2014-10-02 18:24:47

by Dave Jones

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

On Fri, Sep 26, 2014 at 01:46:59AM +0200, Frederic Weisbecker wrote:

> > > [<ffffffffa10f95f8>] hrtimer_try_to_cancel+0x58/0x1f0
> > > [<ffffffffa10f97aa>] hrtimer_cancel+0x1a/0x30
> > > [<ffffffffa110a0e7>] tick_nohz_restart+0x17/0x90
> > > [<ffffffffa110af38>] __tick_nohz_full_check+0xc8/0xe0
> > > [<ffffffffa110af5e>] nohz_full_kick_work_func+0xe/0x10
> > > [<ffffffffa117c9bf>] irq_work_run_list+0x4f/0x70
> > > [<ffffffffa117ca0a>] irq_work_run+0x2a/0x60
> > > [<ffffffffa10f82eb>] update_process_times+0x5b/0x70
> > > [<ffffffffa1109dc5>] tick_sched_handle.isra.21+0x25/0x60
> > > [<ffffffffa110a0b1>] tick_sched_timer+0x41/0x60
> > > [<ffffffffa10f8c71>] __run_hrtimer+0x81/0x480
> > > [<ffffffffa110a070>] ? tick_sched_do_timer+0x90/0x90
> > > [<ffffffffa10f9b27>] hrtimer_interrupt+0x107/0x260
> > > [<ffffffffa10331a4>] local_apic_timer_interrupt+0x34/0x60
> > > [<ffffffffa182734f>] smp_apic_timer_interrupt+0x3f/0x60
> > > [<ffffffffa182576f>] apic_timer_interrupt+0x6f/0x80
> >
> > hrtimer_interrupt
> > tick_sched_timer
> > tick_sched_handle
> > update_process_times
> > irq_work_run
> > irq_work_run_list
> > nohz_full_kick_work_func
> > __tick_nohz_full_check
> > tick_nohz_restart
> > hrtimer_cancel
> >
> > And that hrtimer_cancel is:
> >
> > static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
> > {
> > hrtimer_cancel(&ts->sched_timer);
> >
> > Now, that's really bad because we are in the timer callback of
> > ts->sched_timer. So hrtimer_cancel will loop forever waiting for the
> > callback to complete.
> >
> > Frederic !?!?
>
> Right, this patchset fixes it: "[PATCH 0/8] nohz: Fix nohz kick irq work on tick v3"
>
> I was about to make the pull request, the branch is acked by peterz.
> Would you like to pull it? It's all merge window material.
>
> git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> nohz/fixes-v3

I'm now hitting this with such regularity that it's preventing me from
tracking down other bugs. Can we get this merged soon please ?

Dave


2014-10-02 22:01:38

by Mike Lothian

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

I think this might be the bug I reported here
https://bugzilla.kernel.org/show_bug.cgi?id=84131

On 2 October 2014 19:24, Dave Jones <[email protected]> wrote:
> On Fri, Sep 26, 2014 at 01:46:59AM +0200, Frederic Weisbecker wrote:
>
> > > > [<ffffffffa10f95f8>] hrtimer_try_to_cancel+0x58/0x1f0
> > > > [<ffffffffa10f97aa>] hrtimer_cancel+0x1a/0x30
> > > > [<ffffffffa110a0e7>] tick_nohz_restart+0x17/0x90
> > > > [<ffffffffa110af38>] __tick_nohz_full_check+0xc8/0xe0
> > > > [<ffffffffa110af5e>] nohz_full_kick_work_func+0xe/0x10
> > > > [<ffffffffa117c9bf>] irq_work_run_list+0x4f/0x70
> > > > [<ffffffffa117ca0a>] irq_work_run+0x2a/0x60
> > > > [<ffffffffa10f82eb>] update_process_times+0x5b/0x70
> > > > [<ffffffffa1109dc5>] tick_sched_handle.isra.21+0x25/0x60
> > > > [<ffffffffa110a0b1>] tick_sched_timer+0x41/0x60
> > > > [<ffffffffa10f8c71>] __run_hrtimer+0x81/0x480
> > > > [<ffffffffa110a070>] ? tick_sched_do_timer+0x90/0x90
> > > > [<ffffffffa10f9b27>] hrtimer_interrupt+0x107/0x260
> > > > [<ffffffffa10331a4>] local_apic_timer_interrupt+0x34/0x60
> > > > [<ffffffffa182734f>] smp_apic_timer_interrupt+0x3f/0x60
> > > > [<ffffffffa182576f>] apic_timer_interrupt+0x6f/0x80
> > >
> > > hrtimer_interrupt
> > > tick_sched_timer
> > > tick_sched_handle
> > > update_process_times
> > > irq_work_run
> > > irq_work_run_list
> > > nohz_full_kick_work_func
> > > __tick_nohz_full_check
> > > tick_nohz_restart
> > > hrtimer_cancel
> > >
> > > And that hrtimer_cancel is:
> > >
> > > static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
> > > {
> > > hrtimer_cancel(&ts->sched_timer);
> > >
> > > Now, that's really bad because we are in the timer callback of
> > > ts->sched_timer. So hrtimer_cancel will loop forever waiting for the
> > > callback to complete.
> > >
> > > Frederic !?!?
> >
> > Right, this patchset fixes it: "[PATCH 0/8] nohz: Fix nohz kick irq work on tick v3"
> >
> > I was about to make the pull request, the branch is acked by peterz.
> > Would you like to pull it? It's all merge window material.
> >
> > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > nohz/fixes-v3
>
> I'm now hitting this with such regularity that it's preventing me from
> tracking down other bugs. Can we get this merged soon please ?
>
> Dave
>
> --
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2014-10-07 15:30:31

by Frederic Weisbecker

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

On Thu, Oct 02, 2014 at 02:24:09PM -0400, Dave Jones wrote:
> On Fri, Sep 26, 2014 at 01:46:59AM +0200, Frederic Weisbecker wrote:
>
> > > > [<ffffffffa10f95f8>] hrtimer_try_to_cancel+0x58/0x1f0
> > > > [<ffffffffa10f97aa>] hrtimer_cancel+0x1a/0x30
> > > > [<ffffffffa110a0e7>] tick_nohz_restart+0x17/0x90
> > > > [<ffffffffa110af38>] __tick_nohz_full_check+0xc8/0xe0
> > > > [<ffffffffa110af5e>] nohz_full_kick_work_func+0xe/0x10
> > > > [<ffffffffa117c9bf>] irq_work_run_list+0x4f/0x70
> > > > [<ffffffffa117ca0a>] irq_work_run+0x2a/0x60
> > > > [<ffffffffa10f82eb>] update_process_times+0x5b/0x70
> > > > [<ffffffffa1109dc5>] tick_sched_handle.isra.21+0x25/0x60
> > > > [<ffffffffa110a0b1>] tick_sched_timer+0x41/0x60
> > > > [<ffffffffa10f8c71>] __run_hrtimer+0x81/0x480
> > > > [<ffffffffa110a070>] ? tick_sched_do_timer+0x90/0x90
> > > > [<ffffffffa10f9b27>] hrtimer_interrupt+0x107/0x260
> > > > [<ffffffffa10331a4>] local_apic_timer_interrupt+0x34/0x60
> > > > [<ffffffffa182734f>] smp_apic_timer_interrupt+0x3f/0x60
> > > > [<ffffffffa182576f>] apic_timer_interrupt+0x6f/0x80
> > >
> > > hrtimer_interrupt
> > > tick_sched_timer
> > > tick_sched_handle
> > > update_process_times
> > > irq_work_run
> > > irq_work_run_list
> > > nohz_full_kick_work_func
> > > __tick_nohz_full_check
> > > tick_nohz_restart
> > > hrtimer_cancel
> > >
> > > And that hrtimer_cancel is:
> > >
> > > static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
> > > {
> > > hrtimer_cancel(&ts->sched_timer);
> > >
> > > Now, that's really bad because we are in the timer callback of
> > > ts->sched_timer. So hrtimer_cancel will loop forever waiting for the
> > > callback to complete.
> > >
> > > Frederic !?!?
> >
> > Right, this patchset fixes it: "[PATCH 0/8] nohz: Fix nohz kick irq work on tick v3"
> >
> > I was about to make the pull request, the branch is acked by peterz.
> > Would you like to pull it? It's all merge window material.
> >
> > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > nohz/fixes-v3
>
> I'm now hitting this with such regularity that it's preventing me from
> tracking down other bugs. Can we get this merged soon please ?

I asked Thomas to pull but he probably missed it. So I did a formal pull request
to Ingo a few days later but he told me that the pull request was made too late
as the merge window was too close. I told him it fixes annoying bugs but that was on IRC
so this probably got lost.

It will probably be delayed to 3.18
Sorry I don't have much control myself on merging patches upstream.

2014-10-07 17:38:14

by Dave Jones

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

On Tue, Oct 07, 2014 at 05:30:27PM +0200, Frederic Weisbecker wrote:

> > > Right, this patchset fixes it: "[PATCH 0/8] nohz: Fix nohz kick irq work on tick v3"
> > >
> > > I was about to make the pull request, the branch is acked by peterz.
> > > Would you like to pull it? It's all merge window material.
> > >
> > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > > nohz/fixes-v3
> >
> > I'm now hitting this with such regularity that it's preventing me from
> > tracking down other bugs. Can we get this merged soon please ?
>
> I asked Thomas to pull but he probably missed it. So I did a formal pull request
> to Ingo a few days later but he told me that the pull request was made too late
> as the merge window was too close. I told him it fixes annoying bugs but that was on IRC
> so this probably got lost.
>
> It will probably be delayed to 3.18
> Sorry I don't have much control myself on merging patches upstream.

I got fed up of hitting it this morning and pull this into 3.17, and got
a bunch of rejects, as that tree is against rc5. Is there an updated
patchset somewhere else?

Dave

2014-10-07 17:49:35

by Thomas Gleixner

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

On Tue, 7 Oct 2014, Dave Jones wrote:

> On Tue, Oct 07, 2014 at 05:30:27PM +0200, Frederic Weisbecker wrote:
>
> > > > Right, this patchset fixes it: "[PATCH 0/8] nohz: Fix nohz kick irq work on tick v3"
> > > >
> > > > I was about to make the pull request, the branch is acked by peterz.
> > > > Would you like to pull it? It's all merge window material.
> > > >
> > > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > > > nohz/fixes-v3
> > >
> > > I'm now hitting this with such regularity that it's preventing me from
> > > tracking down other bugs. Can we get this merged soon please ?
> >
> > I asked Thomas to pull but he probably missed it. So I did a formal pull request
> > to Ingo a few days later but he told me that the pull request was made too late
> > as the merge window was too close. I told him it fixes annoying bugs but that was on IRC
> > so this probably got lost.

Aarg. Lemme get this done.

Thanks,

tglx

2014-10-09 02:03:25

by Dave Jones

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

On Tue, Oct 07, 2014 at 07:42:47PM +0200, Thomas Gleixner wrote:
> On Tue, 7 Oct 2014, Dave Jones wrote:
>
> > On Tue, Oct 07, 2014 at 05:30:27PM +0200, Frederic Weisbecker wrote:
> >
> > > > > Right, this patchset fixes it: "[PATCH 0/8] nohz: Fix nohz kick irq work on tick v3"
> > > > >
> > > > > I was about to make the pull request, the branch is acked by peterz.
> > > > > Would you like to pull it? It's all merge window material.
> > > > >
> > > > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > > > > nohz/fixes-v3
> > > >
> > > > I'm now hitting this with such regularity that it's preventing me from
> > > > tracking down other bugs. Can we get this merged soon please ?
> > >
> > > I asked Thomas to pull but he probably missed it. So I did a formal pull request
> > > to Ingo a few days later but he told me that the pull request was made too late
> > > as the merge window was too close. I told him it fixes annoying bugs but that was on IRC
> > > so this probably got lost.
>
> Aarg. Lemme get this done.

So, time for sad news.
This still doesn't solve the problem for me.

Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 2
CPU: 2 PID: 8193 Comm: kworker/u8:1 Not tainted 3.17.0+ #67
Workqueue: netns cleanup_net
0000000000000000 000000002a473fb8 ffff880244c06c00 ffffffff9f81ea56
ffffffff9fc63e00 ffff880244c06c80 ffffffff9f819003 0000000000000010
ffff880244c06c90 ffff880244c06c30 000000002a473fb8 0000000000000000
Call Trace:
<NMI> [<ffffffff9f81ea56>] dump_stack+0x4e/0x7a
[<ffffffff9f819003>] panic+0xd7/0x20a
[<ffffffff9f149f30>] ? restart_watchdog_hrtimer+0x50/0x50
[<ffffffff9f14a048>] watchdog_overflow_callback+0x118/0x120
[<ffffffff9f18b69c>] __perf_event_overflow+0xac/0x350
[<ffffffff9f019ece>] ? x86_perf_event_set_period+0xde/0x150
[<ffffffff9f18c5b4>] perf_event_overflow+0x14/0x20
[<ffffffff9f01fc26>] intel_pmu_handle_irq+0x206/0x410
[<ffffffff9f018d2b>] perf_event_nmi_handler+0x2b/0x50
[<ffffffff9f007752>] nmi_handle+0xd2/0x3b0
[<ffffffff9f007685>] ? nmi_handle+0x5/0x3b0
[<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
[<ffffffff9f007c62>] default_do_nmi+0x72/0x1c0
[<ffffffff9f0fd318>] ? hrtimer_try_to_cancel+0x58/0x1f0
[<ffffffff9f007e68>] do_nmi+0xb8/0xf0
[<ffffffff9f82c9ea>] end_repeat_nmi+0x1e/0x2e
[<ffffffff9f0fd318>] ? hrtimer_try_to_cancel+0x58/0x1f0
[<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
[<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
[<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
<<EOE>> <IRQ> [<ffffffff9f0cf880>] lock_release_holdtime.part.29+0x50/0x160
[<ffffffff9f0d4f75>] lock_release+0x235/0x300
[<ffffffff9f829bf4>] _raw_spin_unlock_irqrestore+0x24/0x70
[<ffffffff9f0fd318>] hrtimer_try_to_cancel+0x58/0x1f0
[<ffffffff9f0fd4ca>] hrtimer_cancel+0x1a/0x30
[<ffffffff9f10de07>] tick_nohz_restart+0x17/0x90
[<ffffffff9f10ec58>] __tick_nohz_full_check+0xc8/0xe0
[<ffffffff9f10ec7e>] nohz_full_kick_work_func+0xe/0x10
[<ffffffff9f1806df>] irq_work_run_list+0x4f/0x70
[<ffffffff9f18091b>] irq_work_tick+0x2b/0x50
[<ffffffff9f0fc00b>] update_process_times+0x5b/0x70
[<ffffffff9f10dae5>] tick_sched_handle.isra.21+0x25/0x60
[<ffffffff9f10ddd1>] tick_sched_timer+0x41/0x60
[<ffffffff9f0fc991>] __run_hrtimer+0x81/0x480
[<ffffffff9f10dd90>] ? tick_sched_do_timer+0x90/0x90
[<ffffffff9f0fd847>] hrtimer_interrupt+0x107/0x260
[<ffffffff9f033274>] local_apic_timer_interrupt+0x34/0x60
[<ffffffff9f82d48f>] smp_apic_timer_interrupt+0x3f/0x60
[<ffffffff9f82b8af>] apic_timer_interrupt+0x6f/0x80
<EOI> [<ffffffffc0415436>] ? cache_clean+0x66/0x2f0 [sunrpc]
[<ffffffffc04156f7>] cache_flush+0x37/0x70 [sunrpc]
[<ffffffffc041577f>] cache_purge+0x4f/0x80 [sunrpc]
[<ffffffffc040c80a>] svcauth_unix_purge+0xca/0x1c0 [sunrpc]
[<ffffffffc040c745>] ? svcauth_unix_purge+0x5/0x1c0 [sunrpc]
[<ffffffffc04d4f72>] nfsd_export_shutdown+0x112/0x250 [nfsd]
[<ffffffffc04d4e65>] ? nfsd_export_shutdown+0x5/0x250 [nfsd]
[<ffffffffc04c972a>] nfsd_exit_net+0x1a/0x20 [nfsd]
[<ffffffff9f6cdf39>] ops_exit_list.isra.1+0x39/0x60
[<ffffffff9f6ceae0>] cleanup_net+0x100/0x1e0
[<ffffffff9f097b30>] process_one_work+0x1e0/0x6b0
[<ffffffff9f097ac7>] ? process_one_work+0x177/0x6b0
[<ffffffff9f09811b>] worker_thread+0x11b/0x490
[<ffffffff9f098000>] ? process_one_work+0x6b0/0x6b0
[<ffffffff9f09ee46>] kthread+0xf6/0x110
[<ffffffff9f09ed50>] ? kthread_create_on_node+0x250/0x250
[<ffffffff9f82a8ac>] ret_from_fork+0x7c/0xb0
[<ffffffff9f09ed50>] ? kthread_create_on_node+0x250/0x250

Here's what I have on top of Linus' current tree..
http://paste.fedoraproject.org/140505/20075141/raw/

Do I miss some other essential patch ?

Dave

2014-10-09 03:30:34

by Frederic Weisbecker

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

On Wed, Oct 08, 2014 at 10:02:40PM -0400, Dave Jones wrote:
> On Tue, Oct 07, 2014 at 07:42:47PM +0200, Thomas Gleixner wrote:
> > On Tue, 7 Oct 2014, Dave Jones wrote:
> >
> > > On Tue, Oct 07, 2014 at 05:30:27PM +0200, Frederic Weisbecker wrote:
> > >
> > > > > > Right, this patchset fixes it: "[PATCH 0/8] nohz: Fix nohz kick irq work on tick v3"
> > > > > >
> > > > > > I was about to make the pull request, the branch is acked by peterz.
> > > > > > Would you like to pull it? It's all merge window material.
> > > > > >
> > > > > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
> > > > > > nohz/fixes-v3
> > > > >
> > > > > I'm now hitting this with such regularity that it's preventing me from
> > > > > tracking down other bugs. Can we get this merged soon please ?
> > > >
> > > > I asked Thomas to pull but he probably missed it. So I did a formal pull request
> > > > to Ingo a few days later but he told me that the pull request was made too late
> > > > as the merge window was too close. I told him it fixes annoying bugs but that was on IRC
> > > > so this probably got lost.
> >
> > Aarg. Lemme get this done.
>
> So, time for sad news.
> This still doesn't solve the problem for me.
>
> Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 2
> CPU: 2 PID: 8193 Comm: kworker/u8:1 Not tainted 3.17.0+ #67
> Workqueue: netns cleanup_net
> 0000000000000000 000000002a473fb8 ffff880244c06c00 ffffffff9f81ea56
> ffffffff9fc63e00 ffff880244c06c80 ffffffff9f819003 0000000000000010
> ffff880244c06c90 ffff880244c06c30 000000002a473fb8 0000000000000000
> Call Trace:
> <NMI> [<ffffffff9f81ea56>] dump_stack+0x4e/0x7a
> [<ffffffff9f819003>] panic+0xd7/0x20a
> [<ffffffff9f149f30>] ? restart_watchdog_hrtimer+0x50/0x50
> [<ffffffff9f14a048>] watchdog_overflow_callback+0x118/0x120
> [<ffffffff9f18b69c>] __perf_event_overflow+0xac/0x350
> [<ffffffff9f019ece>] ? x86_perf_event_set_period+0xde/0x150
> [<ffffffff9f18c5b4>] perf_event_overflow+0x14/0x20
> [<ffffffff9f01fc26>] intel_pmu_handle_irq+0x206/0x410
> [<ffffffff9f018d2b>] perf_event_nmi_handler+0x2b/0x50
> [<ffffffff9f007752>] nmi_handle+0xd2/0x3b0
> [<ffffffff9f007685>] ? nmi_handle+0x5/0x3b0
> [<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
> [<ffffffff9f007c62>] default_do_nmi+0x72/0x1c0
> [<ffffffff9f0fd318>] ? hrtimer_try_to_cancel+0x58/0x1f0
> [<ffffffff9f007e68>] do_nmi+0xb8/0xf0
> [<ffffffff9f82c9ea>] end_repeat_nmi+0x1e/0x2e
> [<ffffffff9f0fd318>] ? hrtimer_try_to_cancel+0x58/0x1f0
> [<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
> [<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
> [<ffffffff9f0cef39>] ? get_lock_stats+0x19/0x60
> <<EOE>> <IRQ> [<ffffffff9f0cf880>] lock_release_holdtime.part.29+0x50/0x160
> [<ffffffff9f0d4f75>] lock_release+0x235/0x300
> [<ffffffff9f829bf4>] _raw_spin_unlock_irqrestore+0x24/0x70
> [<ffffffff9f0fd318>] hrtimer_try_to_cancel+0x58/0x1f0
> [<ffffffff9f0fd4ca>] hrtimer_cancel+0x1a/0x30
> [<ffffffff9f10de07>] tick_nohz_restart+0x17/0x90
> [<ffffffff9f10ec58>] __tick_nohz_full_check+0xc8/0xe0
> [<ffffffff9f10ec7e>] nohz_full_kick_work_func+0xe/0x10
> [<ffffffff9f1806df>] irq_work_run_list+0x4f/0x70
> [<ffffffff9f18091b>] irq_work_tick+0x2b/0x50
> [<ffffffff9f0fc00b>] update_process_times+0x5b/0x70
> [<ffffffff9f10dae5>] tick_sched_handle.isra.21+0x25/0x60
> [<ffffffff9f10ddd1>] tick_sched_timer+0x41/0x60
> [<ffffffff9f0fc991>] __run_hrtimer+0x81/0x480
> [<ffffffff9f10dd90>] ? tick_sched_do_timer+0x90/0x90
> [<ffffffff9f0fd847>] hrtimer_interrupt+0x107/0x260
> [<ffffffff9f033274>] local_apic_timer_interrupt+0x34/0x60
> [<ffffffff9f82d48f>] smp_apic_timer_interrupt+0x3f/0x60
> [<ffffffff9f82b8af>] apic_timer_interrupt+0x6f/0x80
> <EOI> [<ffffffffc0415436>] ? cache_clean+0x66/0x2f0 [sunrpc]
> [<ffffffffc04156f7>] cache_flush+0x37/0x70 [sunrpc]
> [<ffffffffc041577f>] cache_purge+0x4f/0x80 [sunrpc]
> [<ffffffffc040c80a>] svcauth_unix_purge+0xca/0x1c0 [sunrpc]
> [<ffffffffc040c745>] ? svcauth_unix_purge+0x5/0x1c0 [sunrpc]
> [<ffffffffc04d4f72>] nfsd_export_shutdown+0x112/0x250 [nfsd]
> [<ffffffffc04d4e65>] ? nfsd_export_shutdown+0x5/0x250 [nfsd]
> [<ffffffffc04c972a>] nfsd_exit_net+0x1a/0x20 [nfsd]
> [<ffffffff9f6cdf39>] ops_exit_list.isra.1+0x39/0x60
> [<ffffffff9f6ceae0>] cleanup_net+0x100/0x1e0
> [<ffffffff9f097b30>] process_one_work+0x1e0/0x6b0
> [<ffffffff9f097ac7>] ? process_one_work+0x177/0x6b0
> [<ffffffff9f09811b>] worker_thread+0x11b/0x490
> [<ffffffff9f098000>] ? process_one_work+0x6b0/0x6b0
> [<ffffffff9f09ee46>] kthread+0xf6/0x110
> [<ffffffff9f09ed50>] ? kthread_create_on_node+0x250/0x250
> [<ffffffff9f82a8ac>] ret_from_fork+0x7c/0xb0
> [<ffffffff9f09ed50>] ? kthread_create_on_node+0x250/0x250
>
> Here's what I have on top of Linus' current tree..
> http://paste.fedoraproject.org/140505/20075141/raw/
>
> Do I miss some other essential patch ?

If you have used the diff in that URL then you've missed:

x86: Tell irq work about self IPI support

Without that the whole patchset has no effect.

2014-10-09 03:50:37

by Dave Jones

[permalink] [raw]
Subject: Re: hrtimer deadlock caused by nohz_full

On Thu, Oct 09, 2014 at 05:30:20AM +0200, Frederic Weisbecker wrote:

> > Do I miss some other essential patch ?
>
> If you have used the diff in that URL then you've missed:
>
> x86: Tell irq work about self IPI support
>
> Without that the whole patchset has no effect.

Ok. Thanks, I'll rerun with that.

Dave