202004] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: d0 66 31 c0 39 c7 74 e7 4d 85 c0 c6 03 01 74 30 41 c7 40 08 01 00 00 00 e9 4e ff ff ff 83 fa 01 75 07 e9 4b ff ff ff f3 90 8b 03 <84> c0 75 f8 b8 01 00 00 00 66 89 03 5b 41 5c 41 5d 5d c3 f3 90
> [ 91.202004] NMI backtrace for cpu 12
> [ 91.202004] CPU: 12 PID: 790 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007cb27080 ti: ffff88007c674000 task.ti: ffff88007c674000
> [ 91.202004] RIP: 0010:[<ffffffff8103ef7d>] [<ffffffff8103ef7d>] default_send_IPI_mask_sequence_phys+0x9d/0xd0
> [ 91.202004] RSP: 0000:ffff88007c677c90 EFLAGS: 00000046
> [ 91.202004] RAX: 0000000000000400 RBX: 000000000000a130 RCX: 000000000000000c
> [ 91.202004] RDX: 000000000000000c RSI: 0000000000000010 RDI: 0000000000000300
> [ 91.202004] RBP: ffff88007c677cc8 R08: 0000000000000000 R09: 000000000000dec4
> [ 91.202004] R10: ffff88007c677f58 R11: 00000000000006fb R12: ffffffff81f31740
> [ 91.202004] R13: 0000000000000400 R14: 0000000000000002 R15: 000000000000000c
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fb80000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] 0000000000000086 0000000c7c677ca0 000000000000ff40 0000000000000001
> [ 91.202004] ffffffff8103fd20 00000000cfbb42a0 ffff88007c677dd0 ffff88007c677cd8
> [ 91.202004] ffffffff8103fd36 ffff88007c677d20 ffffffff81331299 ffffffff81008b50
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff8103fd20>] ? irq_force_complete_move+0x20/0x20
> [ 91.202004] [<ffffffff8103fd36>] nmi_raise_cpu_backtrace+0x16/0x20
> [ 91.202004] [<ffffffff81331299>] nmi_trigger_all_cpu_backtrace+0x259/0x270
> [ 91.202004] [<ffffffff81008b50>] ? show_stack+0x20/0x50
> [ 91.202004] [<ffffffff8103fd74>] arch_trigger_all_cpu_backtrace+0x14/0x20
> [ 91.202004] [<ffffffff810930e5>] do_raw_spin_lock+0xa5/0x150
> [ 91.202004] [<ffffffff818b401f>] _raw_spin_lock_irqsave+0x1f/0x30
> [ 91.202004] [<ffffffff810b8faf>] lock_timer_base.isra.23+0x4f/0x70
> [ 91.202004] [<ffffffff810ba6fa>] mod_timer+0x6a/0x200
> [ 91.202004] [<ffffffff81126479>] ? stutter_wait+0x49/0xc0
> [ 91.202004] [<ffffffff810ad557>] rcu_torture_reader+0x2a7/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: 90 8b 0c 25 00 c3 5f ff 80 e5 10 75 f2 89 d0 c1 e0 18 89 04 25 10 c3 5f ff 41 83 fe 02 44 89 e8 41 0f 45 c6 89 04 25 00 c3 5f ff <eb> 91 48 8b 05 32 09 ef 00 89 55 d4 ff 90 18 01 00 00 8b 55 d4
> [ 91.202004] NMI backtrace for cpu 14
> [ 91.202004] CPU: 14 PID: 785 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007cb23200 ti: ffff88007cbb8000 task.ti: ffff88007cbb8000
> [ 91.202004] RIP: 0010:[<ffffffff81347fef>] [<ffffffff81347fef>] check_preemption_disabled+0xf/0xe0
> [ 91.202004] RSP: 0018:ffff88007cbbbd80 EFLAGS: 00000246
> [ 91.202004] RAX: 0000000080000001 RBX: 000000c7ab4487ce RCX: 0000000000000001
> [ 91.202004] RDX: 0000000000000000 RSI: ffffffff81ca0d44 RDI: ffffffff81cbdfe7
> [ 91.202004] RBP: ffff88007cbbbd90 R08: ffff88007cbb8000 R09: ffff88007fbd53f0
> [ 91.202004] R10: 0000000000000000 R11: 0000000000000001 R12: 000000c7ab40f0d2
> [ 91.202004] R13: 00000000000aa2cd R14: 000000000000000e R15: ffffffff820d5fe0
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fbc0000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] 00000000000aa2cd 000000000000000e ffff88007cbbbda0 ffffffff813480d7
> [ 91.202004] ffff88007cbbbdd0 ffffffff81339472 0000000000000000 ffff88007cbbbe20
> [ 91.202004] 00000039515bbe80 000000000000046f ffff88007cbbbde0 ffffffff81339337
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff813480d7>] debug_smp_processor_id+0x17/0x20
> [ 91.202004] [<ffffffff81339472>] delay_tsc+0x42/0xc0
> [ 91.202004] [<ffffffff81339337>] __const_udelay+0x27/0x30
> [ 91.202004] [<ffffffff810addf7>] rcu_read_delay+0xa7/0xb0
> [ 91.202004] [<ffffffff810ad458>] rcu_torture_reader+0x1a8/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: 1b ff ff ff 4d 89 e7 4c 8b 6d c8 49 83 cf 01 e9 0b ff ff ff 0f 1f 84 00 00 00 00 00 55 65 8b 05 a8 2d cc 7e 48 89 e5 41 56 41 55 <41> 54 53 65 8b 1d 27 21 cc 7e a9 ff ff ff 7f 74 0b 89 d8 5b 41
> [ 91.202004] NMI backtrace for cpu 15
> [ 91.202004] CPU: 15 PID: 778 Comm: rcu_torture_rea Tainted: G D 4.5.0-rc1+ #14
> [ 91.202004] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> [ 91.202004] task: ffff88007c66d780 ti: ffff88007c664000 task.ti: ffff88007c664000
> [ 91.202004] RIP: 0010:[<ffffffff813480f3>] [<ffffffff813480f3>] __this_cpu_preempt_check+0x13/0x20
> [ 91.202004] RSP: 0018:ffff88007c667e00 EFLAGS: 00000202
> [ 91.202004] RAX: 000000000000000f RBX: 0000000000000000 RCX: 00000000000493e0
> [ 91.202004] RDX: 0000000000000000 RSI: ffffffff81d29759 RDI: ffffffff81cbdff8
> [ 91.202004] RBP: ffff88007c667e00 R08: ffff88007c664000 R09: ffff88007fbf53f0
> [ 91.202004] R10: ffff88007c667e30 R11: 0000000000000001 R12: 0000000000000000
> [ 91.202004] R13: 00000039515cdbe8 R14: 000000000000046f R15: ffffffff820d5fe0
> [ 91.202004] FS: 0000000000000000(0000) GS:ffff88007fbe0000(0000) knlGS:0000000000000000
> [ 91.202004] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 91.202004] CR2: 000055f32cd5f720 CR3: 0000000001e0f000 CR4: 00000000000006e0
> [ 91.202004] Stack:
> [ 91.202004] ffff88007c667ea8 ffffffff810ad385 0000000000000000 0000000081a0a240
> [ 91.202004] 8690c2c9a6c7a479 0000000000001532 ffff88007c5e3de0 ffff88007fbecf60
> [ 91.202004] 00000000fffcd063 ffffffff810ad590 0000000000000000 ffffffff0000000f
> [ 91.202004] Call Trace:
> [ 91.202004] [<ffffffff810ad385>] rcu_torture_reader+0xd5/0x2e0
> [ 91.202004] [<ffffffff810ad590>] ? rcu_torture_reader+0x2e0/0x2e0
> [ 91.202004] [<ffffffff810ad2b0>] ? rcutorture_trace_dump.part.7+0x20/0x20
> [ 91.202004] [<ffffffff810732f6>] kthread+0xd6/0xf0
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> [ 91.202004] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> [ 91.202004] Code: 48 c7 c7 e7 df cb 81 48 89 e5 e8 09 ff ff ff 5d c3 0f 1f 80 00 00 00 00 55 48 89 fe 48 c7 c7 f8 df cb 81 48 89 e5 e8 ed fe ff ff <5d> c3 66 2e 0f 1f 84 00 00 00 00 00 90 55 48 85 d2 48 89 e5 41

> #
> # Automatically generated file; DO NOT EDIT.
> # Linux/x86 4.5.0-rc1 Kernel Configuration
> #
> CONFIG_64BIT=y
> CONFIG_X86_64=y
> CONFIG_X86=y
> CONFIG_INSTRUCTION_DECODER=y
> CONFIG_PERF_EVENTS_INTEL_UNCORE=y
> CONFIG_OUTPUT_FORMAT="elf64-x86-64"
> CONFIG_ARCH_DEFCONFIG="arch/x86/configs/x86_64_defconfig"
> CONFIG_LOCKDEP_SUPPORT=y
> CONFIG_STACKTRACE_SUPPORT=y
> CONFIG_MMU=y
> CONFIG_ARCH_MMAP_RND_BITS_MIN=28
> CONFIG_ARCH_MMAP_RND_BITS_MAX=32
> CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MIN=8
> CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX=16
> CONFIG_NEED_DMA_MAP_STATE=y
> CONFIG_NEED_SG_DMA_LENGTH=y
> CONFIG_GENERIC_ISA_DMA=y
> CONFIG_GENERIC_BUG=y
> CONFIG_GENERIC_BUG_RELATIVE_POINTERS=y
> CONFIG_GENERIC_HWEIGHT=y
> CONFIG_ARCH_MAY_HAVE_PC_FDC=y
> CONFIG_RWSEM_XCHGADD_ALGORITHM=y
> CONFIG_GENERIC_CALIBRATE_DELAY=y
> CONFIG_ARCH_HAS_CPU_RELAX=y
> CONFIG_ARCH_HAS_CACHE_LINE_SIZE=y
> CONFIG_HAVE_SETUP_PER_CPU_AREA=y
> CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK=y
> CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK=y
> CONFIG_ARCH_HIBERNATION_POSSIBLE=y
> CONFIG_ARCH_SUSPEND_POSSIBLE=y
> CONFIG_ARCH_WANT_HUGE_PMD_SHARE=y
> CONFIG_ARCH_WANT_GENERAL_HUGETLB=y
> CONFIG_ZONE_DMA32=y
> CONFIG_AUDIT_ARCH=y
> CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING=y
> CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC=y
> CONFIG_HAVE_INTEL_TXT=y
> CONFIG_X86_64_SMP=y
> CONFIG_ARCH_HWEIGHT_CFLAGS="-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11"
> CONFIG_ARCH_SUPPORTS_UPROBES=y
> CONFIG_FIX_EARLYCON_MEM=y
> CONFIG_PGTABLE_LEVELS=4
> CONFIG_DEFCONFIG_LIST="/lib/modules/$UNAME_RELEASE/.config"
> CONFIG_IRQ_WORK=y
> CONFIG_BUILDTIME_EXTABLE_SORT=y
>
> #
> # General setup
> #
> CONFIG_INIT_ENV_ARG_LIMIT=32
> CONFIG_CROSS_COMPILE=""
> # CONFIG_COMPILE_TEST is not set
> CONFIG_LOCALVERSION=""
> # CONFIG_LOCALVERSION_AUTO is not set
> CONFIG_HAVE_KERNEL_GZIP=y
> CONFIG_HAVE_KERNEL_BZIP2=y
> CONFIG_HAVE_KERNEL_LZMA=y
> CONFIG_HAVE_KERNEL_XZ=y
> CONFIG_HAVE_KERNEL_LZO=y
> CONFIG_HAVE_KERNEL_LZ4=y
> CONFIG_KERNEL_GZIP=y
> # CONFIG_KERNEL_BZIP2 is not set
> # CONFIG_KERNEL_LZMA is not set
> # CONFIG_KERNEL_XZ is not set
> # CONFIG_KERNEL_LZO is not set
> # CONFIG_KERNEL_LZ4 is not set
> CONFIG_DEFAULT_HOSTNAME="(none)"
> CONFIG_SWAP=y
> CONFIG_SYSVIPC=y
> CONFIG_SYSVIPC_SYSCTL=y
> CONFIG_POSIX_MQUEUE=y
> CONFIG_POSIX_MQUEUE_SYSCTL=y
> CONFIG_CROSS_MEMORY_ATTACH=y
> CONFIG_FHANDLE=y
> CONFIG_USELIB=y
> CONFIG_AUDIT=y
> CONFIG_HAVE_ARCH_AUDITSYSCALL=y
> CONFIG_AUDITSYSCALL=y
> CONFIG_AUDIT_WATCH=y
> CONFIG_AUDIT_TREE=y
>
> #
> # IRQ subsystem
> #
> CONFIG_GENERIC_IRQ_PROBE=y
> CONFIG_GENERIC_IRQ_SHOW=y
> CONFIG_GENERIC_PENDING_IRQ=y
> CONFIG_IRQ_DOMAIN=y
> CONFIG_IRQ_DOMAIN_HIERARCHY=y
> CONFIG_GENERIC_MSI_IRQ=y
> CONFIG_GENERIC_MSI_IRQ_DOMAIN=y
> # CONFIG_IRQ_DOMAIN_DEBUG is not set
> CONFIG_IRQ_FORCED_THREADING=y
> CONFIG_SPARSE_IRQ=y
> CONFIG_CLOCKSOURCE_WATCHDOG=y
> CONFIG_ARCH_CLOCKSOURCE_DATA=y
> CONFIG_CLOCKSOURCE_VALIDATE_LAST_CYCLE=y
> CONFIG_GENERIC_TIME_VSYSCALL=y
> CONFIG_GENERIC_CLOCKEVENTS=y
> CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y
> CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST=y
> CONFIG_GENERIC_CMOS_UPDATE=y
>
> #
> # Timers subsystem
> #
> CONFIG_TICK_ONESHOT=y
> CONFIG_HZ_PERIODIC=y
> # CONFIG_NO_HZ_IDLE is not set
> # CONFIG_NO_HZ_FULL is not set
> CONFIG_NO_HZ=y
> CONFIG_HIGH_RES_TIMERS=y
>
> #
> # CPU/Task time and stats accounting
> #
> CONFIG_TICK_CPU_ACCOUNTING=y
> # CONFIG_VIRT_CPU_ACCOUNTING_GEN is not set
> # CONFIG_IRQ_TIME_ACCOUNTING is not set
> CONFIG_BSD_PROCESS_ACCT=y
> # CONFIG_BSD_PROCESS_ACCT_V3 is not set
> CONFIG_TASKSTATS=y
> CONFIG_TASK_DELAY_ACCT=y
> CONFIG_TASK_XACCT=y
> CONFIG_TASK_IO_ACCOUNTING=y
>
> #
> # RCU Subsystem
> #
> CONFIG_PREEMPT_RCU=y
> CONFIG_RCU_EXPERT=y
> CONFIG_SRCU=y
> CONFIG_TASKS_RCU=y
> CONFIG_RCU_STALL_COMMON=y
> CONFIG_RCU_FANOUT=2
> CONFIG_RCU_FANOUT_LEAF=2
> CONFIG_TREE_RCU_TRACE=y
> CONFIG_RCU_BOOST=y
> CONFIG_RCU_KTHREAD_PRIO=2
> CONFIG_RCU_BOOST_DELAY=500
> # CONFIG_RCU_NOCB_CPU is not set
> # CONFIG_RCU_EXPEDITE_BOOT is not set
> # CONFIG_BUILD_BIN2C is not set
> # CONFIG_IKCONFIG is not set
> CONFIG_LOG_BUF_SHIFT=18
> CONFIG_LOG_CPU_MAX_BUF_SHIFT=12
> CONFIG_HAVE_UNSTABLE_SCHED_CLOCK=y
> CONFIG_ARCH_SUPPORTS_NUMA_BALANCING=y
> CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH=y
> CONFIG_ARCH_SUPPORTS_INT128=y
> # CONFIG_NUMA_BALANCING is not set
> CONFIG_CGROUPS=y
> # CONFIG_MEMCG is not set
> # CONFIG_BLK_CGROUP is not set
> CONFIG_CGROUP_SCHED=y
> CONFIG_FAIR_GROUP_SCHED=y
> # CONFIG_CFS_BANDWIDTH is not set
> # CONFIG_RT_GROUP_SCHED is not set
> # CONFIG_CGROUP_PIDS is not set
> CONFIG_CGROUP_FREEZER=y
> # CONFIG_CGROUP_HUGETLB is not set
> CONFIG_CPUSETS=y
> CONFIG_PROC_PID_CPUSET=y
> # CONFIG_CGROUP_DEVICE is not set
> CONFIG_CGROUP_CPUACCT=y
> # CONFIG_CGROUP_PERF is not set
> # CONFIG_CGROUP_DEBUG is not set
> # CONFIG_CHECKPOINT_RESTORE is not set
> CONFIG_NAMESPACES=y
> CONFIG_UTS_NS=y
> CONFIG_IPC_NS=y
> # CONFIG_USER_NS is not set
> CONFIG_PID_NS=y
> CONFIG_NET_NS=y
> # CONFIG_SCHED_AUTOGROUP is not set
> # CONFIG_SYSFS_DEPRECATED is not set
> CONFIG_RELAY=y
> CONFIG_BLK_DEV_INITRD=y
> CONFIG_INITRAMFS_SOURCE=""
> CONFIG_RD_GZIP=y
> CONFIG_RD_BZIP2=y
> CONFIG_RD_LZMA=y
> CONFIG_RD_XZ=y
> CONFIG_RD_LZO=y
> CONFIG_RD_LZ4=y
> # CONFIG_CC_OPTIMIZE_FOR_SIZE is not set
> CONFIG_SYSCTL=y
> CONFIG_ANON_INODES=y
> CONFIG_HAVE_UID16=y
> CONFIG_SYSCTL_EXCEPTION_TRACE=y
> CONFIG_HAVE_PCSPKR_PLATFORM=y
> CONFIG_BPF=y
> # CONFIG_EXPERT is not set
> CONFIG_UID16=y
> CONFIG_MULTIUSER=y
> CONFIG_SGETMASK_SYSCALL=y
> CONFIG_SYSFS_SYSCALL=y
> # CONFIG_SYSCTL_SYSCALL is not set
> CONFIG_KALLSYMS=y
> CONFIG_KALLSYMS_ALL=y
> CONFIG_PRINTK=y
> CONFIG_BUG=y
> CONFIG_ELF_CORE=y
> CONFIG_PCSPKR_PLATFORM=y
> CONFIG_BASE_FULL=y
> CONFIG_FUTEX=y
> CONFIG_EPOLL=y
> CONFIG_SIGNALFD=y
> CONFIG_TIMERFD=y
> CONFIG_EVENTFD=y
> # CONFIG_BPF_SYSCALL is not set
> CONFIG_SHMEM=y
> CONFIG_AIO=y
> CONFIG_ADVISE_SYSCALLS=y
> # CONFIG_USERFAULTFD is not set
> CONFIG_PCI_QUIRKS=y
> CONFIG_MEMBARRIER=y
> # CONFIG_EMBEDDED is not set
> CONFIG_HAVE_PERF_EVENTS=y
>
> #
> # Kernel Performance Events And Counters
> #
> CONFIG_PERF_EVENTS=y
> # CONFIG_DEBUG_PERF_USE_VMALLOC is not set
> CONFIG_VM_EVENT_COUNTERS=y
> CONFIG_SLUB_DEBUG=y
> # CONFIG_COMPAT_BRK is not set
> # CONFIG_SLAB is not set
> CONFIG_SLUB=y
> CONFIG_SLUB_CPU_PARTIAL=y
> # CONFIG_SYSTEM_DATA_VERIFICATION is not set
> CONFIG_PROFILING=y
> CONFIG_TRACEPOINTS=y
> CONFIG_KEXEC_CORE=y
> # CONFIG_OPROFILE is not set
> CONFIG_HAVE_OPROFILE=y
> CONFIG_OPROFILE_NMI_TIMER=y
> CONFIG_KPROBES=y
> CONFIG_JUMP_LABEL=y
> # CONFIG_STATIC_KEYS_SELFTEST is not set
> # CONFIG_UPROBES is not set
> # CONFIG_HAVE_64BIT_ALIGNED_ACCESS is not set
> CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS=y
> CONFIG_ARCH_USE_BUILTIN_BSWAP=y
> CONFIG_KRETPROBES=y
> CONFIG_HAVE_IOREMAP_PROT=y
> CONFIG_HAVE_KPROBES=y
> CONFIG_HAVE_KRETPROBES=y
> CONFIG_HAVE_OPTPROBES=y
> CONFIG_HAVE_KPROBES_ON_FTRACE=y
> CONFIG_HAVE_ARCH_TRACEHOOK=y
> CONFIG_HAVE_DMA_CONTIGUOUS=y
> CONFIG_GENERIC_SMP_IDLE_THREAD=y
> CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT=y
> CONFIG_HAVE_REGS_AND_STACK_ACCESS_API=y
> CONFIG_HAVE_DMA_API_DEBUG=y
> CONFIG_HAVE_HW_BREAKPOINT=y
> CONFIG_HAVE_MIXED_BREAKPOINTS_REGS=y
> CONFIG_HAVE_USER_RETURN_NOTIFIER=y
> CONFIG_HAVE_PERF_EVENTS_NMI=y
> CONFIG_HAVE_PERF_REGS=y
> CONFIG_HAVE_PERF_USER_STACK_DUMP=y
> CONFIG_HAVE_ARCH_JUMP_LABEL=y
> CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG=y
> CONFIG_HAVE_ALIGNED_STRUCT_PAGE=y
> CONFIG_HAVE_CMPXCHG_LOCAL=y
> CONFIG_HAVE_CMPXCHG_DOUBLE=y
> CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION=y
> CONFIG_ARCH_WANT_OLD_COMPAT_IPC=y
> CONFIG_HAVE_ARCH_SECCOMP_FILTER=y
> CONFIG_SECCOMP_FILTER=y
> CONFIG_HAVE_CC_STACKPROTECTOR=y
> # CONFIG_CC_STACKPROTECTOR is not set
> CONFIG_CC_STACKPROTECTOR_NONE=y
> # CONFIG_CC_STACKPROTECTOR_REGULAR is not set
> # CONFIG_CC_STACKPROTECTOR_STRONG is not set
> CONFIG_HAVE_CONTEXT_TRACKING=y
> CONFIG_HAVE_VIRT_CPU_ACCOUNTING_GEN=y
> CONFIG_HAVE_IRQ_TIME_ACCOUNTING=y
> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE=y
> CONFIG_HAVE_ARCH_HUGE_VMAP=y
> CONFIG_HAVE_ARCH_SOFT_DIRTY=y
> CONFIG_MODULES_USE_ELF_RELA=y
> CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK=y
> CONFIG_ARCH_HAS_ELF_RANDOMIZE=y
> CONFIG_HAVE_ARCH_MMAP_RND_BITS=y
> CONFIG_ARCH_MMAP_RND_BITS=28
> CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS=y
> CONFIG_ARCH_MMAP_RND_COMPAT_BITS=8
> CONFIG_HAVE_COPY_THREAD_TLS=y
> CONFIG_OLD_SIGSUSPEND3=y
> CONFIG_COMPAT_OLD_SIGACTION=y
>
> #
> # GCOV-based kernel profiling
> #
> # CONFIG_GCOV_KERNEL is not set
> CONFIG_ARCH_HAS_GCOV_PROFILE_ALL=y
> # CONFIG_HAVE_GENERIC_DMA_COHERENT is not set
> CONFIG_SLABINFO=y
> CONFIG_RT_MUTEXES=y
> CONFIG_BASE_SMALL=0
> CONFIG_MODULES=y
> # CONFIG_MODULE_FORCE_LOAD is not set
> CONFIG_MODULE_UNLOAD=y
> CONFIG_MODULE_FORCE_UNLOAD=y
> # CONFIG_MODVERSIONS is not set
> # CONFIG_MODULE_SRCVERSION_ALL is not set
> # CONFIG_MODULE_SIG is not set
> # CONFIG_MODULE_COMPRESS is not set
> CONFIG_MODULES_TREE_LOOKUP=y
> CONFIG_BLOCK=y
> CONFIG_BLK_DEV_BSG=y
> # CONFIG_BLK_DEV_BSGLIB is not set
> # CONFIG_BLK_DEV_INTEGRITY is not set
> # CONFIG_BLK_CMDLINE_PARSER is not set
>
> #
> # Partition Types
> #
> CONFIG_PARTITION_ADVANCED=y
> # CONFIG_ACORN_PARTITION is not set
> # CONFIG_AIX_PARTITION is not set
> CONFIG_OSF_PARTITION=y
> CONFIG_AMIGA_PARTITION=y
> # CONFIG_ATARI_PARTITION is not set
> CONFIG_MAC_PARTITION=y
> CONFIG_MSDOS_PARTITION=y
> CONFIG_BSD_DISKLABEL=y
> CONFIG_MINIX_SUBPARTITION=y
> CONFIG_SOLARIS_X86_PARTITION=y
> CONFIG_UNIXWARE_DISKLABEL=y
> # CONFIG_LDM_PARTITION is not set
> CONFIG_SGI_PARTITION=y
> # CONFIG_ULTRIX_PARTITION is not set
> CONFIG_SUN_PARTITION=y
> CONFIG_KARMA_PARTITION=y
> CONFIG_EFI_PARTITION=y
> # CONFIG_SYSV68_PARTITION is not set
> # CONFIG_CMDLINE_PARTITION is not set
> CONFIG_BLOCK_COMPAT=y
>
> #
> # IO Schedulers
> #
> CONFIG_IOSCHED_NOOP=y
> CONFIG_IOSCHED_DEADLINE=y
> CONFIG_IOSCHED_CFQ=y
> # CONFIG_DEFAULT_DEADLINE is not set
> CONFIG_DEFAULT_CFQ=y
> # CONFIG_DEFAULT_NOOP is not set
> CONFIG_DEFAULT_IOSCHED="cfq"
> CONFIG_UNINLINE_SPIN_UNLOCK=y
> CONFIG_ARCH_SUPPORTS_ATOMIC_RMW=y
> CONFIG_RWSEM_SPIN_ON_OWNER=y
> CONFIG_LOCK_SPIN_ON_OWNER=y
> CONFIG_ARCH_USE_QUEUED_SPINLOCKS=y
> CONFIG_QUEUED_SPINLOCKS=y
> CONFIG_ARCH_USE_QUEUED_RWLOCKS=y
> CONFIG_QUEUED_RWLOCKS=y
> CONFIG_FREEZER=y
>
> #
> # Processor type and features
> #
> CONFIG_ZONE_DMA=y
> CONFIG_SMP=y
> CONFIG_X86_FEATURE_NAMES=y
> CONFIG_X86_FAST_FEATURE_TESTS=y
> CONFIG_X86_MPPARSE=y
> CONFIG_X86_EXTENDED_PLATFORM=y
> # CONFIG_X86_VSMP is not set
> # CONFIG_X86_GOLDFISH is not set
> # CONFIG_X86_INTEL_LPSS is not set
> # CONFIG_X86_AMD_PLATFORM_DEVICE is not set
> # CONFIG_IOSF_MBI is not set
> CONFIG_X86_SUPPORTS_MEMORY_FAILURE=y
> CONFIG_SCHED_OMIT_FRAME_POINTER=y
> # CONFIG_HYPERVISOR_GUEST is not set
> CONFIG_NO_BOOTMEM=y
> # CONFIG_MK8 is not set
> # CONFIG_MPSC is not set
> # CONFIG_MCORE2 is not set
> # CONFIG_MATOM is not set
> CONFIG_GENERIC_CPU=y
> CONFIG_X86_INTERNODE_CACHE_SHIFT=6
> CONFIG_X86_L1_CACHE_SHIFT=6
> CONFIG_X86_TSC=y
> CONFIG_X86_CMPXCHG64=y
> CONFIG_X86_CMOV=y
> CONFIG_X86_MINIMUM_CPU_FAMILY=64
> CONFIG_X86_DEBUGCTLMSR=y
> CONFIG_CPU_SUP_INTEL=y
> CONFIG_CPU_SUP_AMD=y
> CONFIG_CPU_SUP_CENTAUR=y
> CONFIG_HPET_TIMER=y
> CONFIG_HPET_EMULATE_RTC=y
> CONFIG_DMI=y
> # CONFIG_GART_IOMMU is not set
> CONFIG_CALGARY_IOMMU=y
> CONFIG_CALGARY_IOMMU_ENABLED_BY_DEFAULT=y
> CONFIG_SWIOTLB=y
> CONFIG_IOMMU_HELPER=y
> # CONFIG_MAXSMP is not set
> CONFIG_NR_CPUS=16
> CONFIG_SCHED_SMT=y
> CONFIG_SCHED_MC=y
> # CONFIG_PREEMPT_NONE is not set
> # CONFIG_PREEMPT_VOLUNTARY is not set
> CONFIG_PREEMPT=y
> CONFIG_PREEMPT_COUNT=y
> CONFIG_X86_LOCAL_APIC=y
> CONFIG_X86_IO_APIC=y
> CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS=y
> CONFIG_X86_MCE=y
> CONFIG_X86_MCE_INTEL=y
> CONFIG_X86_MCE_AMD=y
> CONFIG_X86_MCE_THRESHOLD=y
> # CONFIG_X86_MCE_INJECT is not set
> CONFIG_X86_THERMAL_VECTOR=y
> # CONFIG_VM86 is not set
> CONFIG_X86_16BIT=y
> CONFIG_X86_ESPFIX64=y
> CONFIG_X86_VSYSCALL_EMULATION=y
> # CONFIG_I8K is not set
> CONFIG_MICROCODE=y
> CONFIG_MICROCODE_INTEL=y
> CONFIG_MICROCODE_AMD=y
> CONFIG_MICROCODE_OLD_INTERFACE=y
> CONFIG_X86_MSR=y
> CONFIG_X86_CPUID=y
> CONFIG_ARCH_PHYS_ADDR_T_64BIT=y
> CONFIG_ARCH_DMA_ADDR_T_64BIT=y
> CONFIG_X86_DIRECT_GBPAGES=y
> CONFIG_NUMA=y
> CONFIG_AMD_NUMA=y
> CONFIG_X86_64_ACPI_NUMA=y
> CONFIG_NODES_SPAN_OTHER_NODES=y
> # CONFIG_NUMA_EMU is not set
> CONFIG_NODES_SHIFT=6
> CONFIG_ARCH_SPARSEMEM_ENABLE=y
> CONFIG_ARCH_SPARSEMEM_DEFAULT=y
> CONFIG_ARCH_SELECT_MEMORY_MODEL=y
> CONFIG_ARCH_PROC_KCORE_TEXT=y
> CONFIG_ILLEGAL_POINTER_VALUE=0xdead000000000000
> CONFIG_SELECT_MEMORY_MODEL=y
> CONFIG_SPARSEMEM_MANUAL=y
> CONFIG_SPARSEMEM=y
> CONFIG_NEED_MULTIPLE_NODES=y
> CONFIG_HAVE_MEMORY_PRESENT=y
> CONFIG_SPARSEMEM_EXTREME=y
> CONFIG_SPARSEMEM_VMEMMAP_ENABLE=y
> CONFIG_SPARSEMEM_ALLOC_MEM_MAP_TOGETHER=y
> CONFIG_SPARSEMEM_VMEMMAP=y
> CONFIG_HAVE_MEMBLOCK=y
> CONFIG_HAVE_MEMBLOCK_NODE_MAP=y
> CONFIG_ARCH_DISCARD_MEMBLOCK=y
> # CONFIG_MOVABLE_NODE is not set
> # CONFIG_HAVE_BOOTMEM_INFO_NODE is not set
> # CONFIG_MEMORY_HOTPLUG is not set
> CONFIG_SPLIT_PTLOCK_CPUS=4
> CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK=y
> CONFIG_COMPACTION=y
> CONFIG_MIGRATION=y
> CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION=y
> CONFIG_PHYS_ADDR_T_64BIT=y
> CONFIG_ZONE_DMA_FLAG=1
> CONFIG_BOUNCE=y
> CONFIG_VIRT_TO_BUS=y
> # CONFIG_KSM is not set
> CONFIG_DEFAULT_MMAP_MIN_ADDR=4096
> CONFIG_ARCH_SUPPORTS_MEMORY_FAILURE=y
> # CONFIG_MEMORY_FAILURE is not set
> # CONFIG_TRANSPARENT_HUGEPAGE is not set
> # CONFIG_CLEANCACHE is not set
> # CONFIG_FRONTSWAP is not set
> # CONFIG_CMA is not set
> # CONFIG_ZPOOL is not set
> # CONFIG_ZBUD is not set
> # CONFIG_ZSMALLOC is not set
> CONFIG_GENERIC_EARLY_IOREMAP=y
> CONFIG_ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT=y
> # CONFIG_IDLE_PAGE_TRACKING is not set
> # CONFIG_X86_PMEM_LEGACY is not set
> CONFIG_X86_CHECK_BIOS_CORRUPTION=y
> CONFIG_X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK=y
> CONFIG_X86_RESERVE_LOW=64
> CONFIG_MTRR=y
> # CONFIG_MTRR_SANITIZER is not set
> CONFIG_X86_PAT=y
> CONFIG_ARCH_USES_PG_UNCACHED=y
> CONFIG_ARCH_RANDOM=y
> CONFIG_X86_SMAP=y
> # CONFIG_X86_INTEL_MPX is not set
> CONFIG_EFI=y
> # CONFIG_EFI_STUB is not set
> CONFIG_SECCOMP=y
> # CONFIG_HZ_100 is not set
> # CONFIG_HZ_250 is not set
> # CONFIG_HZ_300 is not set
> CONFIG_HZ_1000=y
> CONFIG_HZ=1000
> CONFIG_SCHED_HRTICK=y
> CONFIG_KEXEC=y
> # CONFIG_KEXEC_FILE is not set
> CONFIG_CRASH_DUMP=y
> # CONFIG_KEXEC_JUMP is not set
> CONFIG_PHYSICAL_START=0x1000000
> CONFIG_RELOCATABLE=y
> # CONFIG_RANDOMIZE_BASE is not set
> CONFIG_PHYSICAL_ALIGN=0x200000
> CONFIG_HOTPLUG_CPU=y
> # CONFIG_BOOTPARAM_HOTPLUG_CPU0 is not set
> # CONFIG_DEBUG_HOTPLUG_CPU0 is not set
> # CONFIG_COMPAT_VDSO is not set
> # CONFIG_LEGACY_VSYSCALL_NATIVE is not set
> CONFIG_LEGACY_VSYSCALL_EMULATE=y
> # CONFIG_LEGACY_VSYSCALL_NONE is not set
> # CONFIG_CMDLINE_BOOL is not set
> CONFIG_MODIFY_LDT_SYSCALL=y
> CONFIG_HAVE_LIVEPATCH=y
> CONFIG_ARCH_ENABLE_MEMORY_HOTPLUG=y
> CONFIG_USE_PERCPU_NUMA_NODE_ID=y
>
> #
> # Power management and ACPI options
> #
> CONFIG_ARCH_HIBERNATION_HEADER=y
> CONFIG_SUSPEND=y
> CONFIG_SUSPEND_FREEZER=y
> CONFIG_HIBERNATE_CALLBACKS=y
> CONFIG_HIBERNATION=y
> CONFIG_PM_STD_PARTITION=""
> CONFIG_PM_SLEEP=y
> CONFIG_PM_SLEEP_SMP=y
> # CONFIG_PM_AUTOSLEEP is not set
> # CONFIG_PM_WAKELOCKS is not set
> CONFIG_PM=y
> CONFIG_PM_DEBUG=y
> # CONFIG_PM_ADVANCED_DEBUG is not set
> # CONFIG_PM_TEST_SUSPEND is not set
> CONFIG_PM_SLEEP_DEBUG=y
> CONFIG_PM_TRACE=y
> CONFIG_PM_TRACE_RTC=y
> # CONFIG_WQ_POWER_EFFICIENT_DEFAULT is not set
> CONFIG_ACPI=y
> CONFIG_ACPI_LEGACY_TABLES_LOOKUP=y
> CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC=y
> CONFIG_ACPI_SYSTEM_POWER_STATES_SUPPORT=y
> # CONFIG_ACPI_DEBUGGER is not set
> CONFIG_ACPI_SLEEP=y
> # CONFIG_ACPI_PROCFS_POWER is not set
> CONFIG_ACPI_REV_OVERRIDE_POSSIBLE=y
> # CONFIG_ACPI_EC_DEBUGFS is not set
> CONFIG_ACPI_AC=y
> CONFIG_ACPI_BATTERY=y
> CONFIG_ACPI_BUTTON=y
> CONFIG_ACPI_VIDEO=y
> CONFIG_ACPI_FAN=y
> CONFIG_ACPI_DOCK=y
> CONFIG_ACPI_CPU_FREQ_PSS=y
> CONFIG_ACPI_PROCESSOR_IDLE=y
> CONFIG_ACPI_PROCESSOR=y
> CONFIG_ACPI_HOTPLUG_CPU=y
> # CONFIG_ACPI_PROCESSOR_AGGREGATOR is not set
> CONFIG_ACPI_THERMAL=y
> CONFIG_ACPI_NUMA=y
> # CONFIG_ACPI_CUSTOM_DSDT is not set
> # CONFIG_ACPI_INITRD_TABLE_OVERRIDE is not set
> # CONFIG_ACPI_DEBUG is not set
> # CONFIG_ACPI_PCI_SLOT is not set
> CONFIG_X86_PM_TIMER=y
> CONFIG_ACPI_CONTAINER=y
> CONFIG_ACPI_HOTPLUG_IOAPIC=y
> # CONFIG_ACPI_SBS is not set
> # CONFIG_ACPI_HED is not set
> # CONFIG_ACPI_CUSTOM_METHOD is not set
> # CONFIG_ACPI_BGRT is not set
> # CONFIG_ACPI_REDUCED_HARDWARE_ONLY is not set
> # CONFIG_ACPI_NFIT is not set
> CONFIG_HAVE_ACPI_APEI=y
> CONFIG_HAVE_ACPI_APEI_NMI=y
> # CONFIG_ACPI_APEI is not set
> # CONFIG_ACPI_EXTLOG is not set
> # CONFIG_PMIC_OPREGION is not set
> # CONFIG_SFI is not set
>
> #
> # CPU Frequency scaling
> #
> CONFIG_CPU_FREQ=y
> CONFIG_CPU_FREQ_GOV_COMMON=y
> # CONFIG_CPU_FREQ_STAT is not set
> # CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE is not set
> # CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
> CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE=y
> # CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
> # CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
> CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
> # CONFIG_CPU_FREQ_GOV_POWERSAVE is not set
> CONFIG_CPU_FREQ_GOV_USERSPACE=y
> CONFIG_CPU_FREQ_GOV_ONDEMAND=y
> # CONFIG_CPU_FREQ_GOV_CONSERVATIVE is not set
>
> #
> # CPU frequency scaling drivers
> #
> # CONFIG_X86_INTEL_PSTATE is not set
> # CONFIG_X86_PCC_CPUFREQ is not set
> CONFIG_X86_ACPI_CPUFREQ=y
> CONFIG_X86_ACPI_CPUFREQ_CPB=y
> # CONFIG_X86_POWERNOW_K8 is not set
> # CONFIG_X86_AMD_FREQ_SENSITIVITY is not set
> # CONFIG_X86_SPEEDSTEP_CENTRINO is not set
> # CONFIG_X86_P4_CLOCKMOD is not set
>
> #
> # shared options
> #
> # CONFIG_X86_SPEEDSTEP_LIB is not set
>
> #
> # CPU Idle
> #
> CONFIG_CPU_IDLE=y
> # CONFIG_CPU_IDLE_GOV_LADDER is not set
> CONFIG_CPU_IDLE_GOV_MENU=y
> # CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED is not set
> # CONFIG_INTEL_IDLE is not set
>
> #
> # Memory power savings
> #
> # CONFIG_I7300_IDLE is not set
>
> #
> # Bus options (PCI etc.)
> #
> CONFIG_PCI=y
> CONFIG_PCI_DIRECT=y
> CONFIG_PCI_MMCONFIG=y
> CONFIG_PCI_DOMAINS=y
> CONFIG_PCIEPORTBUS=y
> # CONFIG_HOTPLUG_PCI_PCIE is not set
> CONFIG_PCIEAER=y
> # CONFIG_PCIE_ECRC is not set
> # CONFIG_PCIEAER_INJECT is not set
> CONFIG_PCIEASPM=y
> # CONFIG_PCIEASPM_DEBUG is not set
> CONFIG_PCIEASPM_DEFAULT=y
> # CONFIG_PCIEASPM_POWERSAVE is not set
> # CONFIG_PCIEASPM_PERFORMANCE is not set
> CONFIG_PCIE_PME=y
> CONFIG_PCI_BUS_ADDR_T_64BIT=y
> CONFIG_PCI_MSI=y
> CONFIG_PCI_MSI_IRQ_DOMAIN=y
> # CONFIG_PCI_DEBUG is not set
> # CONFIG_PCI_REALLOC_ENABLE_AUTO is not set
> # CONFIG_PCI_STUB is not set
> CONFIG_HT_IRQ=y
> CONFIG_PCI_ATS=y
> # CONFIG_PCI_IOV is not set
> CONFIG_PCI_PRI=y
> CONFIG_PCI_PASID=y
> CONFIG_PCI_LABEL=y
>
> #
> # PCI host controller drivers
> #
> CONFIG_ISA_DMA_API=y
> CONFIG_AMD_NB=y
> CONFIG_PCCARD=y
> CONFIG_PCMCIA=y
> CONFIG_PCMCIA_LOAD_CIS=y
> CONFIG_CARDBUS=y
>
> #
> # PC-card bridges
> #
> CONFIG_YENTA=y
> CONFIG_YENTA_O2=y
> CONFIG_YENTA_RICOH=y
> CONFIG_YENTA_TI=y
> CONFIG_YENTA_ENE_TUNE=y
> CONFIG_YENTA_TOSHIBA=y
> # CONFIG_PD6729 is not set
> # CONFIG_I82092 is not set
> CONFIG_PCCARD_NONSTATIC=y
> CONFIG_HOTPLUG_PCI=y
> # CONFIG_HOTPLUG_PCI_ACPI is not set
> # CONFIG_HOTPLUG_PCI_CPCI is not set
> # CONFIG_HOTPLUG_PCI_SHPC is not set
> # CONFIG_RAPIDIO is not set
> # CONFIG_X86_SYSFB is not set
>
> #
> # Executable file formats / Emulations
> #
> CONFIG_BINFMT_ELF=y
> CONFIG_COMPAT_BINFMT_ELF=y
> CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS=y
> CONFIG_BINFMT_SCRIPT=y
> # CONFIG_HAVE_AOUT is not set
> CONFIG_BINFMT_MISC=y
> CONFIG_COREDUMP=y
> CONFIG_IA32_EMULATION=y
> # CONFIG_IA32_AOUT is not set
> # CONFIG_X86_X32 is not set
> CONFIG_COMPAT=y
> CONFIG_COMPAT_FOR_U64_ALIGNMENT=y
> CONFIG_SYSVIPC_COMPAT=y
> CONFIG_KEYS_COMPAT=y
> CONFIG_X86_DEV_DMA_OPS=y
> CONFIG_PMC_ATOM=y
> # CONFIG_VMD is not set
> CONFIG_NET=y
> CONFIG_NET_INGRESS=y
>
> #
> # Networking options
> #
> CONFIG_PACKET=y
> # CONFIG_PACKET_DIAG is not set
> CONFIG_UNIX=y
> # CONFIG_UNIX_DIAG is not set
> CONFIG_XFRM=y
> CONFIG_XFRM_ALGO=y
> CONFIG_XFRM_USER=y
> # CONFIG_XFRM_SUB_POLICY is not set
> # CONFIG_XFRM_MIGRATE is not set
> # CONFIG_XFRM_STATISTICS is not set
> # CONFIG_NET_KEY is not set
> CONFIG_INET=y
> CONFIG_IP_MULTICAST=y
> CONFIG_IP_ADVANCED_ROUTER=y
> # CONFIG_IP_FIB_TRIE_STATS is not set
> CONFIG_IP_MULTIPLE_TABLES=y
> CONFIG_IP_ROUTE_MULTIPATH=y
> CONFIG_IP_ROUTE_VERBOSE=y
> CONFIG_IP_PNP=y
> CONFIG_IP_PNP_DHCP=y
> CONFIG_IP_PNP_BOOTP=y
> CONFIG_IP_PNP_RARP=y
> # CONFIG_NET_IPIP is not set
> # CONFIG_NET_IPGRE_DEMUX is not set
> CONFIG_NET_IP_TUNNEL=y
> CONFIG_IP_MROUTE=y
> # CONFIG_IP_MROUTE_MULTIPLE_TABLES is not set
> CONFIG_IP_PIMSM_V1=y
> CONFIG_IP_PIMSM_V2=y
> CONFIG_SYN_COOKIES=y
> # CONFIG_NET_UDP_TUNNEL is not set
> # CONFIG_NET_FOU is not set
> # CONFIG_NET_FOU_IP_TUNNELS is not set
> # CONFIG_INET_AH is not set
> # CONFIG_INET_ESP is not set
> # CONFIG_INET_IPCOMP is not set
> # CONFIG_INET_XFRM_TUNNEL is not set
> CONFIG_INET_TUNNEL=y
> # CONFIG_INET_XFRM_MODE_TRANSPORT is not set
> # CONFIG_INET_XFRM_MODE_TUNNEL is not set
> # CONFIG_INET_XFRM_MODE_BEET is not set
> CONFIG_INET_LRO=y
> # CONFIG_INET_DIAG is not set
> CONFIG_TCP_CONG_ADVANCED=y
> # CONFIG_TCP_CONG_BIC is not set
> CONFIG_TCP_CONG_CUBIC=y
> # CONFIG_TCP_CONG_WESTWOOD is not set
> # CONFIG_TCP_CONG_HTCP is not set
> # CONFIG_TCP_CONG_HSTCP is not set
> # CONFIG_TCP_CONG_HYBLA is not set
> # CONFIG_TCP_CONG_VEGAS is not set
> # CONFIG_TCP_CONG_SCALABLE is not set
> # CONFIG_TCP_CONG_LP is not set
> # CONFIG_TCP_CONG_VENO is not set
> # CONFIG_TCP_CONG_YEAH is not set
> # CONFIG_TCP_CONG_ILLINOIS is not set
> # CONFIG_TCP_CONG_DCTCP is not set
> # CONFIG_TCP_CONG_CDG is not set
> CONFIG_DEFAULT_CUBIC=y
> # CONFIG_DEFAULT_RENO is not set
> CONFIG_DEFAULT_TCP_CONG="cubic"
> CONFIG_TCP_MD5SIG=y
> CONFIG_IPV6=y
> # CONFIG_IPV6_ROUTER_PREF is not set
> # CONFIG_IPV6_OPTIMISTIC_DAD is not set
> CONFIG_INET6_AH=y
> CONFIG_INET6_ESP=y
> # CONFIG_INET6_IPCOMP is not set
> # CONFIG_IPV6_MIP6 is not set
> # CONFIG_IPV6_ILA is not set
> # CONFIG_INET6_XFRM_TUNNEL is not set
> # CONFIG_INET6_TUNNEL is not set
> CONFIG_INET6_XFRM_MODE_TRANSPORT=y
> CONFIG_INET6_XFRM_MODE_TUNNEL=y
> CONFIG_INET6_XFRM_MODE_BEET=y
> # CONFIG_INET6_XFRM_MODE_ROUTEOPTIMIZATION is not set
> # CONFIG_IPV6_VTI is not set
> CONFIG_IPV6_SIT=y
> # CONFIG_IPV6_SIT_6RD is not set
> CONFIG_IPV6_NDISC_NODETYPE=y
> # CONFIG_IPV6_TUNNEL is not set
> # CONFIG_IPV6_GRE is not set
> # CONFIG_IPV6_MULTIPLE_TABLES is not set
> # CONFIG_IPV6_MROUTE is not set
> CONFIG_NETLABEL=y
> CONFIG_NETWORK_SECMARK=y
> CONFIG_NET_PTP_CLASSIFY=y
> # CONFIG_NETWORK_PHY_TIMESTAMPING is not set
> CONFIG_NETFILTER=y
> # CONFIG_NETFILTER_DEBUG is not set
> # CONFIG_NETFILTER_ADVANCED is not set
>
> #
> # Core Netfilter Configuration
> #
> CONFIG_NETFILTER_INGRESS=y
> CONFIG_NETFILTER_NETLINK=y
> CONFIG_NETFILTER_NETLINK_LOG=y
> CONFIG_NF_CONNTRACK=y
> CONFIG_NF_LOG_COMMON=m
> CONFIG_NF_CONNTRACK_SECMARK=y
> CONFIG_NF_CONNTRACK_PROCFS=y
> CONFIG_NF_CONNTRACK_FTP=y
> CONFIG_NF_CONNTRACK_IRC=y
> # CONFIG_NF_CONNTRACK_NETBIOS_NS is not set
> CONFIG_NF_CONNTRACK_SIP=y
> CONFIG_NF_CT_NETLINK=y
> # CONFIG_NETFILTER_NETLINK_GLUE_CT is not set
> CONFIG_NF_NAT=m
> CONFIG_NF_NAT_NEEDED=y
> # CONFIG_NF_NAT_AMANDA is not set
> CONFIG_NF_NAT_FTP=m
> CONFIG_NF_NAT_IRC=m
> CONFIG_NF_NAT_SIP=m
> # CONFIG_NF_NAT_TFTP is not set
> # CONFIG_NF_NAT_REDIRECT is not set
> # CONFIG_NF_TABLES is not set
> CONFIG_NETFILTER_XTABLES=y
>
> #
> # Xtables combined modules
> #
> CONFIG_NETFILTER_XT_MARK=m
>
> #
> # Xtables targets
> #
> CONFIG_NETFILTER_XT_TARGET_CONNSECMARK=y
> CONFIG_NETFILTER_XT_TARGET_LOG=m
> CONFIG_NETFILTER_XT_NAT=m
> # CONFIG_NETFILTER_XT_TARGET_NETMAP is not set
> CONFIG_NETFILTER_XT_TARGET_NFLOG=y
> # CONFIG_NETFILTER_XT_TARGET_REDIRECT is not set
> CONFIG_NETFILTER_XT_TARGET_SECMARK=y
> CONFIG_NETFILTER_XT_TARGET_TCPMSS=y
>
> #
> # Xtables matches
> #
> CONFIG_NETFILTER_XT_MATCH_ADDRTYPE=m
> CONFIG_NETFILTER_XT_MATCH_CONNTRACK=y
> CONFIG_NETFILTER_XT_MATCH_POLICY=y
> CONFIG_NETFILTER_XT_MATCH_STATE=y
> # CONFIG_IP_SET is not set
> # CONFIG_IP_VS is not set
>
> #
> # IP: Netfilter Configuration
> #
> CONFIG_NF_DEFRAG_IPV4=y
> CONFIG_NF_CONNTRACK_IPV4=y
> CONFIG_NF_CONNTRACK_PROC_COMPAT=y
> # CONFIG_NF_DUP_IPV4 is not set
> CONFIG_NF_LOG_ARP=m
> CONFIG_NF_LOG_IPV4=m
> CONFIG_NF_REJECT_IPV4=y
> CONFIG_NF_NAT_IPV4=m
> CONFIG_NF_NAT_MASQUERADE_IPV4=m
> # CONFIG_NF_NAT_PPTP is not set
> # CONFIG_NF_NAT_H323 is not set
> CONFIG_IP_NF_IPTABLES=y
> CONFIG_IP_NF_FILTER=y
> CONFIG_IP_NF_TARGET_REJECT=y
> CONFIG_IP_NF_NAT=m
> CONFIG_IP_NF_TARGET_MASQUERADE=m
> CONFIG_IP_NF_MANGLE=y
> # CONFIG_IP_NF_RAW is not set
>
> #
> # IPv6: Netfilter Configuration
> #
> CONFIG_NF_DEFRAG_IPV6=y
> CONFIG_NF_CONNTRACK_IPV6=y
> # CONFIG_NF_DUP_IPV6 is not set
> CONFIG_NF_REJECT_IPV6=y
> CONFIG_NF_LOG_IPV6=m
> CONFIG_IP6_NF_IPTABLES=y
> CONFIG_IP6_NF_MATCH_IPV6HEADER=y
> CONFIG_IP6_NF_FILTER=y
> CONFIG_IP6_NF_TARGET_REJECT=y
> CONFIG_IP6_NF_MANGLE=y
> # CONFIG_IP6_NF_RAW is not set
> # CONFIG_IP_DCCP is not set
> # CONFIG_IP_SCTP is not set
> # CONFIG_RDS is not set
> # CONFIG_TIPC is not set
> # CONFIG_ATM is not set
> # CONFIG_L2TP is not set
> # CONFIG_BRIDGE is not set
> CONFIG_HAVE_NET_DSA=y
> # CONFIG_VLAN_8021Q is not set
> # CONFIG_DECNET is not set
> # CONFIG_LLC2 is not set
> # CONFIG_IPX is not set
> # CONFIG_ATALK is not set
> # CONFIG_X25 is not set
> # CONFIG_LAPB is not set
> # CONFIG_PHONET is not set
> # CONFIG_6LOWPAN is not set
> # CONFIG_IEEE802154 is not set
> CONFIG_NET_SCHED=y
>
> #
> # Queueing/Scheduling
> #
> # CONFIG_NET_SCH_CBQ is not set
> # CONFIG_NET_SCH_HTB is not set
> # CONFIG_NET_SCH_HFSC is not set
> # CONFIG_NET_SCH_PRIO is not set
> # CONFIG_NET_SCH_MULTIQ is not set
> # CONFIG_NET_SCH_RED is not set
> # CONFIG_NET_SCH_SFB is not set
> # CONFIG_NET_SCH_SFQ is not set
> # CONFIG_NET_SCH_TEQL is not set
> # CONFIG_NET_SCH_TBF is not set
> # CONFIG_NET_SCH_GRED is not set
> # CONFIG_NET_SCH_DSMARK is not set
> # CONFIG_NET_SCH_NETEM is not set
> # CONFIG_NET_SCH_DRR is not set
> # CONFIG_NET_SCH_MQPRIO is not set
> # CONFIG_NET_SCH_CHOKE is not set
> # CONFIG_NET_SCH_QFQ is not set
> # CONFIG_NET_SCH_CODEL is not set
> # CONFIG_NET_SCH_FQ_CODEL is not set
> # CONFIG_NET_SCH_FQ is not set
> # CONFIG_NET_SCH_HHF is not set
> # CONFIG_NET_SCH_PIE is not set
> # CONFIG_NET_SCH_INGRESS is not set
> # CONFIG_NET_SCH_PLUG is not set
>
> #
> # Classification
> #
> CONFIG_NET_CLS=y
> # CONFIG_NET_CLS_BASIC is not set
> # CONFIG_NET_CLS_TCINDEX is not set
> # CONFIG_NET_CLS_ROUTE4 is not set
> # CONFIG_NET_CLS_FW is not set
> # CONFIG_NET_CLS_U32 is not set
> # CONFIG_NET_CLS_RSVP is not set
> # CONFIG_NET_CLS_RSVP6 is not set
> # CONFIG_NET_CLS_FLOW is not set
> # CONFIG_NET_CLS_CGROUP is not set
> # CONFIG_NET_CLS_BPF is not set
> # CONFIG_NET_CLS_FLOWER is not set
> CONFIG_NET_EMATCH=y
> CONFIG_NET_EMATCH_STACK=32
> # CONFIG_NET_EMATCH_CMP is not set
> # CONFIG_NET_EMATCH_NBYTE is not set
> # CONFIG_NET_EMATCH_U32 is not set
> # CONFIG_NET_EMATCH_META is not set
> # CONFIG_NET_EMATCH_TEXT is not set
> CONFIG_NET_CLS_ACT=y
> # CONFIG_NET_ACT_POLICE is not set
> # CONFIG_NET_ACT_GACT is not set
> # CONFIG_NET_ACT_MIRRED is not set
> # CONFIG_NET_ACT_IPT is not set
> # CONFIG_NET_ACT_NAT is not set
> # CONFIG_NET_ACT_PEDIT is not set
> # CONFIG_NET_ACT_SIMP is not set
> # CONFIG_NET_ACT_SKBEDIT is not set
> # CONFIG_NET_ACT_CSUM is not set
> # CONFIG_NET_ACT_VLAN is not set
> # CONFIG_NET_ACT_BPF is not set
> CONFIG_NET_SCH_FIFO=y
> # CONFIG_DCB is not set
> CONFIG_DNS_RESOLVER=y
> # CONFIG_BATMAN_ADV is not set
> # CONFIG_OPENVSWITCH is not set
> # CONFIG_VSOCKETS is not set
> # CONFIG_NETLINK_MMAP is not set
> # CONFIG_NETLINK_DIAG is not set
> # CONFIG_MPLS is not set
> # CONFIG_HSR is not set
> # CONFIG_NET_SWITCHDEV is not set
> # CONFIG_NET_L3_MASTER_DEV is not set
> CONFIG_RPS=y
> CONFIG_RFS_ACCEL=y
> CONFIG_XPS=y
> # CONFIG_SOCK_CGROUP_DATA is not set
> # CONFIG_CGROUP_NET_PRIO is not set
> # CONFIG_CGROUP_NET_CLASSID is not set
> CONFIG_NET_RX_BUSY_POLL=y
> CONFIG_BQL=y
> # CONFIG_BPF_JIT is not set
> CONFIG_NET_FLOW_LIMIT=y
>
> #
> # Network testing
> #
> # CONFIG_NET_PKTGEN is not set
> # CONFIG_NET_TCPPROBE is not set
> # CONFIG_NET_DROP_MONITOR is not set
> CONFIG_HAMRADIO=y
>
> #
> # Packet Radio protocols
> #
> # CONFIG_AX25 is not set
> # CONFIG_CAN is not set
> # CONFIG_IRDA is not set
> # CONFIG_BT is not set
> # CONFIG_AF_RXRPC is not set
> CONFIG_FIB_RULES=y
> CONFIG_WIRELESS=y
> CONFIG_CFG80211=y
> # CONFIG_NL80211_TESTMODE is not set
> # CONFIG_CFG80211_DEVELOPER_WARNINGS is not set
> # CONFIG_CFG80211_REG_DEBUG is not set
> CONFIG_CFG80211_DEFAULT_PS=y
> # CONFIG_CFG80211_DEBUGFS is not set
> # CONFIG_CFG80211_INTERNAL_REGDB is not set
> CONFIG_CFG80211_CRDA_SUPPORT=y
> # CONFIG_CFG80211_WEXT is not set
> # CONFIG_LIB80211 is not set
> CONFIG_MAC80211=y
> CONFIG_MAC80211_HAS_RC=y
> CONFIG_MAC80211_RC_MINSTREL=y
> CONFIG_MAC80211_RC_MINSTREL_HT=y
> # CONFIG_MAC80211_RC_MINSTREL_VHT is not set
> CONFIG_MAC80211_RC_DEFAULT_MINSTREL=y
> CONFIG_MAC80211_RC_DEFAULT="minstrel_ht"
> # CONFIG_MAC80211_MESH is not set
> CONFIG_MAC80211_LEDS=y
> # CONFIG_MAC80211_DEBUGFS is not set
> # CONFIG_MAC80211_MESSAGE_TRACING is not set
> # CONFIG_MAC80211_DEBUG_MENU is not set
> CONFIG_MAC80211_STA_HASH_MAX_SIZE=0
> # CONFIG_WIMAX is not set
> CONFIG_RFKILL=y
> CONFIG_RFKILL_LEDS=y
> CONFIG_RFKILL_INPUT=y
> # CONFIG_NET_9P is not set
> # CONFIG_CAIF is not set
> # CONFIG_CEPH_LIB is not set
> # CONFIG_NFC is not set
> # CONFIG_LWTUNNEL is not set
> CONFIG_HAVE_BPF_JIT=y
>
> #
> # Device Drivers
> #
>
> #
> # Generic Driver Options
> #
> CONFIG_UEVENT_HELPER=y
> CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
> CONFIG_DEVTMPFS=y
> CONFIG_DEVTMPFS_MOUNT=y
> CONFIG_STANDALONE=y
> CONFIG_PREVENT_FIRMWARE_BUILD=y
> CONFIG_FW_LOADER=y
> CONFIG_FIRMWARE_IN_KERNEL=y
> CONFIG_EXTRA_FIRMWARE=""
> # CONFIG_FW_LOADER_USER_HELPER_FALLBACK is not set
> CONFIG_ALLOW_DEV_COREDUMP=y
> # CONFIG_DEBUG_DRIVER is not set
> CONFIG_DEBUG_DEVRES=y
> # CONFIG_SYS_HYPERVISOR is not set
> # CONFIG_GENERIC_CPU_DEVICES is not set
> CONFIG_GENERIC_CPU_AUTOPROBE=y
> CONFIG_REGMAP=y
> CONFIG_DMA_SHARED_BUFFER=y
> # CONFIG_FENCE_TRACE is not set
>
> #
> # Bus devices
> #
> CONFIG_CONNECTOR=y
> CONFIG_PROC_EVENTS=y
> # CONFIG_MTD is not set
> # CONFIG_OF is not set
> CONFIG_ARCH_MIGHT_HAVE_PC_PARPORT=y
> # CONFIG_PARPORT is not set
> CONFIG_PNP=y
> CONFIG_PNP_DEBUG_MESSAGES=y
>
> #
> # Protocols
> #
> CONFIG_PNPACPI=y
> CONFIG_BLK_DEV=y
> # CONFIG_BLK_DEV_NULL_BLK is not set
> # CONFIG_BLK_DEV_FD is not set
> # CONFIG_BLK_DEV_PCIESSD_MTIP32XX is not set
> # CONFIG_BLK_CPQ_CISS_DA is not set
> # CONFIG_BLK_DEV_DAC960 is not set
> # CONFIG_BLK_DEV_UMEM is not set
> # CONFIG_BLK_DEV_COW_COMMON is not set
> CONFIG_BLK_DEV_LOOP=y
> CONFIG_BLK_DEV_LOOP_MIN_COUNT=8
> # CONFIG_BLK_DEV_CRYPTOLOOP is not set
> # CONFIG_BLK_DEV_DRBD is not set
> # CONFIG_BLK_DEV_NBD is not set
> # CONFIG_BLK_DEV_SKD is not set
> # CONFIG_BLK_DEV_SX8 is not set
> # CONFIG_BLK_DEV_RAM is not set
> # CONFIG_CDROM_PKTCDVD is not set
> # CONFIG_ATA_OVER_ETH is not set
> # CONFIG_BLK_DEV_HD is not set
> # CONFIG_BLK_DEV_RBD is not set
> # CONFIG_BLK_DEV_RSXX is not set
> # CONFIG_BLK_DEV_NVME is not set
>
> #
> # Misc devices
> #
> # CONFIG_SENSORS_LIS3LV02D is not set
> # CONFIG_AD525X_DPOT is not set
> # CONFIG_DUMMY_IRQ is not set
> # CONFIG_IBM_ASM is not set
> # CONFIG_PHANTOM is not set
> # CONFIG_SGI_IOC4 is not set
> # CONFIG_TIFM_CORE is not set
> # CONFIG_ICS932S401 is not set
> # CONFIG_ENCLOSURE_SERVICES is not set
> # CONFIG_HP_ILO is not set
> # CONFIG_APDS9802ALS is not set
> # CONFIG_ISL29003 is not set
> # CONFIG_ISL29020 is not set
> # CONFIG_SENSORS_TSL2550 is not set
> # CONFIG_SENSORS_BH1780 is not set
> # CONFIG_SENSORS_BH1770 is not set
> # CONFIG_SENSORS_APDS990X is not set
> # CONFIG_HMC6352 is not set
> # CONFIG_DS1682 is not set
> # CONFIG_BMP085_I2C is not set
> # CONFIG_USB_SWITCH_FSA9480 is not set
> # CONFIG_SRAM is not set
> # CONFIG_C2PORT is not set
>
> #
> # EEPROM support
> #
> # CONFIG_EEPROM_AT24 is not set
> # CONFIG_EEPROM_LEGACY is not set
> # CONFIG_EEPROM_MAX6875 is not set
> # CONFIG_EEPROM_93CX6 is not set
> # CONFIG_CB710_CORE is not set
>
> #
> # Texas Instruments shared transport line discipline
> #
> # CONFIG_SENSORS_LIS3_I2C is not set
>
> #
> # Altera FPGA firmware download module
> #
> # CONFIG_ALTERA_STAPL is not set
> # CONFIG_VMWARE_VMCI is not set
>
> #
> # Intel MIC Bus Driver
> #
> # CONFIG_INTEL_MIC_BUS is not set
>
> #
> # SCIF Bus Driver
> #
> # CONFIG_SCIF_BUS is not set
>
> #
> # Intel MIC Host Driver
> #
>
> #
> # Intel MIC Card Driver
> #
>
> #
> # SCIF Driver
> #
>
> #
> # Intel MIC Coprocessor State Management (COSM) Drivers
> #
> # CONFIG_GENWQE is not set
> # CONFIG_ECHO is not set
> # CONFIG_CXL_BASE is not set
> # CONFIG_CXL_KERNEL_API is not set
> # CONFIG_CXL_EEH is not set
> CONFIG_HAVE_IDE=y
> # CONFIG_IDE is not set
>
> #
> # SCSI device support
> #
> CONFIG_SCSI_MOD=y
> # CONFIG_RAID_ATTRS is not set
> CONFIG_SCSI=y
> CONFIG_SCSI_DMA=y
> # CONFIG_SCSI_NETLINK is not set
> # CONFIG_SCSI_MQ_DEFAULT is not set
> CONFIG_SCSI_PROC_FS=y
>
> #
> # SCSI support type (disk, tape, CD-ROM)
> #
> CONFIG_BLK_DEV_SD=y
> # CONFIG_CHR_DEV_ST is not set
> # CONFIG_CHR_DEV_OSST is not set
> CONFIG_BLK_DEV_SR=y
> CONFIG_BLK_DEV_SR_VENDOR=y
> CONFIG_CHR_DEV_SG=y
> # CONFIG_CHR_DEV_SCH is not set
> CONFIG_SCSI_CONSTANTS=y
> # CONFIG_SCSI_LOGGING is not set
> # CONFIG_SCSI_SCAN_ASYNC is not set
>
> #
> # SCSI Transports
> #
> CONFIG_SCSI_SPI_ATTRS=y
> # CONFIG_SCSI_FC_ATTRS is not set
> # CONFIG_SCSI_ISCSI_ATTRS is not set
> # CONFIG_SCSI_SAS_ATTRS is not set
> # CONFIG_SCSI_SAS_LIBSAS is not set
> # CONFIG_SCSI_SRP_ATTRS is not set
> # CONFIG_SCSI_LOWLEVEL is not set
> # CONFIG_SCSI_LOWLEVEL_PCMCIA is not set
> # CONFIG_SCSI_DH is not set
> # CONFIG_SCSI_OSD_INITIATOR is not set
> CONFIG_ATA=y
> # CONFIG_ATA_NONSTANDARD is not set
> CONFIG_ATA_VERBOSE_ERROR=y
> CONFIG_ATA_ACPI=y
> # CONFIG_SATA_ZPODD is not set
> CONFIG_SATA_PMP=y
>
> #
> # Controllers with non-SFF native interface
> #
> CONFIG_SATA_AHCI=y
> # CONFIG_SATA_AHCI_PLATFORM is not set
> # CONFIG_SATA_INIC162X is not set
> # CONFIG_SATA_ACARD_AHCI is not set
> # CONFIG_SATA_SIL24 is not set
> CONFIG_ATA_SFF=y
>
> #
> # SFF controllers with custom DMA interface
> #
> # CONFIG_PDC_ADMA is not set
> # CONFIG_SATA_QSTOR is not set
> # CONFIG_SATA_SX4 is not set
> CONFIG_ATA_BMDMA=y
>
> #
> # SATA SFF controllers with BMDMA
> #
> CONFIG_ATA_PIIX=y
> # CONFIG_SATA_MV is not set
> # CONFIG_SATA_NV is not set
> # CONFIG_SATA_PROMISE is not set
> # CONFIG_SATA_SIL is not set
> # CONFIG_SATA_SIS is not set
> # CONFIG_SATA_SVW is not set
> # CONFIG_SATA_ULI is not set
> # CONFIG_SATA_VIA is not set
> # CONFIG_SATA_VITESSE is not set
>
> #
> # PATA SFF controllers with BMDMA
> #
> # CONFIG_PATA_ALI is not set
> CONFIG_PATA_AMD=y
> # CONFIG_PATA_ARTOP is not set
> # CONFIG_PATA_ATIIXP is not set
> # CONFIG_PATA_ATP867X is not set
> # CONFIG_PATA_CMD64X is not set
> # CONFIG_PATA_CYPRESS is not set
> # CONFIG_PATA_EFAR is not set
> # CONFIG_PATA_HPT366 is not set
> # CONFIG_PATA_HPT37X is not set
> # CONFIG_PATA_HPT3X2N is not set
> # CONFIG_PATA_HPT3X3 is not set
> # CONFIG_PATA_IT8213 is not set
> # CONFIG_PATA_IT821X is not set
> # CONFIG_PATA_JMICRON is not set
> # CONFIG_PATA_MARVELL is not set
> # CONFIG_PATA_NETCELL is not set
> # CONFIG_PATA_NINJA32 is not set
> # CONFIG_PATA_NS87415 is not set
> CONFIG_PATA_OLDPIIX=y
> # CONFIG_PATA_OPTIDMA is not set
> # CONFIG_PATA_PDC2027X is not set
> # CONFIG_PATA_PDC_OLD is not set
> # CONFIG_PATA_RADISYS is not set
> # CONFIG_PATA_RDC is not set
> CONFIG_PATA_SCH=y
> # CONFIG_PATA_SERVERWORKS is not set
> # CONFIG_PATA_SIL680 is not set
> # CONFIG_PATA_SIS is not set
> # CONFIG_PATA_TOSHIBA is not set
> # CONFIG_PATA_TRIFLEX is not set
> # CONFIG_PATA_VIA is not set
> # CONFIG_PATA_WINBOND is not set
>
> #
> # PIO-only SFF controllers
> #
> # CONFIG_PATA_CMD640_PCI is not set
> # CONFIG_PATA_MPIIX is not set
> # CONFIG_PATA_NS87410 is not set
> # CONFIG_PATA_OPTI is not set
> # CONFIG_PATA_PCMCIA is not set
> # CONFIG_PATA_RZ1000 is not set
>
> #
> # Generic fallback / legacy drivers
> #
> # CONFIG_PATA_ACPI is not set
> # CONFIG_ATA_GENERIC is not set
> # CONFIG_PATA_LEGACY is not set
> CONFIG_MD=y
> CONFIG_BLK_DEV_MD=y
> CONFIG_MD_AUTODETECT=y
> # CONFIG_MD_LINEAR is not set
> # CONFIG_MD_RAID0 is not set
> # CONFIG_MD_RAID1 is not set
> # CONFIG_MD_RAID10 is not set
> # CONFIG_MD_RAID456 is not set
> # CONFIG_MD_MULTIPATH is not set
> # CONFIG_MD_FAULTY is not set
> # CONFIG_BCACHE is not set
> CONFIG_BLK_DEV_DM_BUILTIN=y
> CONFIG_BLK_DEV_DM=y
> # CONFIG_DM_MQ_DEFAULT is not set
> # CONFIG_DM_DEBUG is not set
> # CONFIG_DM_CRYPT is not set
> # CONFIG_DM_SNAPSHOT is not set
> # CONFIG_DM_THIN_PROVISIONING is not set
> # CONFIG_DM_CACHE is not set
> # CONFIG_DM_ERA is not set
> CONFIG_DM_MIRROR=y
> # CONFIG_DM_LOG_USERSPACE is not set
> # CONFIG_DM_RAID is not set
> CONFIG_DM_ZERO=y
> # CONFIG_DM_MULTIPATH is not set
> # CONFIG_DM_DELAY is not set
> # CONFIG_DM_UEVENT is not set
> # CONFIG_DM_FLAKEY is not set
> # CONFIG_DM_VERITY is not set
> # CONFIG_DM_SWITCH is not set
> # CONFIG_DM_LOG_WRITES is not set
> # CONFIG_TARGET_CORE is not set
> # CONFIG_FUSION is not set
>
> #
> # IEEE 1394 (FireWire) support
> #
> # CONFIG_FIREWIRE is not set
> # CONFIG_FIREWIRE_NOSY is not set
> CONFIG_MACINTOSH_DRIVERS=y
> CONFIG_MAC_EMUMOUSEBTN=y
> CONFIG_NETDEVICES=y
> CONFIG_MII=y
> CONFIG_NET_CORE=y
> # CONFIG_BONDING is not set
> # CONFIG_DUMMY is not set
> # CONFIG_EQUALIZER is not set
> # CONFIG_NET_FC is not set
> # CONFIG_IFB is not set
> # CONFIG_NET_TEAM is not set
> # CONFIG_MACVLAN is not set
> # CONFIG_IPVLAN is not set
> # CONFIG_VXLAN is not set
> CONFIG_NETCONSOLE=y
> CONFIG_NETPOLL=y
> CONFIG_NET_POLL_CONTROLLER=y
> # CONFIG_TUN is not set
> # CONFIG_TUN_VNET_CROSS_LE is not set
> # CONFIG_VETH is not set
> # CONFIG_NLMON is not set
> # CONFIG_ARCNET is not set
>
> #
> # CAIF transport drivers
> #
> # CONFIG_VHOST_NET is not set
> # CONFIG_VHOST_CROSS_ENDIAN_LEGACY is not set
>
> #
> # Distributed Switch Architecture drivers
> #
> # CONFIG_NET_DSA_MV88E6XXX is not set
> # CONFIG_NET_DSA_MV88E6XXX_NEED_PPU is not set
> CONFIG_ETHERNET=y
> CONFIG_NET_VENDOR_3COM=y
> # CONFIG_PCMCIA_3C574 is not set
> # CONFIG_PCMCIA_3C589 is not set
> # CONFIG_VORTEX is not set
> # CONFIG_TYPHOON is not set
> CONFIG_NET_VENDOR_ADAPTEC=y
> # CONFIG_ADAPTEC_STARFIRE is not set
> CONFIG_NET_VENDOR_AGERE=y
> # CONFIG_ET131X is not set
> CONFIG_NET_VENDOR_ALTEON=y
> # CONFIG_ACENIC is not set
> # CONFIG_ALTERA_TSE is not set
> CONFIG_NET_VENDOR_AMD=y
> # CONFIG_AMD8111_ETH is not set
> # CONFIG_PCNET32 is not set
> # CONFIG_PCMCIA_NMCLAN is not set
> CONFIG_NET_VENDOR_ARC=y
> CONFIG_NET_VENDOR_ATHEROS=y
> # CONFIG_ATL2 is not set
> # CONFIG_ATL1 is not set
> # CONFIG_ATL1E is not set
> # CONFIG_ATL1C is not set
> # CONFIG_ALX is not set
> # CONFIG_NET_VENDOR_AURORA is not set
> CONFIG_NET_CADENCE=y
> # CONFIG_MACB is not set
> CONFIG_NET_VENDOR_BROADCOM=y
> # CONFIG_B44 is not set
> # CONFIG_BCMGENET is not set
> # CONFIG_BNX2 is not set
> # CONFIG_CNIC is not set
> CONFIG_TIGON3=y
> # CONFIG_BNX2X is not set
> # CONFIG_BNXT is not set
> CONFIG_NET_VENDOR_BROCADE=y
> # CONFIG_BNA is not set
> CONFIG_NET_VENDOR_CAVIUM=y
> # CONFIG_THUNDER_NIC_PF is not set
> # CONFIG_THUNDER_NIC_VF is not set
> # CONFIG_THUNDER_NIC_BGX is not set
> # CONFIG_LIQUIDIO is not set
> CONFIG_NET_VENDOR_CHELSIO=y
> # CONFIG_CHELSIO_T1 is not set
> # CONFIG_CHELSIO_T3 is not set
> # CONFIG_CHELSIO_T4 is not set
> # CONFIG_CHELSIO_T4VF is not set
> CONFIG_NET_VENDOR_CISCO=y
> # CONFIG_ENIC is not set
> # CONFIG_CX_ECAT is not set
> # CONFIG_DNET is not set
> CONFIG_NET_VENDOR_DEC=y
> CONFIG_NET_TULIP=y
> # CONFIG_DE2104X is not set
> # CONFIG_TULIP is not set
> # CONFIG_DE4X5 is not set
> # CONFIG_WINBOND_840 is not set
> # CONFIG_DM9102 is not set
> # CONFIG_ULI526X is not set
> # CONFIG_PCMCIA_XIRCOM is not set
> CONFIG_NET_VENDOR_DLINK=y
> # CONFIG_DL2K is not set
> # CONFIG_SUNDANCE is not set
> CONFIG_NET_VENDOR_EMULEX=y
> # CONFIG_BE2NET is not set
> CONFIG_NET_VENDOR_EZCHIP=y
> CONFIG_NET_VENDOR_EXAR=y
> # CONFIG_S2IO is not set
> # CONFIG_VXGE is not set
> CONFIG_NET_VENDOR_FUJITSU=y
> # CONFIG_PCMCIA_FMVJ18X is not set
> CONFIG_NET_VENDOR_HP=y
> # CONFIG_HP100 is not set
> CONFIG_NET_VENDOR_INTEL=y
> CONFIG_E100=y
> CONFIG_E1000=y
> # CONFIG_E1000E is not set
> # CONFIG_IGB is not set
> # CONFIG_IGBVF is not set
> # CONFIG_IXGB is not set
> # CONFIG_IXGBE is not set
> # CONFIG_IXGBEVF is not set
> # CONFIG_I40E is not set
> # CONFIG_I40EVF is not set
> # CONFIG_FM10K is not set
> CONFIG_NET_VENDOR_I825XX=y
> # CONFIG_JME is not set
> CONFIG_NET_VENDOR_MARVELL=y
> # CONFIG_MVMDIO is not set
> # CONFIG_SKGE is not set
> CONFIG_SKY2=y
> # CONFIG_SKY2_DEBUG is not set
> CONFIG_NET_VENDOR_MELLANOX=y
> # CONFIG_MLX4_EN is not set
> # CONFIG_MLX4_CORE is not set
> # CONFIG_MLX5_CORE is not set
> # CONFIG_MLXSW_CORE is not set
> CONFIG_NET_VENDOR_MICREL=y
> # CONFIG_KS8851_MLL is not set
> # CONFIG_KSZ884X_PCI is not set
> CONFIG_NET_VENDOR_MYRI=y
> # CONFIG_MYRI10GE is not set
> # CONFIG_FEALNX is not set
> CONFIG_NET_VENDOR_NATSEMI=y
> # CONFIG_NATSEMI is not set
> # CONFIG_NS83820 is not set
> CONFIG_NET_VENDOR_NETRONOME=y
> # CONFIG_NFP_NETVF is not set
> CONFIG_NET_VENDOR_8390=y
> # CONFIG_PCMCIA_AXNET is not set
> # CONFIG_NE2K_PCI is not set
> # CONFIG_PCMCIA_PCNET is not set
> CONFIG_NET_VENDOR_NVIDIA=y
> CONFIG_FORCEDETH=y
> CONFIG_NET_VENDOR_OKI=y
> # CONFIG_ETHOC is not set
> CONFIG_NET_PACKET_ENGINE=y
> # CONFIG_HAMACHI is not set
> # CONFIG_YELLOWFIN is not set
> CONFIG_NET_VENDOR_QLOGIC=y
> # CONFIG_QLA3XXX is not set
> # CONFIG_QLCNIC is not set
> # CONFIG_QLGE is not set
> # CONFIG_NETXEN_NIC is not set
> # CONFIG_QED is not set
> CONFIG_NET_VENDOR_QUALCOMM=y
> CONFIG_NET_VENDOR_REALTEK=y
> # CONFIG_8139CP is not set
> CONFIG_8139TOO=y
> CONFIG_8139TOO_PIO=y
> # CONFIG_8139TOO_TUNE_TWISTER is not set
> # CONFIG_8139TOO_8129 is not set
> # CONFIG_8139_OLD_RX_RESET is not set
> # CONFIG_R8169 is not set
> CONFIG_NET_VENDOR_RENESAS=y
> CONFIG_NET_VENDOR_RDC=y
> # CONFIG_R6040 is not set
> CONFIG_NET_VENDOR_ROCKER=y
> CONFIG_NET_VENDOR_SAMSUNG=y
> # CONFIG_SXGBE_ETH is not set
> CONFIG_NET_VENDOR_SEEQ=y
> CONFIG_NET_VENDOR_SILAN=y
> # CONFIG_SC92031 is not set
> CONFIG_NET_VENDOR_SIS=y
> # CONFIG_SIS900 is not set
> # CONFIG_SIS190 is not set
> # CONFIG_SFC is not set
> CONFIG_NET_VENDOR_SMSC=y
> # CONFIG_PCMCIA_SMC91C92 is not set
> # CONFIG_EPIC100 is not set
> # CONFIG_SMSC911X is not set
> # CONFIG_SMSC9420 is not set
> CONFIG_NET_VENDOR_STMICRO=y
> # CONFIG_STMMAC_ETH is not set
> CONFIG_NET_VENDOR_SUN=y
> # CONFIG_HAPPYMEAL is not set
> # CONFIG_SUNGEM is not set
> # CONFIG_CASSINI is not set
> # CONFIG_NIU is not set
> CONFIG_NET_VENDOR_SYNOPSYS=y
> CONFIG_NET_VENDOR_TEHUTI=y
> # CONFIG_TEHUTI is not set
> CONFIG_NET_VENDOR_TI=y
> # CONFIG_TI_CPSW_ALE is not set
> # CONFIG_TLAN is not set
> CONFIG_NET_VENDOR_VIA=y
> # CONFIG_VIA_RHINE is not set
> # CONFIG_VIA_VELOCITY is not set
> CONFIG_NET_VENDOR_WIZNET=y
> # CONFIG_WIZNET_W5100 is not set
> # CONFIG_WIZNET_W5300 is not set
> CONFIG_NET_VENDOR_XIRCOM=y
> # CONFIG_PCMCIA_XIRC2PS is not set
> CONFIG_FDDI=y
> # CONFIG_DEFXX is not set
> # CONFIG_SKFP is not set
> # CONFIG_HIPPI is not set
> # CONFIG_NET_SB1000 is not set
> CONFIG_PHYLIB=y
>
> #
> # MII PHY device drivers
> #
> # CONFIG_AQUANTIA_PHY is not set
> # CONFIG_AT803X_PHY is not set
> # CONFIG_AMD_PHY is not set
> # CONFIG_MARVELL_PHY is not set
> # CONFIG_DAVICOM_PHY is not set
> # CONFIG_QSEMI_PHY is not set
> # CONFIG_LXT_PHY is not set
> # CONFIG_CICADA_PHY is not set
> # CONFIG_VITESSE_PHY is not set
> # CONFIG_TERANETICS_PHY is not set
> # CONFIG_SMSC_PHY is not set
> # CONFIG_BROADCOM_PHY is not set
> # CONFIG_BCM7XXX_PHY is not set
> # CONFIG_BCM87XX_PHY is not set
> # CONFIG_ICPLUS_PHY is not set
> # CONFIG_REALTEK_PHY is not set
> # CONFIG_NATIONAL_PHY is not set
> # CONFIG_STE10XP is not set
> # CONFIG_LSI_ET1011C_PHY is not set
> # CONFIG_MICREL_PHY is not set
> # CONFIG_DP83848_PHY is not set
> # CONFIG_DP83867_PHY is not set
> # CONFIG_MICROCHIP_PHY is not set
> # CONFIG_FIXED_PHY is not set
> # CONFIG_MDIO_BITBANG is not set
> # CONFIG_MDIO_OCTEON is not set
> # CONFIG_MDIO_BCM_UNIMAC is not set
> # CONFIG_PPP is not set
> # CONFIG_SLIP is not set
> CONFIG_USB_NET_DRIVERS=y
> # CONFIG_USB_CATC is not set
> # CONFIG_USB_KAWETH is not set
> # CONFIG_USB_PEGASUS is not set
> # CONFIG_USB_RTL8150 is not set
> # CONFIG_USB_RTL8152 is not set
> # CONFIG_USB_LAN78XX is not set
> # CONFIG_USB_USBNET is not set
> # CONFIG_USB_HSO is not set
> # CONFIG_USB_IPHETH is not set
> CONFIG_WLAN=y
> CONFIG_WLAN_VENDOR_ADMTEK=y
> # CONFIG_ADM8211 is not set
> CONFIG_WLAN_VENDOR_ATH=y
> # CONFIG_ATH_DEBUG is not set
> # CONFIG_ATH5K is not set
> # CONFIG_ATH5K_PCI is not set
> # CONFIG_ATH9K is not set
> # CONFIG_ATH9K_HTC is not set
> # CONFIG_CARL9170 is not set
> # CONFIG_ATH6KL is not set
> # CONFIG_AR5523 is not set
> # CONFIG_WIL6210 is not set
> # CONFIG_ATH10K is not set
> # CONFIG_WCN36XX is not set
> CONFIG_WLAN_VENDOR_ATMEL=y
> # CONFIG_ATMEL is not set
> # CONFIG_AT76C50X_USB is not set
> CONFIG_WLAN_VENDOR_BROADCOM=y
> # CONFIG_B43 is not set
> # CONFIG_B43LEGACY is not set
> # CONFIG_BRCMSMAC is not set
> # CONFIG_BRCMFMAC is not set
> CONFIG_WLAN_VENDOR_CISCO=y
> # CONFIG_AIRO is not set
> # CONFIG_AIRO_CS is not set
> CONFIG_WLAN_VENDOR_INTEL=y
> # CONFIG_IPW2100 is not set
> # CONFIG_IPW2200 is not set
> # CONFIG_IWL4965 is not set
> # CONFIG_IWL3945 is not set
> # CONFIG_IWLWIFI is not set
> CONFIG_WLAN_VENDOR_INTERSIL=y
> # CONFIG_HOSTAP is not set
> # CONFIG_HERMES is not set
> # CONFIG_P54_COMMON is not set
> # CONFIG_PRISM54 is not set
> CONFIG_WLAN_VENDOR_MARVELL=y
> # CONFIG_LIBERTAS is not set
> # CONFIG_LIBERTAS_THINFIRM is not set
> # CONFIG_MWIFIEX is not set
> # CONFIG_MWL8K is not set
> CONFIG_WLAN_VENDOR_MEDIATEK=y
> # CONFIG_MT7601U is not set
> CONFIG_WLAN_VENDOR_RALINK=y
> # CONFIG_RT2X00 is not set
> CONFIG_WLAN_VENDOR_REALTEK=y
> # CONFIG_RTL8180 is not set
> # CONFIG_RTL8187 is not set
> CONFIG_RTL_CARDS=y
> # CONFIG_RTL8192CE is not set
> # CONFIG_RTL8192SE is not set
> # CONFIG_RTL8192DE is not set
> # CONFIG_RTL8723AE is not set
> # CONFIG_RTL8723BE is not set
> # CONFIG_RTL8188EE is not set
> # CONFIG_RTL8192EE is not set
> # CONFIG_RTL8821AE is not set
> # CONFIG_RTL8192CU is not set
> # CONFIG_RTL8XXXU is not set
> CONFIG_WLAN_VENDOR_RSI=y
> # CONFIG_RSI_91X is not set
> CONFIG_WLAN_VENDOR_ST=y
> # CONFIG_CW1200 is not set
> CONFIG_WLAN_VENDOR_TI=y
> # CONFIG_WL1251 is not set
> # CONFIG_WL12XX is not set
> # CONFIG_WL18XX is not set
> # CONFIG_WLCORE is not set
> CONFIG_WLAN_VENDOR_ZYDAS=y
> # CONFIG_USB_ZD1201 is not set
> # CONFIG_ZD1211RW is not set
> # CONFIG_PCMCIA_RAYCS is not set
> # CONFIG_PCMCIA_WL3501 is not set
> # CONFIG_MAC80211_HWSIM is not set
> # CONFIG_USB_NET_RNDIS_WLAN is not set
>
> #
> # Enable WiMAX (Networking options) to see the WiMAX drivers
> #
> # CONFIG_WAN is not set
> # CONFIG_VMXNET3 is not set
> # CONFIG_FUJITSU_ES is not set
> # CONFIG_ISDN is not set
> # CONFIG_NVM is not set
>
> #
> # Input device support
> #
> CONFIG_INPUT=y
> CONFIG_INPUT_LEDS=y
> CONFIG_INPUT_FF_MEMLESS=y
> CONFIG_INPUT_POLLDEV=y
> CONFIG_INPUT_SPARSEKMAP=y
> # CONFIG_INPUT_MATRIXKMAP is not set
>
> #
> # Userland interfaces
> #
> CONFIG_INPUT_MOUSEDEV=y
> # CONFIG_INPUT_MOUSEDEV_PSAUX is not set
> CONFIG_INPUT_MOUSEDEV_SCREEN_X=1024
> CONFIG_INPUT_MOUSEDEV_SCREEN_Y=768
> # CONFIG_INPUT_JOYDEV is not set
> CONFIG_INPUT_EVDEV=y
> # CONFIG_INPUT_EVBUG is not set
>
> #
> # Input Device Drivers
> #
> CONFIG_INPUT_KEYBOARD=y
> # CONFIG_KEYBOARD_ADP5588 is not set
> # CONFIG_KEYBOARD_ADP5589 is not set
> CONFIG_KEYBOARD_ATKBD=y
> # CONFIG_KEYBOARD_QT1070 is not set
> # CONFIG_KEYBOARD_QT2160 is not set
> # CONFIG_KEYBOARD_LKKBD is not set
> # CONFIG_KEYBOARD_TCA6416 is not set
> # CONFIG_KEYBOARD_TCA8418 is not set
> # CONFIG_KEYBOARD_LM8323 is not set
> # CONFIG_KEYBOARD_LM8333 is not set
> # CONFIG_KEYBOARD_MAX7359 is not set
> # CONFIG_KEYBOARD_MCS is not set
> # CONFIG_KEYBOARD_MPR121 is not set
> # CONFIG_KEYBOARD_NEWTON is not set
> # CONFIG_KEYBOARD_OPENCORES is not set
> # CONFIG_KEYBOARD_STOWAWAY is not set
> # CONFIG_KEYBOARD_SUNKBD is not set
> # CONFIG_KEYBOARD_XTKBD is not set
> CONFIG_INPUT_MOUSE=y
> CONFIG_MOUSE_PS2=y
> CONFIG_MOUSE_PS2_ALPS=y
> CONFIG_MOUSE_PS2_LOGIPS2PP=y
> CONFIG_MOUSE_PS2_SYNAPTICS=y
> CONFIG_MOUSE_PS2_CYPRESS=y
> CONFIG_MOUSE_PS2_LIFEBOOK=y
> CONFIG_MOUSE_PS2_TRACKPOINT=y
> # CONFIG_MOUSE_PS2_ELANTECH is not set
> # CONFIG_MOUSE_PS2_SENTELIC is not set
> # CONFIG_MOUSE_PS2_TOUCHKIT is not set
> CONFIG_MOUSE_PS2_FOCALTECH=y
> # CONFIG_MOUSE_SERIAL is not set
> # CONFIG_MOUSE_APPLETOUCH is not set
> # CONFIG_MOUSE_BCM5974 is not set
> # CONFIG_MOUSE_CYAPA is not set
> # CONFIG_MOUSE_ELAN_I2C is not set
> # CONFIG_MOUSE_VSXXXAA is not set
> # CONFIG_MOUSE_SYNAPTICS_I2C is not set
> # CONFIG_MOUSE_SYNAPTICS_USB is not set
> CONFIG_INPUT_JOYSTICK=y
> # CONFIG_JOYSTICK_ANALOG is not set
> # CONFIG_JOYSTICK_A3D is not set
> # CONFIG_JOYSTICK_ADI is not set
> # CONFIG_JOYSTICK_COBRA is not set
> # CONFIG_JOYSTICK_GF2K is not set
> # CONFIG_JOYSTICK_GRIP is not set
> # CONFIG_JOYSTICK_GRIP_MP is not set
> # CONFIG_JOYSTICK_GUILLEMOT is not set
> # CONFIG_JOYSTICK_INTERACT is not set
> # CONFIG_JOYSTICK_SIDEWINDER is not set
> # CONFIG_JOYSTICK_TMDC is not set
> # CONFIG_JOYSTICK_IFORCE is not set
> # CONFIG_JOYSTICK_WARRIOR is not set
> # CONFIG_JOYSTICK_MAGELLAN is not set
> # CONFIG_JOYSTICK_SPACEORB is not set
> # CONFIG_JOYSTICK_SPACEBALL is not set
> # CONFIG_JOYSTICK_STINGER is not set
> # CONFIG_JOYSTICK_TWIDJOY is not set
> # CONFIG_JOYSTICK_ZHENHUA is not set
> # CONFIG_JOYSTICK_AS5011 is not set
> # CONFIG_JOYSTICK_JOYDUMP is not set
> # CONFIG_JOYSTICK_XPAD is not set
> CONFIG_INPUT_TABLET=y
> # CONFIG_TABLET_USB_ACECAD is not set
> # CONFIG_TABLET_USB_AIPTEK is not set
> # CONFIG_TABLET_USB_GTCO is not set
> # CONFIG_TABLET_USB_HANWANG is not set
> # CONFIG_TABLET_USB_KBTAB is not set
> # CONFIG_TABLET_SERIAL_WACOM4 is not set
> CONFIG_INPUT_TOUCHSCREEN=y
> CONFIG_TOUCHSCREEN_PROPERTIES=y
> # CONFIG_TOUCHSCREEN_AD7879 is not set
> # CONFIG_TOUCHSCREEN_ATMEL_MXT is not set
> # CONFIG_TOUCHSCREEN_BU21013 is not set
> # CONFIG_TOUCHSCREEN_CYTTSP_CORE is not set
> # CONFIG_TOUCHSCREEN_CYTTSP4_CORE is not set
> # CONFIG_TOUCHSCREEN_DYNAPRO is not set
> # CONFIG_TOUCHSCREEN_HAMPSHIRE is not set
> # CONFIG_TOUCHSCREEN_EETI is not set
> # CONFIG_TOUCHSCREEN_EGALAX_SERIAL is not set
> # CONFIG_TOUCHSCREEN_FUJITSU is not set
> # CONFIG_TOUCHSCREEN_ILI210X is not set
> # CONFIG_TOUCHSCREEN_GUNZE is not set
> # CONFIG_TOUCHSCREEN_ELAN is not set
> # CONFIG_TOUCHSCREEN_ELO is not set
> # CONFIG_TOUCHSCREEN_WACOM_W8001 is not set
> # CONFIG_TOUCHSCREEN_WACOM_I2C is not set
> # CONFIG_TOUCHSCREEN_MAX11801 is not set
> # CONFIG_TOUCHSCREEN_MCS5000 is not set
> # CONFIG_TOUCHSCREEN_MMS114 is not set
> # CONFIG_TOUCHSCREEN_MTOUCH is not set
> # CONFIG_TOUCHSCREEN_INEXIO is not set
> # CONFIG_TOUCHSCREEN_MK712 is not set
> # CONFIG_TOUCHSCREEN_PENMOUNT is not set
> # CONFIG_TOUCHSCREEN_EDT_FT5X06 is not set
> # CONFIG_TOUCHSCREEN_TOUCHRIGHT is not set
> # CONFIG_TOUCHSCREEN_TOUCHWIN is not set
> # CONFIG_TOUCHSCREEN_PIXCIR is not set
> # CONFIG_TOUCHSCREEN_WDT87XX_I2C is not set
> # CONFIG_TOUCHSCREEN_USB_COMPOSITE is not set
> # CONFIG_TOUCHSCREEN_TOUCHIT213 is not set
> # CONFIG_TOUCHSCREEN_TSC_SERIO is not set
> # CONFIG_TOUCHSCREEN_TSC2004 is not set
> # CONFIG_TOUCHSCREEN_TSC2007 is not set
> # CONFIG_TOUCHSCREEN_ST1232 is not set
> # CONFIG_TOUCHSCREEN_SX8654 is not set
> # CONFIG_TOUCHSCREEN_TPS6507X is not set
> # CONFIG_TOUCHSCREEN_ROHM_BU21023 is not set
> CONFIG_INPUT_MISC=y
> # CONFIG_INPUT_AD714X is not set
> # CONFIG_INPUT_BMA150 is not set
> # CONFIG_INPUT_E3X0_BUTTON is not set
> # CONFIG_INPUT_PCSPKR is not set
> # CONFIG_INPUT_MMA8450 is not set
> # CONFIG_INPUT_MPU3050 is not set
> # CONFIG_INPUT_APANEL is not set
> # CONFIG_INPUT_ATLAS_BTNS is not set
> # CONFIG_INPUT_ATI_REMOTE2 is not set
> # CONFIG_INPUT_KEYSPAN_REMOTE is not set
> # CONFIG_INPUT_KXTJ9 is not set
> # CONFIG_INPUT_POWERMATE is not set
> # CONFIG_INPUT_YEALINK is not set
> # CONFIG_INPUT_CM109 is not set
> # CONFIG_INPUT_UINPUT is not set
> # CONFIG_INPUT_PCF8574 is not set
> # CONFIG_INPUT_ADXL34X is not set
> # CONFIG_INPUT_IMS_PCU is not set
> # CONFIG_INPUT_CMA3000 is not set
> # CONFIG_INPUT_IDEAPAD_SLIDEBAR is not set
> # CONFIG_INPUT_DRV2665_HAPTICS is not set
> # CONFIG_INPUT_DRV2667_HAPTICS is not set
>
> #
> # Hardware I/O ports
> #
> CONFIG_SERIO=y
> CONFIG_ARCH_MIGHT_HAVE_PC_SERIO=y
> CONFIG_SERIO_I8042=y
> CONFIG_SERIO_SERPORT=y
> # CONFIG_SERIO_CT82C710 is not set
> # CONFIG_SERIO_PCIPS2 is not set
> CONFIG_SERIO_LIBPS2=y
> # CONFIG_SERIO_RAW is not set
> # CONFIG_SERIO_ALTERA_PS2 is not set
> # CONFIG_SERIO_PS2MULT is not set
> # CONFIG_SERIO_ARC_PS2 is not set
> # CONFIG_USERIO is not set
> # CONFIG_GAMEPORT is not set
>
> #
> # Character devices
> #
> CONFIG_TTY=y
> CONFIG_VT=y
> CONFIG_CONSOLE_TRANSLATIONS=y
> CONFIG_VT_CONSOLE=y
> CONFIG_VT_CONSOLE_SLEEP=y
> CONFIG_HW_CONSOLE=y
> CONFIG_VT_HW_CONSOLE_BINDING=y
> CONFIG_UNIX98_PTYS=y
> # CONFIG_DEVPTS_MULTIPLE_INSTANCES is not set
> # CONFIG_LEGACY_PTYS is not set
> CONFIG_SERIAL_NONSTANDARD=y
> # CONFIG_ROCKETPORT is not set
> # CONFIG_CYCLADES is not set
> # CONFIG_MOXA_INTELLIO is not set
> # CONFIG_MOXA_SMARTIO is not set
> # CONFIG_SYNCLINK is not set
> # CONFIG_SYNCLINKMP is not set
> # CONFIG_SYNCLINK_GT is not set
> # CONFIG_NOZOMI is not set
> # CONFIG_ISI is not set
> # CONFIG_N_HDLC is not set
> # CONFIG_N_GSM is not set
> # CONFIG_TRACE_SINK is not set
> CONFIG_DEVMEM=y
> CONFIG_DEVKMEM=y
>
> #
> # Serial drivers
> #
> CONFIG_SERIAL_EARLYCON=y
> CONFIG_SERIAL_8250=y
> CONFIG_SERIAL_8250_DEPRECATED_OPTIONS=y
> CONFIG_SERIAL_8250_PNP=y
> CONFIG_SERIAL_8250_CONSOLE=y
> CONFIG_SERIAL_8250_DMA=y
> CONFIG_SERIAL_8250_PCI=y
> # CONFIG_SERIAL_8250_CS is not set
> CONFIG_SERIAL_8250_NR_UARTS=32
> CONFIG_SERIAL_8250_RUNTIME_UARTS=4
> CONFIG_SERIAL_8250_EXTENDED=y
> CONFIG_SERIAL_8250_MANY_PORTS=y
> CONFIG_SERIAL_8250_SHARE_IRQ=y
> CONFIG_SERIAL_8250_DETECT_IRQ=y
> CONFIG_SERIAL_8250_RSA=y
> # CONFIG_SERIAL_8250_FSL is not set
> # CONFIG_SERIAL_8250_DW is not set
> # CONFIG_SERIAL_8250_RT288X is not set
> # CONFIG_SERIAL_8250_FINTEK is not set
> # CONFIG_SERIAL_8250_MID is not set
>
> #
> # Non-8250 serial port support
> #
> # CONFIG_SERIAL_UARTLITE is not set
> CONFIG_SERIAL_CORE=y
> CONFIG_SERIAL_CORE_CONSOLE=y
> # CONFIG_SERIAL_JSM is not set
> # CONFIG_SERIAL_SCCNXP is not set
> # CONFIG_SERIAL_SC16IS7XX is not set
> # CONFIG_SERIAL_ALTERA_JTAGUART is not set
> # CONFIG_SERIAL_ALTERA_UART is not set
> # CONFIG_SERIAL_ARC is not set
> # CONFIG_SERIAL_RP2 is not set
> # CONFIG_SERIAL_FSL_LPUART is not set
> # CONFIG_IPMI_HANDLER is not set
> CONFIG_HW_RANDOM=y
> # CONFIG_HW_RANDOM_TIMERIOMEM is not set
> # CONFIG_HW_RANDOM_INTEL is not set
> # CONFIG_HW_RANDOM_AMD is not set
> CONFIG_HW_RANDOM_VIA=y
> CONFIG_NVRAM=y
> # CONFIG_R3964 is not set
> # CONFIG_APPLICOM is not set
>
> #
> # PCMCIA character devices
> #
> # CONFIG_SYNCLINK_CS is not set
> # CONFIG_CARDMAN_4000 is not set
> # CONFIG_CARDMAN_4040 is not set
> # CONFIG_IPWIRELESS is not set
> # CONFIG_MWAVE is not set
> # CONFIG_RAW_DRIVER is not set
> CONFIG_HPET=y
> # CONFIG_HPET_MMAP is not set
> # CONFIG_HANGCHECK_TIMER is not set
> # CONFIG_TCG_TPM is not set
> # CONFIG_TELCLOCK is not set
> CONFIG_DEVPORT=y
> # CONFIG_XILLYBUS is not set
>
> #
> # I2C support
> #
> CONFIG_I2C=y
> CONFIG_ACPI_I2C_OPREGION=y
> CONFIG_I2C_BOARDINFO=y
> CONFIG_I2C_COMPAT=y
> # CONFIG_I2C_CHARDEV is not set
> # CONFIG_I2C_MUX is not set
> CONFIG_I2C_HELPER_AUTO=y
> CONFIG_I2C_ALGOBIT=y
>
> #
> # I2C Hardware Bus support
> #
>
> #
> # PC SMBus host controller drivers
> #
> # CONFIG_I2C_ALI1535 is not set
> # CONFIG_I2C_ALI1563 is not set
> # CONFIG_I2C_ALI15X3 is not set
> # CONFIG_I2C_AMD756 is not set
> # CONFIG_I2C_AMD8111 is not set
> CONFIG_I2C_I801=y
> # CONFIG_I2C_ISCH is not set
> # CONFIG_I2C_ISMT is not set
> # CONFIG_I2C_PIIX4 is not set
> # CONFIG_I2C_NFORCE2 is not set
> # CONFIG_I2C_SIS5595 is not set
> # CONFIG_I2C_SIS630 is not set
> # CONFIG_I2C_SIS96X is not set
> # CONFIG_I2C_VIA is not set
> # CONFIG_I2C_VIAPRO is not set
>
> #
> # ACPI drivers
> #
> # CONFIG_I2C_SCMI is not set
>
> #
> # I2C system bus drivers (mostly embedded / system-on-chip)
> #
> # CONFIG_I2C_DESIGNWARE_PCI is not set
> # CONFIG_I2C_OCORES is not set
> # CONFIG_I2C_PCA_PLATFORM is not set
> # CONFIG_I2C_PXA_PCI is not set
> # CONFIG_I2C_SIMTEC is not set
> # CONFIG_I2C_XILINX is not set
>
> #
> # External I2C/SMBus adapter drivers
> #
> # CONFIG_I2C_DIOLAN_U2C is not set
> # CONFIG_I2C_PARPORT_LIGHT is not set
> # CONFIG_I2C_ROBOTFUZZ_OSIF is not set
> # CONFIG_I2C_TAOS_EVM is not set
> # CONFIG_I2C_TINY_USB is not set
>
> #
> # Other I2C/SMBus bus drivers
> #
> # CONFIG_I2C_STUB is not set
> # CONFIG_I2C_SLAVE is not set
> # CONFIG_I2C_DEBUG_CORE is not set
> # CONFIG_I2C_DEBUG_ALGO is not set
> # CONFIG_I2C_DEBUG_BUS is not set
> # CONFIG_SPI is not set
> # CONFIG_SPMI is not set
> # CONFIG_HSI is not set
>
> #
> # PPS support
> #
> CONFIG_PPS=y
> # CONFIG_PPS_DEBUG is not set
>
> #
> # PPS clients support
> #
> # CONFIG_PPS_CLIENT_KTIMER is not set
> # CONFIG_PPS_CLIENT_LDISC is not set
> # CONFIG_PPS_CLIENT_GPIO is not set
>
> #
> # PPS generators support
> #
>
> #
> # PTP clock support
> #
> CONFIG_PTP_1588_CLOCK=y
>
> #
> # Enable PHYLIB and NETWORK_PHY_TIMESTAMPING to see the additional clocks.
> #
> CONFIG_ARCH_WANT_OPTIONAL_GPIOLIB=y
> # CONFIG_GPIOLIB is not set
> # CONFIG_W1 is not set
> CONFIG_POWER_SUPPLY=y
> # CONFIG_POWER_SUPPLY_DEBUG is not set
> # CONFIG_PDA_POWER is not set
> # CONFIG_TEST_POWER is not set
> # CONFIG_BATTERY_DS2780 is not set
> # CONFIG_BATTERY_DS2781 is not set
> # CONFIG_BATTERY_DS2782 is not set
> # CONFIG_BATTERY_SBS is not set
> # CONFIG_BATTERY_BQ27XXX is not set
> # CONFIG_BATTERY_MAX17040 is not set
> # CONFIG_BATTERY_MAX17042 is not set
> # CONFIG_CHARGER_MAX8903 is not set
> # CONFIG_CHARGER_LP8727 is not set
> # CONFIG_CHARGER_BQ2415X is not set
> # CONFIG_CHARGER_SMB347 is not set
> # CONFIG_BATTERY_GAUGE_LTC2941 is not set
> # CONFIG_POWER_RESET is not set
> # CONFIG_POWER_AVS is not set
> CONFIG_HWMON=y
> # CONFIG_HWMON_VID is not set
> # CONFIG_HWMON_DEBUG_CHIP is not set
>
> #
> # Native drivers
> #
> # CONFIG_SENSORS_ABITUGURU is not set
> # CONFIG_SENSORS_ABITUGURU3 is not set
> # CONFIG_SENSORS_AD7414 is not set
> # CONFIG_SENSORS_AD7418 is not set
> # CONFIG_SENSORS_ADM1021 is not set
> # CONFIG_SENSORS_ADM1025 is not set
> # CONFIG_SENSORS_ADM1026 is not set
> # CONFIG_SENSORS_ADM1029 is not set
> # CONFIG_SENSORS_ADM1031 is not set
> # CONFIG_SENSORS_ADM9240 is not set
> # CONFIG_SENSORS_ADT7410 is not set
> # CONFIG_SENSORS_ADT7411 is not set
> # CONFIG_SENSORS_ADT7462 is not set
> # CONFIG_SENSORS_ADT7470 is not set
> # CONFIG_SENSORS_ADT7475 is not set
> # CONFIG_SENSORS_ASC7621 is not set
> # CONFIG_SENSORS_K8TEMP is not set
> # CONFIG_SENSORS_K10TEMP is not set
> # CONFIG_SENSORS_FAM15H_POWER is not set
> # CONFIG_SENSORS_APPLESMC is not set
> # CONFIG_SENSORS_ASB100 is not set
> # CONFIG_SENSORS_ATXP1 is not set
> # CONFIG_SENSORS_DS620 is not set
> # CONFIG_SENSORS_DS1621 is not set
> # CONFIG_SENSORS_DELL_SMM is not set
> # CONFIG_SENSORS_I5K_AMB is not set
> # CONFIG_SENSORS_F71805F is not set
> # CONFIG_SENSORS_F71882FG is not set
> # CONFIG_SENSORS_F75375S is not set
> # CONFIG_SENSORS_FSCHMD is not set
> # CONFIG_SENSORS_GL518SM is not set
> # CONFIG_SENSORS_GL520SM is not set
> # CONFIG_SENSORS_G760A is not set
> # CONFIG_SENSORS_G762 is not set
> # CONFIG_SENSORS_HIH6130 is not set
> # CONFIG_SENSORS_I5500 is not set
> # CONFIG_SENSORS_CORETEMP is not set
> # CONFIG_SENSORS_IT87 is not set
> # CONFIG_SENSORS_JC42 is not set
> # CONFIG_SENSORS_POWR1220 is not set
> # CONFIG_SENSORS_LINEAGE is not set
> # CONFIG_SENSORS_LTC2945 is not set
> # CONFIG_SENSORS_LTC4151 is not set
> # CONFIG_SENSORS_LTC4215 is not set
> # CONFIG_SENSORS_LTC4222 is not set
> # CONFIG_SENSORS_LTC4245 is not set
> # CONFIG_SENSORS_LTC4260 is not set
> # CONFIG_SENSORS_LTC4261 is not set
> # CONFIG_SENSORS_MAX16065 is not set
> # CONFIG_SENSORS_MAX1619 is not set
> # CONFIG_SENSORS_MAX1668 is not set
> # CONFIG_SENSORS_MAX197 is not set
> # CONFIG_SENSORS_MAX6639 is not set
> # CONFIG_SENSORS_MAX6642 is not set
> # CONFIG_SENSORS_MAX6650 is not set
> # CONFIG_SENSORS_MAX6697 is not set
> # CONFIG_SENSORS_MAX31790 is not set
> # CONFIG_SENSORS_MCP3021 is not set
> # CONFIG_SENSORS_LM63 is not set
> # CONFIG_SENSORS_LM73 is not set
> # CONFIG_SENSORS_LM75 is not set
> # CONFIG_SENSORS_LM77 is not set
> # CONFIG_SENSORS_LM78 is not set
> # CONFIG_SENSORS_LM80 is not set
> # CONFIG_SENSORS_LM83 is not set
> # CONFIG_SENSORS_LM85 is not set
> # CONFIG_SENSORS_LM87 is not set
> # CONFIG_SENSORS_LM90 is not set
> # CONFIG_SENSORS_LM92 is not set
> # CONFIG_SENSORS_LM93 is not set
> # CONFIG_SENSORS_LM95234 is not set
> # CONFIG_SENSORS_LM95241 is not set
> # CONFIG_SENSORS_LM95245 is not set
> # CONFIG_SENSORS_PC87360 is not set
> # CONFIG_SENSORS_PC87427 is not set
> # CONFIG_SENSORS_NTC_THERMISTOR is not set
> # CONFIG_SENSORS_NCT6683 is not set
> # CONFIG_SENSORS_NCT6775 is not set
> # CONFIG_SENSORS_NCT7802 is not set
> # CONFIG_SENSORS_NCT7904 is not set
> # CONFIG_SENSORS_PCF8591 is not set
> # CONFIG_PMBUS is not set
> # CONFIG_SENSORS_SHT21 is not set
> # CONFIG_SENSORS_SHTC1 is not set
> # CONFIG_SENSORS_SIS5595 is not set
> # CONFIG_SENSORS_DME1737 is not set
> # CONFIG_SENSORS_EMC1403 is not set
> # CONFIG_SENSORS_EMC2103 is not set
> # CONFIG_SENSORS_EMC6W201 is not set
> # CONFIG_SENSORS_SMSC47M1 is not set
> # CONFIG_SENSORS_SMSC47M192 is not set
> # CONFIG_SENSORS_SMSC47B397 is not set
> # CONFIG_SENSORS_SCH56XX_COMMON is not set
> # CONFIG_SENSORS_SCH5627 is not set
> # CONFIG_SENSORS_SCH5636 is not set
> # CONFIG_SENSORS_SMM665 is not set
> # CONFIG_SENSORS_ADC128D818 is not set
> # CONFIG_SENSORS_ADS1015 is not set
> # CONFIG_SENSORS_ADS7828 is not set
> # CONFIG_SENSORS_AMC6821 is not set
> # CONFIG_SENSORS_INA209 is not set
> # CONFIG_SENSORS_INA2XX is not set
> # CONFIG_SENSORS_TC74 is not set
> # CONFIG_SENSORS_THMC50 is not set
> # CONFIG_SENSORS_TMP102 is not set
> # CONFIG_SENSORS_TMP103 is not set
> # CONFIG_SENSORS_TMP401 is not set
> # CONFIG_SENSORS_TMP421 is not set
> # CONFIG_SENSORS_VIA_CPUTEMP is not set
> # CONFIG_SENSORS_VIA686A is not set
> # CONFIG_SENSORS_VT1211 is not set
> # CONFIG_SENSORS_VT8231 is not set
> # CONFIG_SENSORS_W83781D is not set
> # CONFIG_SENSORS_W83791D is not set
> # CONFIG_SENSORS_W83792D is not set
> # CONFIG_SENSORS_W83793 is not set
> # CONFIG_SENSORS_W83795 is not set
> # CONFIG_SENSORS_W83L785TS is not set
> # CONFIG_SENSORS_W83L786NG is not set
> # CONFIG_SENSORS_W83627HF is not set
> # CONFIG_SENSORS_W83627EHF is not set
>
> #
> # ACPI drivers
> #
> # CONFIG_SENSORS_ACPI_POWER is not set
> # CONFIG_SENSORS_ATK0110 is not set
> CONFIG_THERMAL=y
> CONFIG_THERMAL_HWMON=y
> CONFIG_THERMAL_WRITABLE_TRIPS=y
> CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE=y
> # CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE is not set
> # CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE is not set
> # CONFIG_THERMAL_DEFAULT_GOV_POWER_ALLOCATOR is not set
> # CONFIG_THERMAL_GOV_FAIR_SHARE is not set
> CONFIG_THERMAL_GOV_STEP_WISE=y
> # CONFIG_THERMAL_GOV_BANG_BANG is not set
> CONFIG_THERMAL_GOV_USER_SPACE=y
> # CONFIG_THERMAL_GOV_POWER_ALLOCATOR is not set
> # CONFIG_THERMAL_EMULATION is not set
> # CONFIG_INTEL_POWERCLAMP is not set
> CONFIG_X86_PKG_TEMP_THERMAL=m
> # CONFIG_INTEL_SOC_DTS_THERMAL is not set
> # CONFIG_INT340X_THERMAL is not set
> # CONFIG_INTEL_PCH_THERMAL is not set
> CONFIG_WATCHDOG=y
> # CONFIG_WATCHDOG_CORE is not set
> # CONFIG_WATCHDOG_NOWAYOUT is not set
> # CONFIG_WATCHDOG_SYSFS is not set
>
> #
> # Watchdog Device Drivers
> #
> # CONFIG_SOFT_WATCHDOG is not set
> # CONFIG_XILINX_WATCHDOG is not set
> # CONFIG_ZIIRAVE_WATCHDOG is not set
> # CONFIG_CADENCE_WATCHDOG is not set
> # CONFIG_DW_WATCHDOG is not set
> # CONFIG_MAX63XX_WATCHDOG is not set
> # CONFIG_ACQUIRE_WDT is not set
> # CONFIG_ADVANTECH_WDT is not set
> # CONFIG_ALIM1535_WDT is not set
> # CONFIG_ALIM7101_WDT is not set
> # CONFIG_F71808E_WDT is not set
> # CONFIG_SP5100_TCO is not set
> # CONFIG_SBC_FITPC2_WATCHDOG is not set
> # CONFIG_EUROTECH_WDT is not set
> # CONFIG_IB700_WDT is not set
> # CONFIG_IBMASR is not set
> # CONFIG_WAFER_WDT is not set
> # CONFIG_I6300ESB_WDT is not set
> # CONFIG_IE6XX_WDT is not set
> # CONFIG_ITCO_WDT is not set
> # CONFIG_IT8712F_WDT is not set
> # CONFIG_IT87_WDT is not set
> # CONFIG_HP_WATCHDOG is not set
> # CONFIG_SC1200_WDT is not set
> # CONFIG_PC87413_WDT is not set
> # CONFIG_NV_TCO is not set
> # CONFIG_60XX_WDT is not set
> # CONFIG_CPU5_WDT is not set
> # CONFIG_SMSC_SCH311X_WDT is not set
> # CONFIG_SMSC37B787_WDT is not set
> # CONFIG_VIA_WDT is not set
> # CONFIG_W83627HF_WDT is not set
> # CONFIG_W83877F_WDT is not set
> # CONFIG_W83977F_WDT is not set
> # CONFIG_MACHZ_WDT is not set
> # CONFIG_SBC_EPX_C3_WATCHDOG is not set
> # CONFIG_BCM7038_WDT is not set
>
> #
> # PCI-based Watchdog Cards
> #
> # CONFIG_PCIPCWATCHDOG is not set
> # CONFIG_WDTPCI is not set
>
> #
> # USB-based Watchdog Cards
> #
> # CONFIG_USBPCWATCHDOG is not set
> CONFIG_SSB_POSSIBLE=y
>
> #
> # Sonics Silicon Backplane
> #
> # CONFIG_SSB is not set
> CONFIG_BCMA_POSSIBLE=y
>
> #
> # Broadcom specific AMBA
> #
> # CONFIG_BCMA is not set
>
> #
> # Multifunction device drivers
> #
> # CONFIG_MFD_CORE is not set
> # CONFIG_MFD_AS3711 is not set
> # CONFIG_PMIC_ADP5520 is not set
> # CONFIG_MFD_BCM590XX is not set
> # CONFIG_MFD_AXP20X is not set
> # CONFIG_MFD_CROS_EC is not set
> # CONFIG_PMIC_DA903X is not set
> # CONFIG_MFD_DA9052_I2C is not set
> # CONFIG_MFD_DA9055 is not set
> # CONFIG_MFD_DA9062 is not set
> # CONFIG_MFD_DA9063 is not set
> # CONFIG_MFD_DA9150 is not set
> # CONFIG_MFD_DLN2 is not set
> # CONFIG_MFD_MC13XXX_I2C is not set
> # CONFIG_HTC_PASIC3 is not set
> # CONFIG_LPC_ICH is not set
> # CONFIG_LPC_SCH is not set
> # CONFIG_MFD_INTEL_LPSS_ACPI is not set
> # CONFIG_MFD_INTEL_LPSS_PCI is not set
> # CONFIG_MFD_JANZ_CMODIO is not set
> # CONFIG_MFD_KEMPLD is not set
> # CONFIG_MFD_88PM800 is not set
> # CONFIG_MFD_88PM805 is not set
> # CONFIG_MFD_88PM860X is not set
> # CONFIG_MFD_MAX14577 is not set
> # CONFIG_MFD_MAX77693 is not set
> # CONFIG_MFD_MAX77843 is not set
> # CONFIG_MFD_MAX8907 is not set
> # CONFIG_MFD_MAX8925 is not set
> # CONFIG_MFD_MAX8997 is not set
> # CONFIG_MFD_MAX8998 is not set
> # CONFIG_MFD_MT6397 is not set
> # CONFIG_MFD_MENF21BMC is not set
> # CONFIG_MFD_VIPERBOARD is not set
> # CONFIG_MFD_RETU is not set
> # CONFIG_MFD_PCF50633 is not set
> # CONFIG_MFD_RDC321X is not set
> # CONFIG_MFD_RTSX_PCI is not set
> # CONFIG_MFD_RT5033 is not set
> # CONFIG_MFD_RTSX_USB is not set
> # CONFIG_MFD_RC5T583 is not set
> # CONFIG_MFD_RN5T618 is not set
> # CONFIG_MFD_SEC_CORE is not set
> # CONFIG_MFD_SI476X_CORE is not set
> # CONFIG_MFD_SM501 is not set
> # CONFIG_MFD_SKY81452 is not set
> # CONFIG_MFD_SMSC is not set
> # CONFIG_ABX500_CORE is not set
> # CONFIG_MFD_SYSCON is not set
> # CONFIG_MFD_TI_AM335X_TSCADC is not set
> # CONFIG_MFD_LP3943 is not set
> # CONFIG_MFD_LP8788 is not set
> # CONFIG_MFD_PALMAS is not set
> # CONFIG_TPS6105X is not set
> # CONFIG_TPS6507X is not set
> # CONFIG_MFD_TPS65090 is not set
> # CONFIG_MFD_TPS65217 is not set
> # CONFIG_MFD_TPS65218 is not set
> # CONFIG_MFD_TPS6586X is not set
> # CONFIG_MFD_TPS80031 is not set
> # CONFIG_TWL4030_CORE is not set
> # CONFIG_TWL6040_CORE is not set
> # CONFIG_MFD_WL1273_CORE is not set
> # CONFIG_MFD_LM3533 is not set
> # CONFIG_MFD_TMIO is not set
> # CONFIG_MFD_VX855 is not set
> # CONFIG_MFD_ARIZONA_I2C is not set
> # CONFIG_MFD_WM8400 is not set
> # CONFIG_MFD_WM831X_I2C is not set
> # CONFIG_MFD_WM8350_I2C is not set
> # CONFIG_MFD_WM8994 is not set
> # CONFIG_REGULATOR is not set
> # CONFIG_MEDIA_SUPPORT is not set
>
> #
> # Graphics support
> #
> CONFIG_AGP=y
> CONFIG_AGP_AMD64=y
> CONFIG_AGP_INTEL=y
> # CONFIG_AGP_SIS is not set
> # CONFIG_AGP_VIA is not set
> CONFIG_INTEL_GTT=y
> CONFIG_VGA_ARB=y
> CONFIG_VGA_ARB_MAX_GPUS=16
> # CONFIG_VGA_SWITCHEROO is not set
> CONFIG_DRM=y
> CONFIG_DRM_MIPI_DSI=y
> CONFIG_DRM_KMS_HELPER=y
> CONFIG_DRM_KMS_FB_HELPER=y
> CONFIG_DRM_FBDEV_EMULATION=y
> # CONFIG_DRM_LOAD_EDID_FIRMWARE is not set
>
> #
> # I2C encoder or helper chips
> #
> # CONFIG_DRM_I2C_ADV7511 is not set
> # CONFIG_DRM_I2C_CH7006 is not set
> # CONFIG_DRM_I2C_SIL164 is not set
> # CONFIG_DRM_I2C_NXP_TDA998X is not set
> # CONFIG_DRM_TDFX is not set
> # CONFIG_DRM_R128 is not set
> # CONFIG_DRM_RADEON is not set
> # CONFIG_DRM_AMDGPU is not set
> # CONFIG_DRM_NOUVEAU is not set
> CONFIG_DRM_I915=y
> # CONFIG_DRM_I915_PRELIMINARY_HW_SUPPORT is not set
> # CONFIG_DRM_MGA is not set
> # CONFIG_DRM_SIS is not set
> # CONFIG_DRM_VIA is not set
> # CONFIG_DRM_SAVAGE is not set
> # CONFIG_DRM_VGEM is not set
> # CONFIG_DRM_VMWGFX is not set
> # CONFIG_DRM_GMA500 is not set
> # CONFIG_DRM_UDL is not set
> # CONFIG_DRM_AST is not set
> # CONFIG_DRM_MGAG200 is not set
> # CONFIG_DRM_CIRRUS_QEMU is not set
> # CONFIG_DRM_QXL is not set
> # CONFIG_DRM_BOCHS is not set
> CONFIG_DRM_PANEL=y
>
> #
> # Display Panels
> #
> CONFIG_DRM_BRIDGE=y
>
> #
> # Display Interface Bridges
> #
>
> #
> # Frame buffer Devices
> #
> CONFIG_FB=y
> # CONFIG_FIRMWARE_EDID is not set
> CONFIG_FB_CMDLINE=y
> CONFIG_FB_NOTIFY=y
> # CONFIG_FB_DDC is not set
> # CONFIG_FB_BOOT_VESA_SUPPORT is not set
> CONFIG_FB_CFB_FILLRECT=y
> CONFIG_FB_CFB_COPYAREA=y
> CONFIG_FB_CFB_IMAGEBLIT=y
> # CONFIG_FB_CFB_REV_PIXELS_IN_BYTE is not set
> CONFIG_FB_SYS_FILLRECT=y
> CONFIG_FB_SYS_COPYAREA=y
> CONFIG_FB_SYS_IMAGEBLIT=y
> # CONFIG_FB_FOREIGN_ENDIAN is not set
> CONFIG_FB_SYS_FOPS=y
> # CONFIG_FB_SVGALIB is not set
> # CONFIG_FB_MACMODES is not set
> # CONFIG_FB_BACKLIGHT is not set
> CONFIG_FB_MODE_HELPERS=y
> CONFIG_FB_TILEBLITTING=y
>
> #
> # Frame buffer hardware drivers
> #
> # CONFIG_FB_CIRRUS is not set
> # CONFIG_FB_PM2 is not set
> # CONFIG_FB_CYBER2000 is not set
> # CONFIG_FB_ARC is not set
> # CONFIG_FB_ASILIANT is not set
> # CONFIG_FB_IMSTT is not set
> # CONFIG_FB_VGA16 is not set
> # CONFIG_FB_UVESA is not set
> # CONFIG_FB_VESA is not set
> CONFIG_FB_EFI=y
> # CONFIG_FB_N411 is not set
> # CONFIG_FB_HGA is not set
> # CONFIG_FB_OPENCORES is not set
> # CONFIG_FB_S1D13XXX is not set
> # CONFIG_FB_NVIDIA is not set
> # CONFIG_FB_RIVA is not set
> # CONFIG_FB_I740 is not set
> # CONFIG_FB_LE80578 is not set
> # CONFIG_FB_MATROX is not set
> # CONFIG_FB_RADEON is not set
> # CONFIG_FB_ATY128 is not set
> # CONFIG_FB_ATY is not set
> # CONFIG_FB_S3 is not set
> # CONFIG_FB_SAVAGE is not set
> # CONFIG_FB_SIS is not set
> # CONFIG_FB_NEOMAGIC is not set
> # CONFIG_FB_KYRO is not set
> # CONFIG_FB_3DFX is not set
> # CONFIG_FB_VOODOO1 is not set
> # CONFIG_FB_VT8623 is not set
> # CONFIG_FB_TRIDENT is not set
> # CONFIG_FB_ARK is not set
> # CONFIG_FB_PM3 is not set
> # CONFIG_FB_CARMINE is not set
> # CONFIG_FB_SMSCUFX is not set
> # CONFIG_FB_UDL is not set
> # CONFIG_FB_IBM_GXT4500 is not set
> # CONFIG_FB_VIRTUAL is not set
> # CONFIG_FB_METRONOME is not set
> # CONFIG_FB_MB862XX is not set
> # CONFIG_FB_BROADSHEET is not set
> # CONFIG_FB_AUO_K190X is not set
> # CONFIG_FB_SIMPLE is not set
> # CONFIG_FB_SM712 is not set
> CONFIG_BACKLIGHT_LCD_SUPPORT=y
> # CONFIG_LCD_CLASS_DEVICE is not set
> CONFIG_BACKLIGHT_CLASS_DEVICE=y
> CONFIG_BACKLIGHT_GENERIC=y
> # CONFIG_BACKLIGHT_APPLE is not set
> # CONFIG_BACKLIGHT_PM8941_WLED is not set
> # CONFIG_BACKLIGHT_SAHARA is not set
> # CONFIG_BACKLIGHT_ADP8860 is not set
> # CONFIG_BACKLIGHT_ADP8870 is not set
> # CONFIG_BACKLIGHT_LM3639 is not set
> # CONFIG_BACKLIGHT_LV5207LP is not set
> # CONFIG_BACKLIGHT_BD6107 is not set
> # CONFIG_VGASTATE is not set
> CONFIG_HDMI=y
>
> #
> # Console display driver support
> #
> CONFIG_VGA_CONSOLE=y
> CONFIG_VGACON_SOFT_SCROLLBACK=y
> CONFIG_VGACON_SOFT_SCROLLBACK_SIZE=64
> CONFIG_DUMMY_CONSOLE=y
> CONFIG_DUMMY_CONSOLE_COLUMNS=80
> CONFIG_DUMMY_CONSOLE_ROWS=25
> CONFIG_FRAMEBUFFER_CONSOLE=y
> CONFIG_FRAMEBUFFER_CONSOLE_DETECT_PRIMARY=y
> # CONFIG_FRAMEBUFFER_CONSOLE_ROTATION is not set
> CONFIG_LOGO=y
> # CONFIG_LOGO_LINUX_MONO is not set
> # CONFIG_LOGO_LINUX_VGA16 is not set
> CONFIG_LOGO_LINUX_CLUT224=y
> CONFIG_SOUND=y
> CONFIG_SOUND_OSS_CORE=y
> CONFIG_SOUND_OSS_CORE_PRECLAIM=y
> CONFIG_SND=y
> CONFIG_SND_TIMER=y
> CONFIG_SND_PCM=y
> CONFIG_SND_HWDEP=y
> CONFIG_SND_JACK=y
> CONFIG_SND_SEQUENCER=y
> CONFIG_SND_SEQ_DUMMY=y
> CONFIG_SND_OSSEMUL=y
> CONFIG_SND_MIXER_OSS=y
> CONFIG_SND_PCM_OSS=y
> CONFIG_SND_PCM_OSS_PLUGINS=y
> CONFIG_SND_PCM_TIMER=y
> CONFIG_SND_SEQUENCER_OSS=y
> CONFIG_SND_HRTIMER=y
> CONFIG_SND_SEQ_HRTIMER_DEFAULT=y
> # CONFIG_SND_DYNAMIC_MINORS is not set
> CONFIG_SND_SUPPORT_OLD_API=y
> CONFIG_SND_PROC_FS=y
> CONFIG_SND_VERBOSE_PROCFS=y
> # CONFIG_SND_VERBOSE_PRINTK is not set
> # CONFIG_SND_DEBUG is not set
> CONFIG_SND_VMASTER=y
> CONFIG_SND_DMA_SGBUF=y
> # CONFIG_SND_RAWMIDI_SEQ is not set
> # CONFIG_SND_OPL3_LIB_SEQ is not set
> # CONFIG_SND_OPL4_LIB_SEQ is not set
> # CONFIG_SND_SBAWE_SEQ is not set
> # CONFIG_SND_EMU10K1_SEQ is not set
> CONFIG_SND_DRIVERS=y
> # CONFIG_SND_PCSP is not set
> # CONFIG_SND_DUMMY is not set
> # CONFIG_SND_ALOOP is not set
> # CONFIG_SND_VIRMIDI is not set
> # CONFIG_SND_MTPAV is not set
> # CONFIG_SND_SERIAL_U16550 is not set
> # CONFIG_SND_MPU401 is not set
> CONFIG_SND_PCI=y
> # CONFIG_SND_AD1889 is not set
> # CONFIG_SND_ALS300 is not set
> # CONFIG_SND_ALS4000 is not set
> # CONFIG_SND_ALI5451 is not set
> # CONFIG_SND_ASIHPI is not set
> # CONFIG_SND_ATIIXP is not set
> # CONFIG_SND_ATIIXP_MODEM is not set
> # CONFIG_SND_AU8810 is not set
> # CONFIG_SND_AU8820 is not set
> # CONFIG_SND_AU8830 is not set
> # CONFIG_SND_AW2 is not set
> # CONFIG_SND_AZT3328 is not set
> # CONFIG_SND_BT87X is not set
> # CONFIG_SND_CA0106 is not set
> # CONFIG_SND_CMIPCI is not set
> # CONFIG_SND_OXYGEN is not set
> # CONFIG_SND_CS4281 is not set
> # CONFIG_SND_CS46XX is not set
> # CONFIG_SND_CTXFI is not set
> # CONFIG_SND_DARLA20 is not set
> # CONFIG_SND_GINA20 is not set
> # CONFIG_SND_LAYLA20 is not set
> # CONFIG_SND_DARLA24 is not set
> # CONFIG_SND_GINA24 is not set
> # CONFIG_SND_LAYLA24 is not set
> # CONFIG_SND_MONA is not set
> # CONFIG_SND_MIA is not set
> # CONFIG_SND_ECHO3G is not set
> # CONFIG_SND_INDIGO is not set
> # CONFIG_SND_INDIGOIO is not set
> # CONFIG_SND_INDIGODJ is not set
> # CONFIG_SND_INDIGOIOX is not set
> # CONFIG_SND_INDIGODJX is not set
> # CONFIG_SND_EMU10K1 is not set
> # CONFIG_SND_EMU10K1X is not set
> # CONFIG_SND_ENS1370 is not set
> # CONFIG_SND_ENS1371 is not set
> # CONFIG_SND_ES1938 is not set
> # CONFIG_SND_ES1968 is not set
> # CONFIG_SND_FM801 is not set
> # CONFIG_SND_HDSP is not set
> # CONFIG_SND_HDSPM is not set
> # CONFIG_SND_ICE1712 is not set
> # CONFIG_SND_ICE1724 is not set
> # CONFIG_SND_INTEL8X0 is not set
> # CONFIG_SND_INTEL8X0M is not set
> # CONFIG_SND_KORG1212 is not set
> # CONFIG_SND_LOLA is not set
> # CONFIG_SND_LX6464ES is not set
> # CONFIG_SND_MAESTRO3 is not set
> # CONFIG_SND_MIXART is not set
> # CONFIG_SND_NM256 is not set
> # CONFIG_SND_PCXHR is not set
> # CONFIG_SND_RIPTIDE is not set
> # CONFIG_SND_RME32 is not set
> # CONFIG_SND_RME96 is not set
> # CONFIG_SND_RME9652 is not set
> # CONFIG_SND_SE6X is not set
> # CONFIG_SND_SONICVIBES is not set
> # CONFIG_SND_TRIDENT is not set
> # CONFIG_SND_VIA82XX is not set
> # CONFIG_SND_VIA82XX_MODEM is not set
> # CONFIG_SND_VIRTUOSO is not set
> # CONFIG_SND_VX222 is not set
> # CONFIG_SND_YMFPCI is not set
>
> #
> # HD-Audio
> #
> CONFIG_SND_HDA=y
> CONFIG_SND_HDA_INTEL=y
> CONFIG_SND_HDA_HWDEP=y
> # CONFIG_SND_HDA_RECONFIG is not set
> # CONFIG_SND_HDA_INPUT_BEEP is not set
> # CONFIG_SND_HDA_PATCH_LOADER is not set
> # CONFIG_SND_HDA_CODEC_REALTEK is not set
> # CONFIG_SND_HDA_CODEC_ANALOG is not set
> # CONFIG_SND_HDA_CODEC_SIGMATEL is not set
> # CONFIG_SND_HDA_CODEC_VIA is not set
> # CONFIG_SND_HDA_CODEC_HDMI is not set
> # CONFIG_SND_HDA_CODEC_CIRRUS is not set
> # CONFIG_SND_HDA_CODEC_CONEXANT is not set
> # CONFIG_SND_HDA_CODEC_CA0110 is not set
> # CONFIG_SND_HDA_CODEC_CA0132 is not set
> # CONFIG_SND_HDA_CODEC_CMEDIA is not set
> # CONFIG_SND_HDA_CODEC_SI3054 is not set
> # CONFIG_SND_HDA_GENERIC is not set
> CONFIG_SND_HDA_POWER_SAVE_DEFAULT=0
> CONFIG_SND_HDA_CORE=y
> CONFIG_SND_HDA_I915=y
> CONFIG_SND_HDA_PREALLOC_SIZE=64
> CONFIG_SND_USB=y
> # CONFIG_SND_USB_AUDIO is not set
> # CONFIG_SND_USB_UA101 is not set
> # CONFIG_SND_USB_USX2Y is not set
> # CONFIG_SND_USB_CAIAQ is not set
> # CONFIG_SND_USB_US122L is not set
> # CONFIG_SND_USB_6FIRE is not set
> # CONFIG_SND_USB_HIFACE is not set
> # CONFIG_SND_BCD2000 is not set
> # CONFIG_SND_USB_POD is not set
> # CONFIG_SND_USB_PODHD is not set
> # CONFIG_SND_USB_TONEPORT is not set
> # CONFIG_SND_USB_VARIAX is not set
> CONFIG_SND_PCMCIA=y
> # CONFIG_SND_VXPOCKET is not set
> # CONFIG_SND_PDAUDIOCF is not set
> # CONFIG_SND_SOC is not set
> # CONFIG_SOUND_PRIME is not set
>
> #
> # HID support
> #
> CONFIG_HID=y
> # CONFIG_HID_BATTERY_STRENGTH is not set
> CONFIG_HIDRAW=y
> # CONFIG_UHID is not set
> CONFIG_HID_GENERIC=y
>
> #
> # Special HID drivers
> #
> CONFIG_HID_A4TECH=y
> # CONFIG_HID_ACRUX is not set
> CONFIG_HID_APPLE=y
> # CONFIG_HID_APPLEIR is not set
> # CONFIG_HID_AUREAL is not set
> CONFIG_HID_BELKIN=y
> # CONFIG_HID_BETOP_FF is not set
> CONFIG_HID_CHERRY=y
> CONFIG_HID_CHICONY=y
> # CONFIG_HID_CORSAIR is not set
> # CONFIG_HID_PRODIKEYS is not set
> CONFIG_HID_CYPRESS=y
> # CONFIG_HID_DRAGONRISE is not set
> # CONFIG_HID_EMS_FF is not set
> # CONFIG_HID_ELECOM is not set
> # CONFIG_HID_ELO is not set
> CONFIG_HID_EZKEY=y
> # CONFIG_HID_GEMBIRD is not set
> # CONFIG_HID_GFRM is not set
> # CONFIG_HID_HOLTEK is not set
> # CONFIG_HID_GT683R is not set
> # CONFIG_HID_KEYTOUCH is not set
> # CONFIG_HID_KYE is not set
> # CONFIG_HID_UCLOGIC is not set
> # CONFIG_HID_WALTOP is not set
> CONFIG_HID_GYRATION=y
> # CONFIG_HID_ICADE is not set
> # CONFIG_HID_TWINHAN is not set
> CONFIG_HID_KENSINGTON=y
> # CONFIG_HID_LCPOWER is not set
> # CONFIG_HID_LENOVO is not set
> CONFIG_HID_LOGITECH=y
> # CONFIG_HID_LOGITECH_DJ is not set
> # CONFIG_HID_LOGITECH_HIDPP is not set
> CONFIG_LOGITECH_FF=y
> # CONFIG_LOGIRUMBLEPAD2_FF is not set
> # CONFIG_LOGIG940_FF is not set
> CONFIG_LOGIWHEELS_FF=y
> # CONFIG_HID_MAGICMOUSE is not set
> CONFIG_HID_MICROSOFT=y
> CONFIG_HID_MONTEREY=y
> # CONFIG_HID_MULTITOUCH is not set
> CONFIG_HID_NTRIG=y
> # CONFIG_HID_ORTEK is not set
> CONFIG_HID_PANTHERLORD=y
> CONFIG_PANTHERLORD_FF=y
> # CONFIG_HID_PENMOUNT is not set
> CONFIG_HID_PETALYNX=y
> # CONFIG_HID_PICOLCD is not set
> # CONFIG_HID_PLANTRONICS is not set
> # CONFIG_HID_PRIMAX is not set
> # CONFIG_HID_ROCCAT is not set
> # CONFIG_HID_SAITEK is not set
> CONFIG_HID_SAMSUNG=y
> CONFIG_HID_SONY=y
> # CONFIG_SONY_FF is not set
> # CONFIG_HID_SPEEDLINK is not set
> # CONFIG_HID_STEELSERIES is not set
> CONFIG_HID_SUNPLUS=y
> # CONFIG_HID_RMI is not set
> # CONFIG_HID_GREENASIA is not set
> # CONFIG_HID_SMARTJOYPLUS is not set
> # CONFIG_HID_TIVO is not set
> CONFIG_HID_TOPSEED=y
> # CONFIG_HID_THINGM is not set
> # CONFIG_HID_THRUSTMASTER is not set
> # CONFIG_HID_WACOM is not set
> # CONFIG_HID_WIIMOTE is not set
> # CONFIG_HID_XINMO is not set
> # CONFIG_HID_ZEROPLUS is not set
> # CONFIG_HID_ZYDACRON is not set
> # CONFIG_HID_SENSOR_HUB is not set
>
> #
> # USB HID support
> #
> CONFIG_USB_HID=y
> CONFIG_HID_PID=y
> CONFIG_USB_HIDDEV=y
>
> #
> # I2C HID support
> #
> # CONFIG_I2C_HID is not set
> CONFIG_USB_OHCI_LITTLE_ENDIAN=y
> CONFIG_USB_SUPPORT=y
> CONFIG_USB_COMMON=y
> CONFIG_USB_ARCH_HAS_HCD=y
> CONFIG_USB=y
> CONFIG_USB_ANNOUNCE_NEW_DEVICES=y
>
> #
> # Miscellaneous USB options
> #
> CONFIG_USB_DEFAULT_PERSIST=y
> # CONFIG_USB_DYNAMIC_MINORS is not set
> # CONFIG_USB_OTG is not set
> # CONFIG_USB_OTG_WHITELIST is not set
> # CONFIG_USB_ULPI_BUS is not set
> CONFIG_USB_MON=y
> # CONFIG_USB_WUSB_CBAF is not set
>
> #
> # USB Host Controller Drivers
> #
> # CONFIG_USB_C67X00_HCD is not set
> # CONFIG_USB_XHCI_HCD is not set
> CONFIG_USB_EHCI_HCD=y
> # CONFIG_USB_EHCI_ROOT_HUB_TT is not set
> CONFIG_USB_EHCI_TT_NEWSCHED=y
> CONFIG_USB_EHCI_PCI=y
> # CONFIG_USB_EHCI_HCD_PLATFORM is not set
> # CONFIG_USB_OXU210HP_HCD is not set
> # CONFIG_USB_ISP116X_HCD is not set
> # CONFIG_USB_ISP1362_HCD is not set
> # CONFIG_USB_FOTG210_HCD is not set
> CONFIG_USB_OHCI_HCD=y
> CONFIG_USB_OHCI_HCD_PCI=y
> # CONFIG_USB_OHCI_HCD_PLATFORM is not set
> CONFIG_USB_UHCI_HCD=y
> # CONFIG_USB_SL811_HCD is not set
> # CONFIG_USB_R8A66597_HCD is not set
> # CONFIG_USB_HCD_TEST_MODE is not set
>
> #
> # USB Device Class drivers
> #
> # CONFIG_USB_ACM is not set
> CONFIG_USB_PRINTER=y
> # CONFIG_USB_WDM is not set
> # CONFIG_USB_TMC is not set
>
> #
> # NOTE: USB_STORAGE depends on SCSI but BLK_DEV_SD may
> #
>
> #
> # also be needed; see USB_STORAGE Help for more info
> #
> CONFIG_USB_STORAGE=y
> # CONFIG_USB_STORAGE_DEBUG is not set
> # CONFIG_USB_STORAGE_REALTEK is not set
> # CONFIG_USB_STORAGE_DATAFAB is not set
> # CONFIG_USB_STORAGE_FREECOM is not set
> # CONFIG_USB_STORAGE_ISD200 is not set
> # CONFIG_USB_STORAGE_USBAT is not set
> # CONFIG_USB_STORAGE_SDDR09 is not set
> # CONFIG_USB_STORAGE_SDDR55 is not set
> # CONFIG_USB_STORAGE_JUMPSHOT is not set
> # CONFIG_USB_STORAGE_ALAUDA is not set
> # CONFIG_USB_STORAGE_ONETOUCH is not set
> # CONFIG_USB_STORAGE_KARMA is not set
> # CONFIG_USB_STORAGE_CYPRESS_ATACB is not set
> # CONFIG_USB_STORAGE_ENE_UB6250 is not set
> # CONFIG_USB_UAS is not set
>
> #
> # USB Imaging devices
> #
> # CONFIG_USB_MDC800 is not set
> # CONFIG_USB_MICROTEK is not set
> # CONFIG_USBIP_CORE is not set
> # CONFIG_USB_MUSB_HDRC is not set
> # CONFIG_USB_DWC3 is not set
> # CONFIG_USB_DWC2 is not set
> # CONFIG_USB_CHIPIDEA is not set
> # CONFIG_USB_ISP1760 is not set
>
> #
> # USB port drivers
> #
> # CONFIG_USB_SERIAL is not set
>
> #
> # USB Miscellaneous drivers
> #
> # CONFIG_USB_EMI62 is not set
> # CONFIG_USB_EMI26 is not set
> # CONFIG_USB_ADUTUX is not set
> # CONFIG_USB_SEVSEG is not set
> # CONFIG_USB_RIO500 is not set
> # CONFIG_USB_LEGOTOWER is not set
> # CONFIG_USB_LCD is not set
> # CONFIG_USB_LED is not set
> # CONFIG_USB_CYPRESS_CY7C63 is not set
> # CONFIG_USB_CYTHERM is not set
> # CONFIG_USB_IDMOUSE is not set
> # CONFIG_USB_FTDI_ELAN is not set
> # CONFIG_USB_APPLEDISPLAY is not set
> # CONFIG_USB_SISUSBVGA is not set
> # CONFIG_USB_LD is not set
> # CONFIG_USB_TRANCEVIBRATOR is not set
> # CONFIG_USB_IOWARRIOR is not set
> # CONFIG_USB_TEST is not set
> # CONFIG_USB_EHSET_TEST_FIXTURE is not set
> # CONFIG_USB_ISIGHTFW is not set
> # CONFIG_USB_YUREX is not set
> # CONFIG_USB_EZUSB_FX2 is not set
> # CONFIG_USB_HSIC_USB3503 is not set
> # CONFIG_USB_LINK_LAYER_TEST is not set
> # CONFIG_USB_CHAOSKEY is not set
>
> #
> # USB Physical Layer drivers
> #
> # CONFIG_USB_PHY is not set
> # CONFIG_NOP_USB_XCEIV is not set
> # CONFIG_USB_ISP1301 is not set
> # CONFIG_USB_GADGET is not set
> # CONFIG_USB_LED_TRIG is not set
> # CONFIG_UWB is not set
> # CONFIG_MMC is not set
> # CONFIG_MEMSTICK is not set
> CONFIG_NEW_LEDS=y
> CONFIG_LEDS_CLASS=y
> # CONFIG_LEDS_CLASS_FLASH is not set
>
> #
> # LED drivers
> #
> # CONFIG_LEDS_LM3530 is not set
> # CONFIG_LEDS_LM3642 is not set
> # CONFIG_LEDS_PCA9532 is not set
> # CONFIG_LEDS_LP3944 is not set
> # CONFIG_LEDS_LP5521 is not set
> # CONFIG_LEDS_LP5523 is not set
> # CONFIG_LEDS_LP5562 is not set
> # CONFIG_LEDS_LP8501 is not set
> # CONFIG_LEDS_LP8860 is not set
> # CONFIG_LEDS_CLEVO_MAIL is not set
> # CONFIG_LEDS_PCA955X is not set
> # CONFIG_LEDS_PCA963X is not set
> # CONFIG_LEDS_BD2802 is not set
> # CONFIG_LEDS_INTEL_SS4200 is not set
> # CONFIG_LEDS_TCA6507 is not set
> # CONFIG_LEDS_TLC591XX is not set
> # CONFIG_LEDS_LM355x is not set
>
> #
> # LED driver for blink(1) USB RGB LED is under Special HID drivers (HID_THINGM)
> #
> # CONFIG_LEDS_BLINKM is not set
>
> #
> # LED Triggers
> #
> CONFIG_LEDS_TRIGGERS=y
> # CONFIG_LEDS_TRIGGER_TIMER is not set
> # CONFIG_LEDS_TRIGGER_ONESHOT is not set
> # CONFIG_LEDS_TRIGGER_HEARTBEAT is not set
> # CONFIG_LEDS_TRIGGER_BACKLIGHT is not set
> # CONFIG_LEDS_TRIGGER_CPU is not set
> # CONFIG_LEDS_TRIGGER_DEFAULT_ON is not set
>
> #
> # iptables trigger is under Netfilter config (LED target)
> #
> # CONFIG_LEDS_TRIGGER_TRANSIENT is not set
> # CONFIG_LEDS_TRIGGER_CAMERA is not set
> # CONFIG_ACCESSIBILITY is not set
> # CONFIG_INFINIBAND is not set
> CONFIG_EDAC_ATOMIC_SCRUB=y
> CONFIG_EDAC_SUPPORT=y
> CONFIG_EDAC=y
> CONFIG_EDAC_LEGACY_SYSFS=y
> # CONFIG_EDAC_DEBUG is not set
> CONFIG_EDAC_DECODE_MCE=y
> # CONFIG_EDAC_MM_EDAC is not set
> CONFIG_RTC_LIB=y
> CONFIG_RTC_CLASS=y
> # CONFIG_RTC_HCTOSYS is not set
> CONFIG_RTC_SYSTOHC=y
> CONFIG_RTC_SYSTOHC_DEVICE="rtc0"
> # CONFIG_RTC_DEBUG is not set
>
> #
> # RTC interfaces
> #
> CONFIG_RTC_INTF_SYSFS=y
> CONFIG_RTC_INTF_PROC=y
> CONFIG_RTC_INTF_DEV=y
> # CONFIG_RTC_INTF_DEV_UIE_EMUL is not set
> # CONFIG_RTC_DRV_TEST is not set
>
> #
> # I2C RTC drivers
> #
> # CONFIG_RTC_DRV_ABB5ZES3 is not set
> # CONFIG_RTC_DRV_ABX80X is not set
> # CONFIG_RTC_DRV_DS1307 is not set
> # CONFIG_RTC_DRV_DS1374 is not set
> # CONFIG_RTC_DRV_DS1672 is not set
> # CONFIG_RTC_DRV_DS3232 is not set
> # CONFIG_RTC_DRV_MAX6900 is not set
> # CONFIG_RTC_DRV_RS5C372 is not set
> # CONFIG_RTC_DRV_ISL1208 is not set
> # CONFIG_RTC_DRV_ISL12022 is not set
> # CONFIG_RTC_DRV_ISL12057 is not set
> # CONFIG_RTC_DRV_X1205 is not set
> # CONFIG_RTC_DRV_PCF2127 is not set
> # CONFIG_RTC_DRV_PCF8523 is not set
> # CONFIG_RTC_DRV_PCF8563 is not set
> # CONFIG_RTC_DRV_PCF85063 is not set
> # CONFIG_RTC_DRV_PCF8583 is not set
> # CONFIG_RTC_DRV_M41T80 is not set
> # CONFIG_RTC_DRV_BQ32K is not set
> # CONFIG_RTC_DRV_S35390A is not set
> # CONFIG_RTC_DRV_FM3130 is not set
> # CONFIG_RTC_DRV_RX8010 is not set
> # CONFIG_RTC_DRV_RX8581 is not set
> # CONFIG_RTC_DRV_RX8025 is not set
> # CONFIG_RTC_DRV_EM3027 is not set
> # CONFIG_RTC_DRV_RV3029C2 is not set
> # CONFIG_RTC_DRV_RV8803 is not set
>
> #
> # SPI RTC drivers
> #
>
> #
> # Platform RTC drivers
> #
> CONFIG_RTC_DRV_CMOS=y
> # CONFIG_RTC_DRV_DS1286 is not set
> # CONFIG_RTC_DRV_DS1511 is not set
> # CONFIG_RTC_DRV_DS1553 is not set
> # CONFIG_RTC_DRV_DS1685_FAMILY is not set
> # CONFIG_RTC_DRV_DS1742 is not set
> # CONFIG_RTC_DRV_DS2404 is not set
> # CONFIG_RTC_DRV_STK17TA8 is not set
> # CONFIG_RTC_DRV_M48T86 is not set
> # CONFIG_RTC_DRV_M48T35 is not set
> # CONFIG_RTC_DRV_M48T59 is not set
> # CONFIG_RTC_DRV_MSM6242 is not set
> # CONFIG_RTC_DRV_BQ4802 is not set
> # CONFIG_RTC_DRV_RP5C01 is not set
> # CONFIG_RTC_DRV_V3020 is not set
>
> #
> # on-CPU RTC drivers
> #
>
> #
> # HID Sensor RTC drivers
> #
> # CONFIG_RTC_DRV_HID_SENSOR_TIME is not set
> CONFIG_DMADEVICES=y
> # CONFIG_DMADEVICES_DEBUG is not set
>
> #
> # DMA Devices
> #
> CONFIG_DMA_ACPI=y
> # CONFIG_INTEL_IDMA64 is not set
> # CONFIG_INTEL_IOATDMA is not set
> # CONFIG_DW_DMAC is not set
> # CONFIG_DW_DMAC_PCI is not set
> # CONFIG_AUXDISPLAY is not set
> # CONFIG_UIO is not set
> # CONFIG_VFIO is not set
> # CONFIG_VIRT_DRIVERS is not set
>
> #
> # Virtio drivers
> #
> # CONFIG_VIRTIO_PCI is not set
> # CONFIG_VIRTIO_MMIO is not set
>
> #
> # Microsoft Hyper-V guest support
> #
> # CONFIG_STAGING is not set
> CONFIG_X86_PLATFORM_DEVICES=y
> # CONFIG_ACERHDF is not set
> # CONFIG_ASUS_LAPTOP is not set
> # CONFIG_DELL_SMO8800 is not set
> # CONFIG_DELL_RBTN is not set
> # CONFIG_FUJITSU_LAPTOP is not set
> # CONFIG_FUJITSU_TABLET is not set
> # CONFIG_AMILO_RFKILL is not set
> # CONFIG_HP_ACCEL is not set
> # CONFIG_HP_WIRELESS is not set
> # CONFIG_MSI_LAPTOP is not set
> # CONFIG_PANASONIC_LAPTOP is not set
> # CONFIG_COMPAL_LAPTOP is not set
> # CONFIG_SONY_LAPTOP is not set
> # CONFIG_IDEAPAD_LAPTOP is not set
> # CONFIG_THINKPAD_ACPI is not set
> # CONFIG_SENSORS_HDAPS is not set
> # CONFIG_INTEL_MENLOW is not set
> CONFIG_EEEPC_LAPTOP=y
> # CONFIG_ASUS_WIRELESS is not set
> # CONFIG_ACPI_WMI is not set
> # CONFIG_TOPSTAR_LAPTOP is not set
> # CONFIG_TOSHIBA_BT_RFKILL is not set
> # CONFIG_TOSHIBA_HAPS is not set
> # CONFIG_ACPI_CMPC is not set
> # CONFIG_INTEL_HID_EVENT is not set
> # CONFIG_INTEL_IPS is not set
> # CONFIG_IBM_RTL is not set
> # CONFIG_SAMSUNG_LAPTOP is not set
> # CONFIG_INTEL_OAKTRAIL is not set
> # CONFIG_SAMSUNG_Q10 is not set
> # CONFIG_APPLE_GMUX is not set
> # CONFIG_INTEL_RST is not set
> # CONFIG_INTEL_SMARTCONNECT is not set
> # CONFIG_PVPANIC is not set
> # CONFIG_INTEL_PMC_IPC is not set
> # CONFIG_SURFACE_PRO3_BUTTON is not set
> # CONFIG_INTEL_PUNIT_IPC is not set
> # CONFIG_CHROME_PLATFORMS is not set
>
> #
> # Hardware Spinlock drivers
> #
>
> #
> # Clock Source drivers
> #
> CONFIG_CLKEVT_I8253=y
> CONFIG_I8253_LOCK=y
> CONFIG_CLKBLD_I8253=y
> # CONFIG_ATMEL_PIT is not set
> # CONFIG_SH_TIMER_CMT is not set
> # CONFIG_SH_TIMER_MTU2 is not set
> # CONFIG_SH_TIMER_TMU is not set
> # CONFIG_EM_TIMER_STI is not set
> # CONFIG_MAILBOX is not set
> CONFIG_IOMMU_API=y
> CONFIG_IOMMU_SUPPORT=y
>
> #
> # Generic IOMMU Pagetable Support
> #
> CONFIG_IOMMU_IOVA=y
> CONFIG_AMD_IOMMU=y
> CONFIG_AMD_IOMMU_STATS=y
> # CONFIG_AMD_IOMMU_V2 is not set
> CONFIG_DMAR_TABLE=y
> CONFIG_INTEL_IOMMU=y
> # CONFIG_INTEL_IOMMU_SVM is not set
> # CONFIG_INTEL_IOMMU_DEFAULT_ON is not set
> CONFIG_INTEL_IOMMU_FLOPPY_WA=y
> # CONFIG_IRQ_REMAP is not set
>
> #
> # Remoteproc drivers
> #
> # CONFIG_STE_MODEM_RPROC is not set
>
> #
> # Rpmsg drivers
> #
>
> #
> # SOC (System On Chip) specific Drivers
> #
> # CONFIG_SUNXI_SRAM is not set
> # CONFIG_SOC_TI is not set
> # CONFIG_PM_DEVFREQ is not set
> # CONFIG_EXTCON is not set
> # CONFIG_MEMORY is not set
> # CONFIG_IIO is not set
> # CONFIG_NTB is not set
> # CONFIG_VME_BUS is not set
> # CONFIG_PWM is not set
> CONFIG_ARM_GIC_MAX_NR=1
> # CONFIG_TS4800_IRQ is not set
> # CONFIG_IPACK_BUS is not set
> # CONFIG_RESET_CONTROLLER is not set
> # CONFIG_FMC is not set
>
> #
> # PHY Subsystem
> #
> # CONFIG_GENERIC_PHY is not set
> # CONFIG_PHY_PXA_28NM_HSIC is not set
> # CONFIG_PHY_PXA_28NM_USB2 is not set
> # CONFIG_BCM_KONA_USB2_PHY is not set
> # CONFIG_PHY_HI6220_USB is not set
> # CONFIG_POWERCAP is not set
> # CONFIG_MCB is not set
>
> #
> # Performance monitor support
> #
> CONFIG_RAS=y
> # CONFIG_AMD_MCE_INJ is not set
> # CONFIG_THUNDERBOLT is not set
>
> #
> # Android
> #
> # CONFIG_ANDROID is not set
> # CONFIG_LIBNVDIMM is not set
> # CONFIG_NVMEM is not set
> # CONFIG_STM is not set
> # CONFIG_STM_DUMMY is not set
> # CONFIG_STM_SOURCE_CONSOLE is not set
> # CONFIG_INTEL_TH is not set
>
> #
> # FPGA Configuration Support
> #
> # CONFIG_FPGA is not set
>
> #
> # Firmware Drivers
> #
> # CONFIG_EDD is not set
> CONFIG_FIRMWARE_MEMMAP=y
> # CONFIG_DELL_RBU is not set
> # CONFIG_DCDBAS is not set
> CONFIG_DMIID=y
> # CONFIG_DMI_SYSFS is not set
> CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK=y
> # CONFIG_ISCSI_IBFT_FIND is not set
> # CONFIG_GOOGLE_FIRMWARE is not set
>
> #
> # EFI (Extensible Firmware Interface) Support
> #
> CONFIG_EFI_VARS=y
> CONFIG_EFI_ESRT=y
> CONFIG_EFI_RUNTIME_MAP=y
> # CONFIG_EFI_FAKE_MEMMAP is not set
> CONFIG_EFI_RUNTIME_WRAPPERS=y
>
> #
> # File systems
> #
> CONFIG_DCACHE_WORD_ACCESS=y
> # CONFIG_EXT2_FS is not set
> # CONFIG_EXT3_FS is not set
> CONFIG_EXT4_FS=y
> CONFIG_EXT4_USE_FOR_EXT2=y
> CONFIG_EXT4_FS_POSIX_ACL=y
> CONFIG_EXT4_FS_SECURITY=y
> # CONFIG_EXT4_ENCRYPTION is not set
> # CONFIG_EXT4_DEBUG is not set
> CONFIG_JBD2=y
> # CONFIG_JBD2_DEBUG is not set
> CONFIG_FS_MBCACHE=y
> # CONFIG_REISERFS_FS is not set
> # CONFIG_JFS_FS is not set
> # CONFIG_XFS_FS is not set
> # CONFIG_GFS2_FS is not set
> # CONFIG_BTRFS_FS is not set
> # CONFIG_NILFS2_FS is not set
> # CONFIG_F2FS_FS is not set
> # CONFIG_FS_DAX is not set
> CONFIG_FS_POSIX_ACL=y
> CONFIG_EXPORTFS=y
> CONFIG_FILE_LOCKING=y
> CONFIG_MANDATORY_FILE_LOCKING=y
> CONFIG_FSNOTIFY=y
> CONFIG_DNOTIFY=y
> CONFIG_INOTIFY_USER=y
> # CONFIG_FANOTIFY is not set
> CONFIG_QUOTA=y
> CONFIG_QUOTA_NETLINK_INTERFACE=y
> # CONFIG_PRINT_QUOTA_WARNING is not set
> # CONFIG_QUOTA_DEBUG is not set
> CONFIG_QUOTA_TREE=y
> # CONFIG_QFMT_V1 is not set
> CONFIG_QFMT_V2=y
> CONFIG_QUOTACTL=y
> CONFIG_QUOTACTL_COMPAT=y
> CONFIG_AUTOFS4_FS=y
> # CONFIG_FUSE_FS is not set
> # CONFIG_OVERLAY_FS is not set
>
> #
> # Caches
> #
> # CONFIG_FSCACHE is not set
>
> #
> # CD-ROM/DVD Filesystems
> #
> CONFIG_ISO9660_FS=y
> CONFIG_JOLIET=y
> CONFIG_ZISOFS=y
> # CONFIG_UDF_FS is not set
>
> #
> # DOS/FAT/NT Filesystems
> #
> CONFIG_FAT_FS=y
> CONFIG_MSDOS_FS=y
> CONFIG_VFAT_FS=y
> CONFIG_FAT_DEFAULT_CODEPAGE=437
> CONFIG_FAT_DEFAULT_IOCHARSET="iso8859-1"
> # CONFIG_NTFS_FS is not set
>
> #
> # Pseudo filesystems
> #
> CONFIG_PROC_FS=y
> CONFIG_PROC_KCORE=y
> CONFIG_PROC_VMCORE=y
> CONFIG_PROC_SYSCTL=y
> CONFIG_PROC_PAGE_MONITOR=y
> # CONFIG_PROC_CHILDREN is not set
> CONFIG_KERNFS=y
> CONFIG_SYSFS=y
> CONFIG_TMPFS=y
> CONFIG_TMPFS_POSIX_ACL=y
> CONFIG_TMPFS_XATTR=y
> CONFIG_HUGETLBFS=y
> CONFIG_HUGETLB_PAGE=y
> # CONFIG_CONFIGFS_FS is not set
> CONFIG_EFIVAR_FS=m
> CONFIG_MISC_FILESYSTEMS=y
> # CONFIG_ADFS_FS is not set
> # CONFIG_AFFS_FS is not set
> # CONFIG_ECRYPT_FS is not set
> # CONFIG_HFS_FS is not set
> # CONFIG_HFSPLUS_FS is not set
> # CONFIG_BEFS_FS is not set
> # CONFIG_BFS_FS is not set
> # CONFIG_EFS_FS is not set
> # CONFIG_LOGFS is not set
> # CONFIG_CRAMFS is not set
> # CONFIG_SQUASHFS is not set
> # CONFIG_VXFS_FS is not set
> # CONFIG_MINIX_FS is not set
> # CONFIG_OMFS_FS is not set
> # CONFIG_HPFS_FS is not set
> # CONFIG_QNX4FS_FS is not set
> # CONFIG_QNX6FS_FS is not set
> # CONFIG_ROMFS_FS is not set
> # CONFIG_PSTORE is not set
> # CONFIG_SYSV_FS is not set
> # CONFIG_UFS_FS is not set
> CONFIG_NETWORK_FILESYSTEMS=y
> CONFIG_NFS_FS=y
> CONFIG_NFS_V2=y
> CONFIG_NFS_V3=y
> CONFIG_NFS_V3_ACL=y
> CONFIG_NFS_V4=y
> # CONFIG_NFS_SWAP is not set
> # CONFIG_NFS_V4_1 is not set
> CONFIG_ROOT_NFS=y
> # CONFIG_NFS_USE_LEGACY_DNS is not set
> CONFIG_NFS_USE_KERNEL_DNS=y
> # CONFIG_NFSD is not set
> CONFIG_GRACE_PERIOD=y
> CONFIG_LOCKD=y
> CONFIG_LOCKD_V4=y
> CONFIG_NFS_ACL_SUPPORT=y
> CONFIG_NFS_COMMON=y
> CONFIG_SUNRPC=y
> CONFIG_SUNRPC_GSS=y
> # CONFIG_SUNRPC_DEBUG is not set
> # CONFIG_CEPH_FS is not set
> # CONFIG_CIFS is not set
> # CONFIG_NCP_FS is not set
> # CONFIG_CODA_FS is not set
> # CONFIG_AFS_FS is not set
> CONFIG_NLS=y
> CONFIG_NLS_DEFAULT="utf8"
> CONFIG_NLS_CODEPAGE_437=y
> # CONFIG_NLS_CODEPAGE_737 is not set
> # CONFIG_NLS_CODEPAGE_775 is not set
> # CONFIG_NLS_CODEPAGE_850 is not set
> # CONFIG_NLS_CODEPAGE_852 is not set
> # CONFIG_NLS_CODEPAGE_855 is not set
> # CONFIG_NLS_CODEPAGE_857 is not set
> # CONFIG_NLS_CODEPAGE_860 is not set
> # CONFIG_NLS_CODEPAGE_861 is not set
> # CONFIG_NLS_CODEPAGE_862 is not set
> # CONFIG_NLS_CODEPAGE_863 is not set
> # CONFIG_NLS_CODEPAGE_864 is not set
> # CONFIG_NLS_CODEPAGE_865 is not set
> # CONFIG_NLS_CODEPAGE_866 is not set
> # CONFIG_NLS_CODEPAGE_869 is not set
> # CONFIG_NLS_CODEPAGE_936 is not set
> # CONFIG_NLS_CODEPAGE_950 is not set
> # CONFIG_NLS_CODEPAGE_932 is not set
> # CONFIG_NLS_CODEPAGE_949 is not set
> # CONFIG_NLS_CODEPAGE_874 is not set
> # CONFIG_NLS_ISO8859_8 is not set
> # CONFIG_NLS_CODEPAGE_1250 is not set
> # CONFIG_NLS_CODEPAGE_1251 is not set
> CONFIG_NLS_ASCII=y
> CONFIG_NLS_ISO8859_1=y
> # CONFIG_NLS_ISO8859_2 is not set
> # CONFIG_NLS_ISO8859_3 is not set
> # CONFIG_NLS_ISO8859_4 is not set
> # CONFIG_NLS_ISO8859_5 is not set
> # CONFIG_NLS_ISO8859_6 is not set
> # CONFIG_NLS_ISO8859_7 is not set
> # CONFIG_NLS_ISO8859_9 is not set
> # CONFIG_NLS_ISO8859_13 is not set
> # CONFIG_NLS_ISO8859_14 is not set
> # CONFIG_NLS_ISO8859_15 is not set
> # CONFIG_NLS_KOI8_R is not set
> # CONFIG_NLS_KOI8_U is not set
> # CONFIG_NLS_MAC_ROMAN is not set
> # CONFIG_NLS_MAC_CELTIC is not set
> # CONFIG_NLS_MAC_CENTEURO is not set
> # CONFIG_NLS_MAC_CROATIAN is not set
> # CONFIG_NLS_MAC_CYRILLIC is not set
> # CONFIG_NLS_MAC_GAELIC is not set
> # CONFIG_NLS_MAC_GREEK is not set
> # CONFIG_NLS_MAC_ICELAND is not set
> # CONFIG_NLS_MAC_INUIT is not set
> # CONFIG_NLS_MAC_ROMANIAN is not set
> # CONFIG_NLS_MAC_TURKISH is not set
> CONFIG_NLS_UTF8=y
>
> #
> # Kernel hacking
> #
> CONFIG_TRACE_IRQFLAGS_SUPPORT=y
>
> #
> # printk and dmesg options
> #
> CONFIG_PRINTK_TIME=y
> CONFIG_MESSAGE_LOGLEVEL_DEFAULT=4
> # CONFIG_BOOT_PRINTK_DELAY is not set
> # CONFIG_DYNAMIC_DEBUG is not set
>
> #
> # Compile-time checks and compiler options
> #
> # CONFIG_DEBUG_INFO is not set
> # CONFIG_ENABLE_WARN_DEPRECATED is not set
> CONFIG_ENABLE_MUST_CHECK=y
> CONFIG_FRAME_WARN=2048
> # CONFIG_STRIP_ASM_SYMS is not set
> # CONFIG_READABLE_ASM is not set
> # CONFIG_UNUSED_SYMBOLS is not set
> # CONFIG_PAGE_OWNER is not set
> CONFIG_DEBUG_FS=y
> # CONFIG_HEADERS_CHECK is not set
> # CONFIG_DEBUG_SECTION_MISMATCH is not set
> CONFIG_SECTION_MISMATCH_WARN_ONLY=y
> CONFIG_ARCH_WANT_FRAME_POINTERS=y
> CONFIG_FRAME_POINTER=y
> # CONFIG_DEBUG_FORCE_WEAK_PER_CPU is not set
> CONFIG_MAGIC_SYSRQ=y
> CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE=0x1
> CONFIG_DEBUG_KERNEL=y
>
> #
> # Memory Debugging
> #
> # CONFIG_PAGE_EXTENSION is not set
> # CONFIG_DEBUG_PAGEALLOC is not set
> # CONFIG_DEBUG_OBJECTS is not set
> # CONFIG_SLUB_DEBUG_ON is not set
> # CONFIG_SLUB_STATS is not set
> CONFIG_HAVE_DEBUG_KMEMLEAK=y
> # CONFIG_DEBUG_KMEMLEAK is not set
> CONFIG_DEBUG_STACK_USAGE=y
> # CONFIG_DEBUG_VM is not set
> # CONFIG_DEBUG_VIRTUAL is not set
> CONFIG_DEBUG_MEMORY_INIT=y
> # CONFIG_DEBUG_PER_CPU_MAPS is not set
> CONFIG_HAVE_DEBUG_STACKOVERFLOW=y
> CONFIG_DEBUG_STACKOVERFLOW=y
> CONFIG_HAVE_ARCH_KMEMCHECK=y
> # CONFIG_KMEMCHECK is not set
> CONFIG_HAVE_ARCH_KASAN=y
> # CONFIG_KASAN is not set
> # CONFIG_DEBUG_SHIRQ is not set
>
> #
> # Debug Lockups and Hangs
> #
> # CONFIG_LOCKUP_DETECTOR is not set
> # CONFIG_DETECT_HUNG_TASK is not set
> # CONFIG_WQ_WATCHDOG is not set
> # CONFIG_PANIC_ON_OOPS is not set
> CONFIG_PANIC_ON_OOPS_VALUE=0
> CONFIG_PANIC_TIMEOUT=0
> # CONFIG_SCHED_DEBUG is not set
> CONFIG_SCHED_INFO=y
> CONFIG_SCHEDSTATS=y
> # CONFIG_SCHED_STACK_END_CHECK is not set
> # CONFIG_DEBUG_TIMEKEEPING is not set
> CONFIG_TIMER_STATS=y
> CONFIG_DEBUG_PREEMPT=y
>
> #
> # Lock Debugging (spinlocks, mutexes, etc...)
> #
> # CONFIG_DEBUG_RT_MUTEXES is not set
> CONFIG_DEBUG_SPINLOCK=y
> CONFIG_DEBUG_MUTEXES=y
> # CONFIG_DEBUG_WW_MUTEX_SLOWPATH is not set
> # CONFIG_DEBUG_LOCK_ALLOC is not set
> # CONFIG_PROVE_LOCKING is not set
> # CONFIG_LOCK_STAT is not set
> # CONFIG_DEBUG_ATOMIC_SLEEP is not set
> # CONFIG_DEBUG_LOCKING_API_SELFTESTS is not set
> # CONFIG_LOCK_TORTURE_TEST is not set
> CONFIG_STACKTRACE=y
> # CONFIG_DEBUG_KOBJECT is not set
> CONFIG_DEBUG_BUGVERBOSE=y
> # CONFIG_DEBUG_LIST is not set
> # CONFIG_DEBUG_PI_LIST is not set
> # CONFIG_DEBUG_SG is not set
> # CONFIG_DEBUG_NOTIFIERS is not set
> # CONFIG_DEBUG_CREDENTIALS is not set
>
> #
> # RCU Debugging
> #
> # CONFIG_PROVE_RCU is not set
> # CONFIG_SPARSE_RCU_POINTER is not set
> CONFIG_TORTURE_TEST=y
> CONFIG_RCU_TORTURE_TEST=y
> CONFIG_RCU_TORTURE_TEST_RUNNABLE=y
> CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT=y
> CONFIG_RCU_TORTURE_TEST_SLOW_PREINIT_DELAY=3
> CONFIG_RCU_TORTURE_TEST_SLOW_INIT=y
> CONFIG_RCU_TORTURE_TEST_SLOW_INIT_DELAY=3
> CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP=y
> CONFIG_RCU_TORTURE_TEST_SLOW_CLEANUP_DELAY=3
> CONFIG_RCU_CPU_STALL_TIMEOUT=21
> CONFIG_RCU_TRACE=y
> # CONFIG_RCU_EQS_DEBUG is not set
> # CONFIG_DEBUG_BLOCK_EXT_DEVT is not set
> # CONFIG_NOTIFIER_ERROR_INJECTION is not set
> # CONFIG_FAULT_INJECTION is not set
> # CONFIG_LATENCYTOP is not set
> CONFIG_ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS=y
> # CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is not set
> CONFIG_USER_STACKTRACE_SUPPORT=y
> CONFIG_NOP_TRACER=y
> CONFIG_HAVE_FUNCTION_TRACER=y
> CONFIG_HAVE_FUNCTION_GRAPH_TRACER=y
> CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST=y
> CONFIG_HAVE_DYNAMIC_FTRACE=y
> CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS=y
> CONFIG_HAVE_FTRACE_MCOUNT_RECORD=y
> CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
> CONFIG_HAVE_FENTRY=y
> CONFIG_HAVE_C_RECORDMCOUNT=y
> CONFIG_TRACE_CLOCK=y
> CONFIG_RING_BUFFER=y
> CONFIG_EVENT_TRACING=y
> CONFIG_CONTEXT_SWITCH_TRACER=y
> CONFIG_TRACING=y
> CONFIG_GENERIC_TRACER=y
> CONFIG_TRACING_SUPPORT=y
> CONFIG_FTRACE=y
> # CONFIG_FUNCTION_TRACER is not set
> # CONFIG_IRQSOFF_TRACER is not set
> # CONFIG_PREEMPT_TRACER is not set
> # CONFIG_SCHED_TRACER is not set
> # CONFIG_FTRACE_SYSCALLS is not set
> # CONFIG_TRACER_SNAPSHOT is not set
> CONFIG_BRANCH_PROFILE_NONE=y
> # CONFIG_PROFILE_ANNOTATED_BRANCHES is not set
> # CONFIG_PROFILE_ALL_BRANCHES is not set
> # CONFIG_STACK_TRACER is not set
> CONFIG_BLK_DEV_IO_TRACE=y
> CONFIG_KPROBE_EVENT=y
> # CONFIG_UPROBE_EVENT is not set
> CONFIG_PROBE_EVENTS=y
> # CONFIG_FTRACE_STARTUP_TEST is not set
> # CONFIG_MMIOTRACE is not set
> # CONFIG_TRACEPOINT_BENCHMARK is not set
> # CONFIG_RING_BUFFER_BENCHMARK is not set
> # CONFIG_RING_BUFFER_STARTUP_TEST is not set
> # CONFIG_TRACE_ENUM_MAP_FILE is not set
>
> #
> # Runtime Testing
> #
> # CONFIG_LKDTM is not set
> # CONFIG_TEST_LIST_SORT is not set
> # CONFIG_KPROBES_SANITY_TEST is not set
> # CONFIG_BACKTRACE_SELF_TEST is not set
> # CONFIG_RBTREE_TEST is not set
> # CONFIG_INTERVAL_TREE_TEST is not set
> # CONFIG_PERCPU_TEST is not set
> # CONFIG_ATOMIC64_SELFTEST is not set
> # CONFIG_TEST_HEXDUMP is not set
> # CONFIG_TEST_STRING_HELPERS is not set
> # CONFIG_TEST_KSTRTOX is not set
> # CONFIG_TEST_PRINTF is not set
> # CONFIG_TEST_RHASHTABLE is not set
> CONFIG_PROVIDE_OHCI1394_DMA_INIT=y
> # CONFIG_DMA_API_DEBUG is not set
> # CONFIG_TEST_LKM is not set
> # CONFIG_TEST_USER_COPY is not set
> # CONFIG_TEST_BPF is not set
> # CONFIG_TEST_FIRMWARE is not set
> # CONFIG_TEST_UDELAY is not set
> # CONFIG_MEMTEST is not set
> # CONFIG_TEST_STATIC_KEYS is not set
> # CONFIG_SAMPLES is not set
> CONFIG_HAVE_ARCH_KGDB=y
> # CONFIG_KGDB is not set
> CONFIG_ARCH_HAS_UBSAN_SANITIZE_ALL=y
> # CONFIG_UBSAN is not set
> CONFIG_ARCH_HAS_DEVMEM_IS_ALLOWED=y
> # CONFIG_STRICT_DEVMEM is not set
> CONFIG_X86_VERBOSE_BOOTUP=y
> CONFIG_EARLY_PRINTK=y
> CONFIG_EARLY_PRINTK_DBGP=y
> # CONFIG_EARLY_PRINTK_EFI is not set
> # CONFIG_X86_PTDUMP_CORE is not set
> # CONFIG_X86_PTDUMP is not set
> # CONFIG_EFI_PGT_DUMP is not set
> CONFIG_DEBUG_RODATA=y
> # CONFIG_DEBUG_RODATA_TEST is not set
> # CONFIG_DEBUG_WX is not set
> # CONFIG_DEBUG_SET_MODULE_RONX is not set
> # CONFIG_DEBUG_NX_TEST is not set
> CONFIG_DOUBLEFAULT=y
> # CONFIG_DEBUG_TLBFLUSH is not set
> # CONFIG_IOMMU_STRESS is not set
> CONFIG_HAVE_MMIOTRACE_SUPPORT=y
> # CONFIG_X86_DECODER_SELFTEST is not set
> CONFIG_IO_DELAY_TYPE_0X80=0
> CONFIG_IO_DELAY_TYPE_0XED=1
> CONFIG_IO_DELAY_TYPE_UDELAY=2
> CONFIG_IO_DELAY_TYPE_NONE=3
> CONFIG_IO_DELAY_0X80=y
> # CONFIG_IO_DELAY_0XED is not set
> # CONFIG_IO_DELAY_UDELAY is not set
> # CONFIG_IO_DELAY_NONE is not set
> CONFIG_DEFAULT_IO_DELAY_TYPE=0
> CONFIG_DEBUG_BOOT_PARAMS=y
> # CONFIG_CPA_DEBUG is not set
> CONFIG_OPTIMIZE_INLINING=y
> # CONFIG_DEBUG_ENTRY is not set
> # CONFIG_DEBUG_NMI_SELFTEST is not set
> # CONFIG_X86_DEBUG_STATIC_CPU_HAS is not set
> CONFIG_X86_DEBUG_FPU=y
> # CONFIG_PUNIT_ATOM_DEBUG is not set
>
> #
> # Security options
> #
> CONFIG_KEYS=y
> # CONFIG_PERSISTENT_KEYRINGS is not set
> # CONFIG_BIG_KEYS is not set
> # CONFIG_ENCRYPTED_KEYS is not set
> # CONFIG_SECURITY_DMESG_RESTRICT is not set
> CONFIG_SECURITY=y
> # CONFIG_SECURITYFS is not set
> CONFIG_SECURITY_NETWORK=y
> # CONFIG_SECURITY_NETWORK_XFRM is not set
> # CONFIG_SECURITY_PATH is not set
> # CONFIG_INTEL_TXT is not set
> CONFIG_LSM_MMAP_MIN_ADDR=65536
> CONFIG_SECURITY_SELINUX=y
> CONFIG_SECURITY_SELINUX_BOOTPARAM=y
> CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE=1
> CONFIG_SECURITY_SELINUX_DISABLE=y
> CONFIG_SECURITY_SELINUX_DEVELOP=y
> CONFIG_SECURITY_SELINUX_AVC_STATS=y
> CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE=0
> # CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX is not set
> # CONFIG_SECURITY_SMACK is not set
> # CONFIG_SECURITY_TOMOYO is not set
> # CONFIG_SECURITY_APPARMOR is not set
> # CONFIG_SECURITY_YAMA is not set
> CONFIG_INTEGRITY=y
> # CONFIG_INTEGRITY_SIGNATURE is not set
> CONFIG_INTEGRITY_AUDIT=y
> # CONFIG_IMA is not set
> # CONFIG_EVM is not set
> CONFIG_DEFAULT_SECURITY_SELINUX=y
> # CONFIG_DEFAULT_SECURITY_DAC is not set
> CONFIG_DEFAULT_SECURITY="selinux"
> CONFIG_CRYPTO=y
>
> #
> # Crypto core or helper
> #
> CONFIG_CRYPTO_ALGAPI=y
> CONFIG_CRYPTO_ALGAPI2=y
> CONFIG_CRYPTO_AEAD=y
> CONFIG_CRYPTO_AEAD2=y
> CONFIG_CRYPTO_BLKCIPHER=y
> CONFIG_CRYPTO_BLKCIPHER2=y
> CONFIG_CRYPTO_HASH=y
> CONFIG_CRYPTO_HASH2=y
> CONFIG_CRYPTO_RNG=y
> CONFIG_CRYPTO_RNG2=y
> CONFIG_CRYPTO_RNG_DEFAULT=y
> CONFIG_CRYPTO_PCOMP2=y
> CONFIG_CRYPTO_AKCIPHER2=y
> # CONFIG_CRYPTO_RSA is not set
> CONFIG_CRYPTO_MANAGER=y
> CONFIG_CRYPTO_MANAGER2=y
> # CONFIG_CRYPTO_USER is not set
> CONFIG_CRYPTO_MANAGER_DISABLE_TESTS=y
> CONFIG_CRYPTO_GF128MUL=y
> CONFIG_CRYPTO_NULL=y
> CONFIG_CRYPTO_NULL2=y
> # CONFIG_CRYPTO_PCRYPT is not set
> CONFIG_CRYPTO_WORKQUEUE=y
> # CONFIG_CRYPTO_CRYPTD is not set
> # CONFIG_CRYPTO_MCRYPTD is not set
> CONFIG_CRYPTO_AUTHENC=y
> # CONFIG_CRYPTO_TEST is not set
>
> #
> # Authenticated Encryption with Associated Data
> #
> CONFIG_CRYPTO_CCM=y
> CONFIG_CRYPTO_GCM=y
> # CONFIG_CRYPTO_CHACHA20POLY1305 is not set
> CONFIG_CRYPTO_SEQIV=y
> CONFIG_CRYPTO_ECHAINIV=y
>
> #
> # Block modes
> #
> CONFIG_CRYPTO_CBC=y
> CONFIG_CRYPTO_CTR=y
> # CONFIG_CRYPTO_CTS is not set
> # CONFIG_CRYPTO_ECB is not set
> # CONFIG_CRYPTO_LRW is not set
> # CONFIG_CRYPTO_PCBC is not set
> # CONFIG_CRYPTO_XTS is not set
> # CONFIG_CRYPTO_KEYWRAP is not set
>
> #
> # Hash modes
> #
> # CONFIG_CRYPTO_CMAC is not set
> CONFIG_CRYPTO_HMAC=y
> # CONFIG_CRYPTO_XCBC is not set
> # CONFIG_CRYPTO_VMAC is not set
>
> #
> # Digest
> #
> CONFIG_CRYPTO_CRC32C=y
> # CONFIG_CRYPTO_CRC32C_INTEL is not set
> # CONFIG_CRYPTO_CRC32 is not set
> # CONFIG_CRYPTO_CRC32_PCLMUL is not set
> # CONFIG_CRYPTO_CRCT10DIF is not set
> CONFIG_CRYPTO_GHASH=y
> # CONFIG_CRYPTO_POLY1305 is not set
> # CONFIG_CRYPTO_POLY1305_X86_64 is not set
> # CONFIG_CRYPTO_MD4 is not set
> CONFIG_CRYPTO_MD5=y
> # CONFIG_CRYPTO_MICHAEL_MIC is not set
> # CONFIG_CRYPTO_RMD128 is not set
> # CONFIG_CRYPTO_RMD160 is not set
> # CONFIG_CRYPTO_RMD256 is not set
> # CONFIG_CRYPTO_RMD320 is not set
> CONFIG_CRYPTO_SHA1=y
> # CONFIG_CRYPTO_SHA1_SSSE3 is not set
> # CONFIG_CRYPTO_SHA256_SSSE3 is not set
> # CONFIG_CRYPTO_SHA512_SSSE3 is not set
> # CONFIG_CRYPTO_SHA1_MB is not set
> CONFIG_CRYPTO_SHA256=y
> # CONFIG_CRYPTO_SHA512 is not set
> # CONFIG_CRYPTO_TGR192 is not set
> # CONFIG_CRYPTO_WP512 is not set
> # CONFIG_CRYPTO_GHASH_CLMUL_NI_INTEL is not set
>
> #
> # Ciphers
> #
> CONFIG_CRYPTO_AES=y
> # CONFIG_CRYPTO_AES_X86_64 is not set
> # CONFIG_CRYPTO_AES_NI_INTEL is not set
> # CONFIG_CRYPTO_ANUBIS is not set
> CONFIG_CRYPTO_ARC4=y
> # CONFIG_CRYPTO_BLOWFISH is not set
> # CONFIG_CRYPTO_BLOWFISH_X86_64 is not set
> # CONFIG_CRYPTO_CAMELLIA is not set
> # CONFIG_CRYPTO_CAMELLIA_X86_64 is not set
> # CONFIG_CRYPTO_CAMELLIA_AESNI_AVX_X86_64 is not set
> # CONFIG_CRYPTO_CAMELLIA_AESNI_AVX2_X86_64 is not set
> # CONFIG_CRYPTO_CAST5 is not set
> # CONFIG_CRYPTO_CAST5_AVX_X86_64 is not set
> # CONFIG_CRYPTO_CAST6 is not set
> # CONFIG_CRYPTO_CAST6_AVX_X86_64 is not set
> CONFIG_CRYPTO_DES=y
> # CONFIG_CRYPTO_DES3_EDE_X86_64 is not set
> # CONFIG_CRYPTO_FCRYPT is not set
> # CONFIG_CRYPTO_KHAZAD is not set
> # CONFIG_CRYPTO_SALSA20 is not set
> # CONFIG_CRYPTO_SALSA20_X86_64 is not set
> # CONFIG_CRYPTO_CHACHA20 is not set
> # CONFIG_CRYPTO_CHACHA20_X86_64 is not set
> # CONFIG_CRYPTO_SEED is not set
> # CONFIG_CRYPTO_SERPENT is not set
> # CONFIG_CRYPTO_SERPENT_SSE2_X86_64 is not set
> # CONFIG_CRYPTO_SERPENT_AVX_X86_64 is not set
> # CONFIG_CRYPTO_SERPENT_AVX2_X86_64 is not set
> # CONFIG_CRYPTO_TEA is not set
> # CONFIG_CRYPTO_TWOFISH is not set
> # CONFIG_CRYPTO_TWOFISH_X86_64 is not set
> # CONFIG_CRYPTO_TWOFISH_X86_64_3WAY is not set
> # CONFIG_CRYPTO_TWOFISH_AVX_X86_64 is not set
>
> #
> # Compression
> #
> # CONFIG_CRYPTO_DEFLATE is not set
> # CONFIG_CRYPTO_ZLIB is not set
> # CONFIG_CRYPTO_LZO is not set
> # CONFIG_CRYPTO_842 is not set
> # CONFIG_CRYPTO_LZ4 is not set
> # CONFIG_CRYPTO_LZ4HC is not set
>
> #
> # Random Number Generation
> #
> # CONFIG_CRYPTO_ANSI_CPRNG is not set
> CONFIG_CRYPTO_DRBG_MENU=y
> CONFIG_CRYPTO_DRBG_HMAC=y
> # CONFIG_CRYPTO_DRBG_HASH is not set
> # CONFIG_CRYPTO_DRBG_CTR is not set
> CONFIG_CRYPTO_DRBG=y
> CONFIG_CRYPTO_JITTERENTROPY=y
> # CONFIG_CRYPTO_USER_API_HASH is not set
> # CONFIG_CRYPTO_USER_API_SKCIPHER is not set
> # CONFIG_CRYPTO_USER_API_RNG is not set
> # CONFIG_CRYPTO_USER_API_AEAD is not set
> CONFIG_CRYPTO_HW=y
> # CONFIG_CRYPTO_DEV_PADLOCK is not set
> # CONFIG_CRYPTO_DEV_CCP is not set
> # CONFIG_CRYPTO_DEV_QAT_DH895xCC is not set
> # CONFIG_CRYPTO_DEV_QAT_C3XXX is not set
> # CONFIG_CRYPTO_DEV_QAT_C62X is not set
> # CONFIG_CRYPTO_DEV_QAT_DH895xCCVF is not set
> # CONFIG_CRYPTO_DEV_QAT_C3XXXVF is not set
> # CONFIG_CRYPTO_DEV_QAT_C62XVF is not set
> # CONFIG_ASYMMETRIC_KEY_TYPE is not set
>
> #
> # Certificates for signature checking
> #
> # CONFIG_SYSTEM_TRUSTED_KEYRING is not set
> CONFIG_HAVE_KVM=y
> CONFIG_VIRTUALIZATION=y
> # CONFIG_KVM is not set
> CONFIG_BINARY_PRINTF=y
>
> #
> # Library routines
> #
> CONFIG_BITREVERSE=y
> # CONFIG_HAVE_ARCH_BITREVERSE is not set
> CONFIG_RATIONAL=y
> CONFIG_GENERIC_STRNCPY_FROM_USER=y
> CONFIG_GENERIC_STRNLEN_USER=y
> CONFIG_GENERIC_NET_UTILS=y
> CONFIG_GENERIC_FIND_FIRST_BIT=y
> CONFIG_GENERIC_PCI_IOMAP=y
> CONFIG_GENERIC_IOMAP=y
> CONFIG_GENERIC_IO=y
> CONFIG_ARCH_USE_CMPXCHG_LOCKREF=y
> CONFIG_ARCH_HAS_FAST_MULTIPLIER=y
> # CONFIG_CRC_CCITT is not set
> CONFIG_CRC16=y
> # CONFIG_CRC_T10DIF is not set
> # CONFIG_CRC_ITU_T is not set
> CONFIG_CRC32=y
> # CONFIG_CRC32_SELFTEST is not set
> CONFIG_CRC32_SLICEBY8=y
> # CONFIG_CRC32_SLICEBY4 is not set
> # CONFIG_CRC32_SARWATE is not set
> # CONFIG_CRC32_BIT is not set
> # CONFIG_CRC7 is not set
> # CONFIG_LIBCRC32C is not set
> # CONFIG_CRC8 is not set
> # CONFIG_AUDIT_ARCH_COMPAT_GENERIC is not set
> # CONFIG_RANDOM32_SELFTEST is not set
> CONFIG_ZLIB_INFLATE=y
> CONFIG_LZO_COMPRESS=y
> CONFIG_LZO_DECOMPRESS=y
> CONFIG_LZ4_DECOMPRESS=y
> CONFIG_XZ_DEC=y
> CONFIG_XZ_DEC_X86=y
> CONFIG_XZ_DEC_POWERPC=y
> CONFIG_XZ_DEC_IA64=y
> CONFIG_XZ_DEC_ARM=y
> CONFIG_XZ_DEC_ARMTHUMB=y
> CONFIG_XZ_DEC_SPARC=y
> CONFIG_XZ_DEC_BCJ=y
> # CONFIG_XZ_DEC_TEST is not set
> CONFIG_DECOMPRESS_GZIP=y
> CONFIG_DECOMPRESS_BZIP2=y
> CONFIG_DECOMPRESS_LZMA=y
> CONFIG_DECOMPRESS_XZ=y
> CONFIG_DECOMPRESS_LZO=y
> CONFIG_DECOMPRESS_LZ4=y
> CONFIG_GENERIC_ALLOCATOR=y
> CONFIG_INTERVAL_TREE=y
> CONFIG_ASSOCIATIVE_ARRAY=y
> CONFIG_HAS_IOMEM=y
> CONFIG_HAS_IOPORT_MAP=y
> CONFIG_HAS_DMA=y
> CONFIG_CHECK_SIGNATURE=y
> CONFIG_CPU_RMAP=y
> CONFIG_DQL=y
> CONFIG_GLOB=y
> # CONFIG_GLOB_SELFTEST is not set
> CONFIG_NLATTR=y
> CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE=y
> # CONFIG_CORDIC is not set
> # CONFIG_DDR is not set
> # CONFIG_IRQ_POLL is not set
> CONFIG_OID_REGISTRY=y
> CONFIG_UCS2_STRING=y
> CONFIG_FONT_SUPPORT=y
> # CONFIG_FONTS is not set
> CONFIG_FONT_8x8=y
> CONFIG_FONT_8x16=y
> # CONFIG_SG_SPLIT is not set
> CONFIG_ARCH_HAS_SG_CHAIN=y
> CONFIG_ARCH_HAS_PMEM_API=y
> CONFIG_ARCH_HAS_MMIO_FLUSH=y



2016-03-30 14:16:48

by Boqun Feng

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Wed, Mar 30, 2016 at 06:30:38AM -0700, Paul E. McKenney wrote:
[...]
> > >
> >
> > I ran several tests similar to this setup in a guest, the guest was
> > running in a 12-core Xeon X5690 host with kernel 4.4.5. The guest was
> > given 16 VCPUs and 2G memory.
> >
> > Rather than RCU stall warnings, I was able to see a bug like this nearly

To be accurate, I did see RCU stall warnings, after the NULL pointer
dereference, but for every run, the NULL pointer dereference always
happened first.

> > *everytime*:
> >
> > [ 308.291635] BUG: unable to handle kernel NULL pointer dereference at (null)
> > [ 308.292063] IP: [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
>
> New one on me!
>
> > [ 308.292063] PGD 0
> > [ 308.292063] Oops: 0002 [#1] PREEMPT SMP
> > [ 308.292063] Modules linked in:
> > [ 308.292063] CPU: 11 PID: 798 Comm: torture_onoff Not tainted 4.5.0-rc1+ #14
> > [ 308.292063] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.1-20160216_104851-anatol 04/01/2014
> > [ 308.292063] task: ffff88007cafcb00 ti: ffff88007c6f4000 task.ti: ffff88007c6f4000
> > [ 308.292063] RIP: 0010:[<ffffffff810b9452>] [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> > [ 308.292063] RSP: 0018:ffff88007c6f7c98 EFLAGS: 00010086
> > [ 308.292063] RAX: dead000000000200 RBX: ffff88007fb6cc00 RCX: ffff88007fa2cc00
> > [ 308.292063] RDX: 0000000000000000 RSI: ffff88007fa2d6d0 RDI: ffff88007fb6cc00
> > [ 308.292063] RBP: ffff88007c6f7cc0 R08: 0000000000000000 R09: ffffffff81e4d360
> > [ 308.292063] R10: ffffea0001f2daa0 R11: 0000000000000000 R12: ffff88007fa2d6d0
> > [ 308.292063] R13: ffff88007fb6cc00 R14: 000000000000000b R15: ffff88007fa2c420
> > [ 308.292063] FS: 0000000000000000(0000) GS:ffff88007fb60000(0000) knlGS:0000000000000000
> > [ 308.292063] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> > [ 308.292063] CR2: 0000000000000000 CR3: 0000000001e0f000 CR4: 00000000000006e0
> > [ 308.292063] Stack:
> > [ 308.292063] ffff88007fb6cc00 ffff88007fa2d6d8 ffff88007fa2dad0 ffff88007fa2d8d0
> > [ 308.292063] ffff88007fa2d4d8 ffff88007c6f7d08 ffffffff810b95c4 ffff88007fa2cc00
> > [ 308.292063] ffff88007fa2d648 00000000fffffff0 ffffffff81e4e0c0 0000000000000007
> > [ 308.292063] Call Trace:
> > [ 308.292063] [<ffffffff810b95c4>] timer_cpu_notify+0xe4/0x160
> > [ 308.292063] [<ffffffff81073ea5>] notifier_call_chain+0x45/0x70
> > [ 308.292063] [<ffffffff81073fc9>] __raw_notifier_call_chain+0x9/0x10
> > [ 308.292063] [<ffffffff8105759e>] cpu_notify_nofail+0x1e/0x30
> > [ 308.292063] [<ffffffff81057852>] _cpu_down+0x212/0x350
> > [ 308.292063] [<ffffffff810b3350>] ? __call_rcu.constprop.74+0x380/0x380
> > [ 308.292063] [<ffffffff810b33b0>] ? call_rcu_bh+0x20/0x20
> > [ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> > [ 308.292063] [<ffffffff810a8950>] ? __rcu_read_unlock+0x50/0x50
> > [ 308.292063] [<ffffffff810579bf>] cpu_down+0x2f/0x50
> > [ 308.292063] [<ffffffff811266b5>] torture_onoff+0x115/0x380
> > [ 308.292063] [<ffffffff811265a0>] ? torture_kthread_stopping+0x70/0x70
> > [ 308.292063] [<ffffffff810732f6>] kthread+0xd6/0xf0
> > [ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> > [ 308.292063] [<ffffffff818b499f>] ret_from_fork+0x3f/0x70
> > [ 308.292063] [<ffffffff81073220>] ? kthread_worker_fn+0x180/0x180
> > [ 308.292063] Code: 56 41 55 41 54 53 48 8b 06 44 8b 77 40 48 85 c0 74 53 49 89 fd 49 89 f4 4d 8b 3c 24 66 66 66 66 90 49 8b 07 49 8b 57 08 48 85 c0 <48> 89 02 74 04 48 89 50 08 48 b8 00 02 00 00 00 00 ad de 4c 89
> > [ 308.292063] RIP [<ffffffff810b9452>] migrate_timer_list+0x32/0xc0
> > [ 308.292063] RSP <ffff88007c6f7c98>
> > [ 308.292063] CR2: 0000000000000000
> > [ 308.292063] ---[ end trace 29cb5d70ad875872 ]---
> >
> >
> > I'm not sure whether this is relevant, maybe this was caused by my
> > setup? But I attach two kernel logs and my config in case this could
> > help us solve the problem.
> >
> > Another interesting I observed was that the time stamps of printk went
> > back in a while in some run, please note the log named "dmesg.1" in the
> > attachments.
>
> That can cause all sorts of problems, including RCU CPU stall warnings.
>
> So I see the following in dmesg.1, courtesy of:
>
> sed -e 's/].*$//' < /tmp/dmesg.1 | awk '{ if (oldtime != "" && oldtime > $2) print; oldtime = $2 }'
>
> 1.128644 -> 1.128642: Only two microseconds backwards, so not enough
> to cause a stall warning (need about 21 seconds for that).
> 1.143582 -> 1.143575: Seven microseconds backwards.
> 316.386056 -> 421.191446: 104.8 seconds backwards, plenty to cause
> all sorts of problems, including stall warnings.
> 311.122004 -> 316.338053: 5.2 seconds backwards, can cause all sorts
> of problems, but not likely stall warnings.
>
> > A quick analysis of this bug is the null dereference happened at:
> >
> > migrate_timer_list()
> > detach_timer();
> > __list_del();
> > WRITE_ONCE(*pprev, next); <- pprev is NULL
> >
> > This seems highly unlikely, but as I said, I hit this almost every time
> > after a few minutes of starting rcutoture.
>
> Looks like a malformed list, which does look quite ugly. No idea
> whether or not this could be related to backwards-going time, but
> fixing the backwards-going time is a good first step.
>
> > Any idea about whether this could be related to the RCU stall problem,
> > or this is another bug, or this actually happend by design for some
> > reasons?
>
> One of your backwards-time incidents could cause both the RCU CPU stall
> warnings and also the soft lockup I see there.
>
> If this is an older system, it might have an unreliable TSC. If the
> kernel is nevertheless using TSC, this sort of thing could happen.
> The usual advice is to boot using HPET, but perhaps others on the
> list have more specific advice.
>

I tried another run, the kernel was compiled with HPET=y and boot
parameters "hpet=force notsc" and I still hit the same problem, any
suggestion for me to go further to get rid of TSC's impact?

Kernel log attached.

Regards,
Boqun

> Thanx, Paul
>


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2016-03-30 14:55:52

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Tue, Mar 29, 2016 at 06:49:08AM -0700, Paul E. McKenney wrote:
> On Mon, Mar 28, 2016 at 05:28:14PM -0700, Paul E. McKenney wrote:
> > On Mon, Mar 28, 2016 at 05:25:18PM -0700, Paul E. McKenney wrote:
> > > On Mon, Mar 28, 2016 at 06:08:41AM -0700, Paul E. McKenney wrote:
> > > > On Mon, Mar 28, 2016 at 08:25:47AM +0200, Peter Zijlstra wrote:
> > > > > On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:
> > >
> > > [ . . . ]
> > >
> > > > > > OK, so I should instrument migration_call() if I get the repro rate up?
> > > > >
> > > > > Can do, maybe try the below first. (yes I know how long it all takes :/)
> > > >
> > > > OK, will run this today, then run calibration for last night's run this
> > > > evening.
>
> And of 18 two-hour runs, there were five failures, or about 28%.
> That said, I don't have even one significant digit on the failure rate,
> as 5 of 18 is within the 95% confidence limits for a failure probability
> as low as 12.5% and as high as 47%.

And after last night's run, this is narrowed down to between 23% and 38%,
which is close enough. Average is 30%, 18 failures in 60 runs.

Next step is to test Peter's patch some more. Might take a couple of
night's worth of runs to get statistical significance. After which
it will be time to rebase to 4.6-rc1.

Thanx, Paul

> However, the previous night's runs gave 7 failures in 24 two-hour runs,
> for about a 29% failure rate. There is thus a good probability that my
> disabling of TIF_POLLING_NRFLAG had no effect whatsoever, tantalizing
> though that possibility might have been.
>
> (FWIW, I use the pdf_binomial() and quantile_binomial() functions in
> maxima for computing this stuff. Similar stuff is no doubt available
> in other math/stat packages as well.)
>
> So we have bugs, but not much idea where they are. Situation normal.
>
> Other thoughts?
>
> Thanx, Paul
>
> > > And there was one failure out of ten runs. If last night's failure rate
> > > was typical (7 of 24), then I believe we can be about 87% confident that
> > > this change helped. That isn't all that confident, but...
> >
> > And, as Murphy would have it, the instrumentation didn't trigger. I just
> > got the usual stall-warning messages with a starving RCU grace-period
> > kthread.
> >
> > Thanx, Paul
> >
> > > Tested-by: Paul E. McKenney <[email protected]>
> > >
> > > So what to run tonight?
> > >
> > > The most sane approach would be to run stock in order to get a baseline
> > > failure rate. It is tempting to run more of Peter's patch, but part of
> > > the problem is that we don't know the current baseline.
> > >
> > > So baseline it is...
> > >
> > > Thanx, Paul
> > >
> > > > Speaking of which, last night's run (disabling TIF_POLLING_NRFLAG)
> > > > consisted of 24 two-hour runs. Six of them had hard hangs, and another
> > > > had a hang that eventually unhung of its own accord. I believe that this
> > > > is significantly fewer failures than from a stock kernel, but I could
> > > > be wrong, and it will take some serious testing to give statistical
> > > > confidence for whatever conclusion is correct.
> > > >
> > > > > > > The other interesting case would be resched_cpu(), which uses
> > > > > > > set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> > > > > > > atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> > > > > > > not set. If indeed not, it will send an IPI.
> > > > > > >
> > > > > > > This assumes the idle 'exit' path will do the same as the IPI does; and
> > > > > > > if you look at cpu_idle_loop() it does indeed do both
> > > > > > > preempt_fold_need_resched() and sched_ttwu_pending().
> > > > > > >
> > > > > > > Note that one cannot rely on irq_enter()/irq_exit() being called for the
> > > > > > > scheduler IPI.
> > > > > >
> > > > > > OK, thank you for the info! Any specific debug actions?
> > > > >
> > > > > Dunno, something like the below should bring visibility into the
> > > > > (lockless) wake_list thingy.
> > > > >
> > > > > So these trace_printk()s should happen between trace_sched_waking() and
> > > > > trace_sched_wakeup() (I've not fully read the thread, but ISTR you had
> > > > > some traces with these here thingies on).
> > > > >
> > > > > ---
> > > > > arch/x86/include/asm/bitops.h | 6 ++++--
> > > > > kernel/sched/core.c | 9 +++++++++
> > > > > 2 files changed, 13 insertions(+), 2 deletions(-)
> > > > >
> > > > > diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> > > > > index 7766d1cf096e..5345784d5e41 100644
> > > > > --- a/arch/x86/include/asm/bitops.h
> > > > > +++ b/arch/x86/include/asm/bitops.h
> > > > > @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> > > > > if (IS_IMMEDIATE(nr)) {
> > > > > asm volatile(LOCK_PREFIX "andb %1,%0"
> > > > > : CONST_MASK_ADDR(nr, addr)
> > > > > - : "iq" ((u8)~CONST_MASK(nr)));
> > > > > + : "iq" ((u8)~CONST_MASK(nr))
> > > > > + : "memory");
> > > > > } else {
> > > > > asm volatile(LOCK_PREFIX "btr %1,%0"
> > > > > : BITOP_ADDR(addr)
> > > > > - : "Ir" (nr));
> > > > > + : "Ir" (nr)
> > > > > + : "memory");
> > > > > }
> > > > > }
> > > >
> > > > Is the above addition of "memory" strictly for the debug below, or is
> > > > it also a potential fix?
> > > >
> > > > Starting it up regardless, but figured I should ask!
> > > >
> > > > Thanx, Paul
> > > >
> > > > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > > > > index 0b21e7a724e1..b446f73c530d 100644
> > > > > --- a/kernel/sched/core.c
> > > > > +++ b/kernel/sched/core.c
> > > > > @@ -1669,6 +1669,7 @@ void sched_ttwu_pending(void)
> > > > > while (llist) {
> > > > > p = llist_entry(llist, struct task_struct, wake_entry);
> > > > > llist = llist_next(llist);
> > > > > + trace_printk("waking %d\n", p->pid);
> > > > > ttwu_do_activate(rq, p, 0);
> > > > > }
> > > > >
> > > > > @@ -1719,6 +1720,7 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
> > > > > struct rq *rq = cpu_rq(cpu);
> > > > >
> > > > > if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
> > > > > + trace_printk("queued %d for waking on %d\n", p->pid, cpu);
> > > > > if (!set_nr_if_polling(rq->idle))
> > > > > smp_send_reschedule(cpu);
> > > > > else
> > > > > @@ -5397,10 +5399,17 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
> > > > > migrate_tasks(rq);
> > > > > BUG_ON(rq->nr_running != 1); /* the migration thread */
> > > > > raw_spin_unlock_irqrestore(&rq->lock, flags);
> > > > > +
> > > > > + /* really bad m'kay */
> > > > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > > > +
> > > > > break;
> > > > >
> > > > > case CPU_DEAD:
> > > > > calc_load_migrate(rq);
> > > > > +
> > > > > + /* more bad */
> > > > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > > > break;
> > > > > #endif
> > > > > }
> > > > >

2016-03-31 15:42:52

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Wed, Mar 30, 2016 at 07:55:47AM -0700, Paul E. McKenney wrote:
> On Tue, Mar 29, 2016 at 06:49:08AM -0700, Paul E. McKenney wrote:
> > On Mon, Mar 28, 2016 at 05:28:14PM -0700, Paul E. McKenney wrote:
> > > On Mon, Mar 28, 2016 at 05:25:18PM -0700, Paul E. McKenney wrote:
> > > > On Mon, Mar 28, 2016 at 06:08:41AM -0700, Paul E. McKenney wrote:
> > > > > On Mon, Mar 28, 2016 at 08:25:47AM +0200, Peter Zijlstra wrote:
> > > > > > On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:
> > > >
> > > > [ . . . ]
> > > >
> > > > > > > OK, so I should instrument migration_call() if I get the repro rate up?
> > > > > >
> > > > > > Can do, maybe try the below first. (yes I know how long it all takes :/)
> > > > >
> > > > > OK, will run this today, then run calibration for last night's run this
> > > > > evening.
> >
> > And of 18 two-hour runs, there were five failures, or about 28%.
> > That said, I don't have even one significant digit on the failure rate,
> > as 5 of 18 is within the 95% confidence limits for a failure probability
> > as low as 12.5% and as high as 47%.
>
> And after last night's run, this is narrowed down to between 23% and 38%,
> which is close enough. Average is 30%, 18 failures in 60 runs.
>
> Next step is to test Peter's patch some more. Might take a couple of
> night's worth of runs to get statistical significance. After which
> it will be time to rebase to 4.6-rc1.

And the first night was not so good: 6 failures out of 24 runs. Adding
this to the 1-of-10 earlier gets 7 failures of 34. Here are how things
stack up given the range of base failure estimates:

Low 95% bound of 23%: 84% confidence.

Actual measurement of 30%: 92% confidence.

High 95% bound of 38%: 98% confidence.

So there is still some chance that Peter's patch is helping. I will
run for one more evening, after which it will be time to move forward
to 4.6-rc1.

Thanx, Paul

> > However, the previous night's runs gave 7 failures in 24 two-hour runs,
> > for about a 29% failure rate. There is thus a good probability that my
> > disabling of TIF_POLLING_NRFLAG had no effect whatsoever, tantalizing
> > though that possibility might have been.
> >
> > (FWIW, I use the pdf_binomial() and quantile_binomial() functions in
> > maxima for computing this stuff. Similar stuff is no doubt available
> > in other math/stat packages as well.)
> >
> > So we have bugs, but not much idea where they are. Situation normal.
> >
> > Other thoughts?
> >
> > Thanx, Paul
> >
> > > > And there was one failure out of ten runs. If last night's failure rate
> > > > was typical (7 of 24), then I believe we can be about 87% confident that
> > > > this change helped. That isn't all that confident, but...
> > >
> > > And, as Murphy would have it, the instrumentation didn't trigger. I just
> > > got the usual stall-warning messages with a starving RCU grace-period
> > > kthread.
> > >
> > > Thanx, Paul
> > >
> > > > Tested-by: Paul E. McKenney <[email protected]>
> > > >
> > > > So what to run tonight?
> > > >
> > > > The most sane approach would be to run stock in order to get a baseline
> > > > failure rate. It is tempting to run more of Peter's patch, but part of
> > > > the problem is that we don't know the current baseline.
> > > >
> > > > So baseline it is...
> > > >
> > > > Thanx, Paul
> > > >
> > > > > Speaking of which, last night's run (disabling TIF_POLLING_NRFLAG)
> > > > > consisted of 24 two-hour runs. Six of them had hard hangs, and another
> > > > > had a hang that eventually unhung of its own accord. I believe that this
> > > > > is significantly fewer failures than from a stock kernel, but I could
> > > > > be wrong, and it will take some serious testing to give statistical
> > > > > confidence for whatever conclusion is correct.
> > > > >
> > > > > > > > The other interesting case would be resched_cpu(), which uses
> > > > > > > > set_nr_and_not_polling() to kick a remote cpu to call schedule(). It
> > > > > > > > atomically sets TIF_NEED_RESCHED and returns if TIF_POLLING_NRFLAG was
> > > > > > > > not set. If indeed not, it will send an IPI.
> > > > > > > >
> > > > > > > > This assumes the idle 'exit' path will do the same as the IPI does; and
> > > > > > > > if you look at cpu_idle_loop() it does indeed do both
> > > > > > > > preempt_fold_need_resched() and sched_ttwu_pending().
> > > > > > > >
> > > > > > > > Note that one cannot rely on irq_enter()/irq_exit() being called for the
> > > > > > > > scheduler IPI.
> > > > > > >
> > > > > > > OK, thank you for the info! Any specific debug actions?
> > > > > >
> > > > > > Dunno, something like the below should bring visibility into the
> > > > > > (lockless) wake_list thingy.
> > > > > >
> > > > > > So these trace_printk()s should happen between trace_sched_waking() and
> > > > > > trace_sched_wakeup() (I've not fully read the thread, but ISTR you had
> > > > > > some traces with these here thingies on).
> > > > > >
> > > > > > ---
> > > > > > arch/x86/include/asm/bitops.h | 6 ++++--
> > > > > > kernel/sched/core.c | 9 +++++++++
> > > > > > 2 files changed, 13 insertions(+), 2 deletions(-)
> > > > > >
> > > > > > diff --git a/arch/x86/include/asm/bitops.h b/arch/x86/include/asm/bitops.h
> > > > > > index 7766d1cf096e..5345784d5e41 100644
> > > > > > --- a/arch/x86/include/asm/bitops.h
> > > > > > +++ b/arch/x86/include/asm/bitops.h
> > > > > > @@ -112,11 +112,13 @@ clear_bit(long nr, volatile unsigned long *addr)
> > > > > > if (IS_IMMEDIATE(nr)) {
> > > > > > asm volatile(LOCK_PREFIX "andb %1,%0"
> > > > > > : CONST_MASK_ADDR(nr, addr)
> > > > > > - : "iq" ((u8)~CONST_MASK(nr)));
> > > > > > + : "iq" ((u8)~CONST_MASK(nr))
> > > > > > + : "memory");
> > > > > > } else {
> > > > > > asm volatile(LOCK_PREFIX "btr %1,%0"
> > > > > > : BITOP_ADDR(addr)
> > > > > > - : "Ir" (nr));
> > > > > > + : "Ir" (nr)
> > > > > > + : "memory");
> > > > > > }
> > > > > > }
> > > > >
> > > > > Is the above addition of "memory" strictly for the debug below, or is
> > > > > it also a potential fix?
> > > > >
> > > > > Starting it up regardless, but figured I should ask!
> > > > >
> > > > > Thanx, Paul
> > > > >
> > > > > > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > > > > > index 0b21e7a724e1..b446f73c530d 100644
> > > > > > --- a/kernel/sched/core.c
> > > > > > +++ b/kernel/sched/core.c
> > > > > > @@ -1669,6 +1669,7 @@ void sched_ttwu_pending(void)
> > > > > > while (llist) {
> > > > > > p = llist_entry(llist, struct task_struct, wake_entry);
> > > > > > llist = llist_next(llist);
> > > > > > + trace_printk("waking %d\n", p->pid);
> > > > > > ttwu_do_activate(rq, p, 0);
> > > > > > }
> > > > > >
> > > > > > @@ -1719,6 +1720,7 @@ static void ttwu_queue_remote(struct task_struct *p, int cpu)
> > > > > > struct rq *rq = cpu_rq(cpu);
> > > > > >
> > > > > > if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
> > > > > > + trace_printk("queued %d for waking on %d\n", p->pid, cpu);
> > > > > > if (!set_nr_if_polling(rq->idle))
> > > > > > smp_send_reschedule(cpu);
> > > > > > else
> > > > > > @@ -5397,10 +5399,17 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
> > > > > > migrate_tasks(rq);
> > > > > > BUG_ON(rq->nr_running != 1); /* the migration thread */
> > > > > > raw_spin_unlock_irqrestore(&rq->lock, flags);
> > > > > > +
> > > > > > + /* really bad m'kay */
> > > > > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > > > > +
> > > > > > break;
> > > > > >
> > > > > > case CPU_DEAD:
> > > > > > calc_load_migrate(rq);
> > > > > > +
> > > > > > + /* more bad */
> > > > > > + WARN_ON(!llist_empty(&rq->wake_list));
> > > > > > break;
> > > > > > #endif
> > > > > > }
> > > > > >

2016-04-03 08:19:04

by Paul E. McKenney

[permalink] [raw]
Subject: Re: rcu_preempt self-detected stall on CPU from 4.5-rc3, since 3.17

On Thu, Mar 31, 2016 at 08:42:55AM -0700, Paul E. McKenney wrote:
> On Wed, Mar 30, 2016 at 07:55:47AM -0700, Paul E. McKenney wrote:
> > On Tue, Mar 29, 2016 at 06:49:08AM -0700, Paul E. McKenney wrote:
> > > On Mon, Mar 28, 2016 at 05:28:14PM -0700, Paul E. McKenney wrote:
> > > > On Mon, Mar 28, 2016 at 05:25:18PM -0700, Paul E. McKenney wrote:
> > > > > On Mon, Mar 28, 2016 at 06:08:41AM -0700, Paul E. McKenney wrote:
> > > > > > On Mon, Mar 28, 2016 at 08:25:47AM +0200, Peter Zijlstra wrote:
> > > > > > > On Sun, Mar 27, 2016 at 02:06:41PM -0700, Paul E. McKenney wrote:
> > > > >
> > > > > [ . . . ]
> > > > >
> > > > > > > > OK, so I should instrument migration_call() if I get the repro rate up?
> > > > > > >
> > > > > > > Can do, maybe try the below first. (yes I know how long it all takes :/)
> > > > > >
> > > > > > OK, will run this today, then run calibration for last night's run this
> > > > > > evening.
> > >
> > > And of 18 two-hour runs, there were five failures, or about 28%.
> > > That said, I don't have even one significant digit on the failure rate,
> > > as 5 of 18 is within the 95% confidence limits for a failure probability
> > > as low as 12.5% and as high as 47%.
> >
> > And after last night's run, this is narrowed down to between 23% and 38%,
> > which is close enough. Average is 30%, 18 failures in 60 runs.
> >
> > Next step is to test Peter's patch some more. Might take a couple of
> > night's worth of runs to get statistical significance. After which
> > it will be time to rebase to 4.6-rc1.
>
> And the first night was not so good: 6 failures out of 24 runs. Adding
> this to the 1-of-10 earlier gets 7 failures of 34. Here are how things
> stack up given the range of base failure estimates:
>
> Low 95% bound of 23%: 84% confidence.
>
> Actual measurement of 30%: 92% confidence.
>
> High 95% bound of 38%: 98% confidence.
>
> So there is still some chance that Peter's patch is helping. I will
> run for one more evening, after which it will be time to move forward
> to 4.6-rc1.

And no luck reducing bounds. However, moving to 4.6-rc1 did get some
of the trace_printk() to print. The ftrace_dump()s resulted in RCU
CPU stall warnings, and the dumps were truncated due to test timeouts
in my scripting. (I need to make my scripts more patient when they
see an ftrace dump in progress, I guess.)

Here are the results:

http://www2.rdrop.com/users/paulmck/submission/TREE03.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.1.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.2.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.3.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.4.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.5.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.6.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.7.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.8.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.9.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.11.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.12.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.13.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.14.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.15.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.16.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.17.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.18.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.19.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.20.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.21.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.22.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.23.console.log.tgz
http://www2.rdrop.com/users/paulmck/submission/TREE03.24.console.log.tgz

The config is here:

http://www2.rdrop.com/users/paulmck/submission/config.tgz

More runs to measure 4.6-rc1 base error rate...

Thanx, Paul