Hello Thomas,
2009/4/3 Remy Bohmer <[email protected]>:
> Hello Thomas,
>
>>> Does anybody recognise these backtraces? And if so, is there a fix for
>>> it already?
>>
>> http://www.kernel.org/pub/linux/kernel/projects/rt/patch-2.6.24.7-rt27.bz2
I integrated -rt27, but this one fails on the locking api-selftests.
Is this a bug in the selftest? Or is there a real locking bug behind
it?
Kind regards,
Remy
[ 0.000000] Linux version 2.6.24.7-rt27 (bvdm@pc2-bvdm) (gcc
version 4.1.2 20070626 (Red Hat 4.1.2-13)) #11 SMP PREEMP
T RT Fri Apr 3 13:33:47 CEST 2009
[ 0.000000] BIOS-provided physical RAM map:
[ 0.000000] BIOS-e820: 0000000000000000 - 000000000009f800 (usable)
[ 0.000000] BIOS-e820: 000000000009f800 - 00000000000a0000 (reserved)
[ 0.000000] BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
[ 0.000000] BIOS-e820: 0000000000100000 - 000000007f6e0000 (usable)
[ 0.000000] BIOS-e820: 000000007f6e0000 - 000000007f6e7000 (ACPI data)
[ 0.000000] BIOS-e820: 000000007f6e7000 - 000000007f700000 (ACPI NVS)
[ 0.000000] BIOS-e820: 000000007f700000 - 0000000080000000 (reserved)
[ 0.000000] BIOS-e820: 00000000fec00000 - 00000000fed00000 (reserved)
[ 0.000000] BIOS-e820: 00000000fee00000 - 00000000fef00000 (reserved)
[ 0.000000] BIOS-e820: 00000000ffb80000 - 0000000100000000 (reserved)
[ 0.000000] console [earlyser0] enabled
[ 0.000000] 1142MB HIGHMEM available.
[ 0.000000] 896MB LOWMEM available.
[ 0.000000] found SMP MP-table at 000f7a00
[ 0.000000] Zone PFN ranges:
[ 0.000000] DMA 0 -> 4096
[ 0.000000] Normal 4096 -> 229376
[ 0.000000] HighMem 229376 -> 521952
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[1] active PFN ranges
[ 0.000000] 0: 0 -> 521952
[ 0.000000] DMI 2.4 present.
[ 0.000000] Using APIC driver default
[ 0.000000] ACPI: RSDP 000F7A30, 0024 (r2 PTLTD )
[ 0.000000] ACPI: XSDT 7F6E23E6, 0064 (r1 PTLTD XSDT 50000
LTP 0)
[ 0.000000] ACPI: FACP 7F6E24BE, 00F4 (r3 FSC 50000
F4240)
[ 0.000000] ACPI: DSDT 7F6E25B2, 475B (r1 FSC D2151 50000
MSFT 3000001)
[ 0.000000] ACPI: FACS 7F6E7FC0, 0040
[ 0.000000] ACPI: ASF! 7F6E6D0D, 0085 (r16 OEMID OEMTBL 50000
PTL 1)
[ 0.000000] ACPI: SSDT 7F6E6D92, 00B6 (r1 FSC EISTCPU0 50000
CSF 1)
[ 0.000000] ACPI: SSDT 7F6E6E48, 00B6 (r1 FSC EISTCPU1 50000
CSF 1)
[ 0.000000] ACPI: MCFG 7F6E6EFE, 0040 (r1 PTLTD MCFG 50000
LTP 0)
[ 0.000000] ACPI: HPET 7F6E6F3E, 0038 (r1 PTLTD HPETTBL 50000
LTP 1)
[ 0.000000] ACPI: APIC 7F6E6F76, 0062 (r1 FSC APIC 50000
CSF 0)
[ 0.000000] ACPI: BOOT 7F6E6FD8, 0028 (r1 PTLTD $SBFTBL$ 50000
LTP 1)
[ 0.000000] ACPI: DMI detected: Fujitsu Siemens
[ 0.000000] ACPI: PM-Timer IO Port: 0xf008
[ 0.000000] ACPI: LAPIC (acpi_id[0x00] lapic_id[0x00] enabled)
[ 0.000000] Processor #0 6:15 APIC version 20
[ 0.000000] ACPI: LAPIC (acpi_id[0x01] lapic_id[0x01] enabled)
[ 0.000000] Processor #1 6:15 APIC version 20
[ 0.000000] ACPI: LAPIC_NMI (acpi_id[0xff] high edge lint[0x1])
[ 0.000000] ACPI: IOAPIC (id[0x02] address[0xfec00000] gsi_base[0])
[ 0.000000] IOAPIC[0]: apic_id 2, version 32, address 0xfec00000, GSI 0-23
[ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 high edge)
[ 0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
[ 0.000000] Enabling APIC mode: Flat. Using 1 I/O APICs
[ 0.000000] ACPI: HPET id: 0x8086a201 base: 0xfed00000
[ 0.000000] Using ACPI (MADT) for SMP configuration information
[ 0.000000] Allocating PCI resources starting at 88000000 (gap:
80000000:7ec00000)
[ 0.000000] Real-Time Preemption Support (C) 2004-2007 Ingo Molnar
[ 0.000000] Built 1 zonelists in Zone order, mobility grouping on.
Total pages: 510229
[ 0.000000] Kernel command line: ro root=/dev/lvmbase/root1
printk.time=1 console=ttyS0,115200 earlyprintk=ttyS0,115200
clocksource=acpi_pm nodmraid
[ 0.000000] Enabling fast FPU save and restore... done.
[ 0.000000] Enabling unmasked SIMD FPU exception support... done.
[ 0.000000] Initializing CPU#0
[ 0.000000] PID hash table entries: 4096 (order: 12, 16384 bytes)
[ 0.000000] Detected 2128.085 MHz processor.
[ 84.043390] Console: colour VGA+ 80x25
[ 84.046954] Lock dependency validator: Copyright (c) 2006 Red Hat,
Inc., Ingo Molnar
[ 84.054653] ... MAX_LOCKDEP_SUBCLASSES: 8
[ 84.059065] ... MAX_LOCK_DEPTH: 30
[ 84.063477] ... MAX_LOCKDEP_KEYS: 2048
[ 84.067889] ... CLASSHASH_SIZE: 1024
[ 84.072301] ... MAX_LOCKDEP_ENTRIES: 16384
[ 84.076712] ... MAX_LOCKDEP_CHAINS: 32768
[ 84.081125] ... CHAINHASH_SIZE: 16384
[ 84.085537] memory used by lock dependency info: 1568 kB
[ 84.090901] per task-struct memory footprint: 1200 bytes
[ 84.096263] ------------------------
[ 84.099811] | Locking API testsuite:
[ 84.103358] ----------------------------------------------------------------------------
[ 84.111403] | spin |wlock |rlock
|mutex | wsem | rsem |
[ 84.119449]
--------------------------------------------------------------------------
[ 84.127498] A-A deadlock: ok | ok | ok |
ok | ok | ok |
[ 84.135539] A-B-B-A deadlock: ok | ok
|WARNING: at kernel/rtmutex.c:1311 try_to_take_rw_read()
[ 84.145922] Pid: 0, comm: swapper Not tainted 2.6.24.7-rt27 #11
[ 84.151803] [<c010655a>] show_trace_log_lvl+0x1a/0x30
[ 84.156908] [<c0106ff2>] show_trace+0x12/0x20
[ 84.161319] [<c010780c>] dump_stack+0x6c/0x80
[ 84.165731] [<c0156256>] try_to_take_rw_read+0x546/0x590
[ 84.171408] [<c0157330>] rt_read_slowlock+0x30/0x2e0
[ 84.176426] [<c0156f7a>] rt_rwlock_read_lock+0xa/0x10
[ 84.181531] [<c04c0c32>] rt_read_lock+0x32/0x40
[ 84.186115] [<c02cefa7>] ABBA_rlock+0x17/0x60
[ 84.190527] [<c02cda47>] dotest+0x27/0x400
[ 84.194680] [<c02cf93a>] locking_selftest+0x15a/0x8a0
[ 84.199785] [<c0658b0d>] start_kernel+0x25d/0x3b0
[ 84.204542] [<00000000>] 0x0
[ 84.207483] =======================
[ 84.211032] WARNING: at kernel/rtmutex.c:1704 rt_read_slowunlock()
[ 84.217172] Pid: 0, comm: swapper Not tainted 2.6.24.7-rt27 #11
[ 84.223055] [<c010655a>] show_trace_log_lvl+0x1a/0x30
[ 84.228159] [<c0106ff2>] show_trace+0x12/0x20
[ 84.232570] [<c010780c>] dump_stack+0x6c/0x80
[ 84.236983] [<c04bf855>] rt_read_slowunlock+0x2e5/0x4a0
[ 84.242259] [<c0156fb6>] rt_rwlock_read_unlock+0x26/0xb0
[ 84.247623] [<c04c0bdd>] rt_read_unlock+0x1d/0x20
[ 84.252381] [<c02cefb1>] ABBA_rlock+0x21/0x60
[ 84.256794] [<c02cda47>] dotest+0x27/0x400
[ 84.260946] [<c02cf93a>] locking_selftest+0x15a/0x8a0
[ 84.266051] [<c0658b0d>] start_kernel+0x25d/0x3b0
[ 84.270808] [<00000000>] 0x0
[ 84.273750] =======================
[ 84.277302] ok | ok | ok | ok |
[ 84.281190] A-B-B-C-C-A deadlock: ok | ok
|<0>------------[ cut here ]------------
[ 84.290187] kernel BUG at kernel/sched.c:4443!
[ 84.294598] invalid opcode: 0000 [#1] PREEMPT SMP
[ 84.299357] Modules linked in:
[ 84.302385]
[ 84.303856] Pid: 0, comm: swapper Not tainted (2.6.24.7-rt27 #11)
[ 84.309911] EIP: 0060:[<c012b900>] EFLAGS: 00010092 CPU: 0
[ 84.315361] EIP is at task_setprio+0x190/0x1c0
[ 84.319773] EAX: c04cbba0 EBX: c05fe500 ECX: efd2e7d2 EDX: efd2e7d2
[ 84.326002] ESI: c05fe500 EDI: c05fea38 EBP: c0653ef8 ESP: c0653ec0
[ 84.332230] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 preempt:00000003
[ 84.339065] Process swapper (pid: 0, ti=c0652000 task=c05fe500
task.ti=c0652000)
[ 84.346244] Stack: c05fea4c c05fea38 c0653ee8 00000046 efd2e7d2
00000002 00000001 c05fea38
[ 84.354549] c04cbba0 c05fea38 c0653f04 c05fe500 00000286
c05fea38 c0653f04 c0155d09
[ 84.362854] c05fe500 c0653f18 c01565b9 00000000 c0649d80
c0649dac c0653f54 c04bf693
[ 84.371159] Call Trace:
[ 84.373754] [<c010655a>] show_trace_log_lvl+0x1a/0x30
[ 84.378858] [<c010661e>] show_stack_log_lvl+0xae/0xe0
[ 84.383962] [<c0106714>] show_registers+0xc4/0x1f0
[ 84.388807] [<c010695b>] die+0x11b/0x230
[ 84.392787] [<c0106b03>] do_trap+0x93/0xe0
[ 84.396940] [<c0106e38>] do_invalid_op+0x88/0xa0
[ 84.401611] [<c04c1ef2>] error_code+0x72/0x78
[ 84.406023] [<c0155d09>] __rt_mutex_adjust_prio+0x19/0x20
[ 84.411472] [<c01565b9>] rt_mutex_adjust_prio+0x29/0x50
[ 84.416750] [<c04bf693>] rt_read_slowunlock+0x123/0x4a0
[ 84.422027] [<c0156fb6>] rt_rwlock_read_unlock+0x26/0xb0
[ 84.427390] [<c04c0bdd>] rt_read_unlock+0x1d/0x20
[ 84.432423] [<c02cef81>] ABBCCA_rlock+0x71/0x80
[ 84.437008] [<c02cda47>] dotest+0x27/0x400
[ 84.441160] [<c02cf9c3>] locking_selftest+0x1e3/0x8a0
[ 84.446265] [<c0658b0d>] start_kernel+0x25d/0x3b0
[ 84.451023] [<00000000>] 0x0
[ 84.453964] =======================
[ 84.457511] INFO: lockdep is turned off.
[ 84.461403] Code: c0 c7 44 24 08 6d 11 00 00 c7 44 24 04 aa 95 58
c0 c7 04 24 d0 1b 58 c0 e8 1e 3c 00 00 e8 a9 be fd f
f e9 1f ff ff ff 8d 74 26 00 <0f> 0b eb fe c7 44 24 0c 08 be 4c c0 c7
44 24 08 6c 11 00 00 c7
[ 84.480176] EIP: [<c012b900>] task_setprio+0x190/0x1c0 SS:ESP 0068:c0653ec0
[ 84.487105] ---[ end trace ca143223eefdc828 ]---
[ 84.491683] Kernel panic - not syncing: Attempted to kill the idle task!
[ 84.498344] Pid: 0, comm: swapper Tainted: G D 2.6.24.7-rt27 #11
[ 84.504745] [<c010655a>] show_trace_log_lvl+0x1a/0x30
[ 84.509849] [<c0106ff2>] show_trace+0x12/0x20
[ 84.514261] [<c010780c>] dump_stack+0x6c/0x80
[ 84.518673] [<c012e831>] panic+0x51/0x110
[ 84.522739] [<c01324c0>] do_exit+0x650/0x820
[ 84.527065] [<c0106a6d>] die+0x22d/0x230
[ 84.531043] [<c0106b03>] do_trap+0x93/0xe0
[ 84.535196] [<c0106e38>] do_invalid_op+0x88/0xa0
[ 84.539867] [<c04c1ef2>] error_code+0x72/0x78
[ 84.544280] [<c0155d09>] __rt_mutex_adjust_prio+0x19/0x20
[ 84.549730] [<c01565b9>] rt_mutex_adjust_prio+0x29/0x50
[ 84.555006] [<c04bf693>] rt_read_slowunlock+0x123/0x4a0
[ 84.560283] [<c0156fb6>] rt_rwlock_read_unlock+0x26/0xb0
[ 84.565648] [<c04c0bdd>] rt_read_unlock+0x1d/0x20
[ 84.570406] [<c02cef81>] ABBCCA_rlock+0x71/0x80
[ 84.574991] [<c02cda47>] dotest+0x27/0x400
[ 84.579144] [<c02cf9c3>] locking_selftest+0x1e3/0x8a0
[ 84.584247] [<c0658b0d>] start_kernel+0x25d/0x3b0
[ 84.589005] [<00000000>] 0x0
[ 84.591946] =======================
On Fri, 3 Apr 2009, Remy Bohmer wrote:
> Hello Thomas,
>
> 2009/4/3 Remy Bohmer <[email protected]>:
> > Hello Thomas,
> >
> >>> Does anybody recognise these backtraces? And if so, is there a fix for
> >>> it already?
> >>
> >> http://www.kernel.org/pub/linux/kernel/projects/rt/patch-2.6.24.7-rt27.bz2
>
> I integrated -rt27, but this one fails on the locking api-selftests.
> Is this a bug in the selftest? Or is there a real locking bug behind
> it?
Don't think so. The rw locks fixups which we did between -rt20 and
-rt27 might have screwed the lockdep selftests where we create
deadlock situations. What happens if you disable the self tests ?
Thanks,
tglx
Hello Thomas,
>> I integrated -rt27, but this one fails on the locking api-selftests.
>> Is this a bug in the selftest? Or is there a real locking bug behind
>> it?
>
> Don't think so. The rw locks fixups which we did between -rt20 and
> -rt27 might have screwed the lockdep selftests where we create
> deadlock situations.
This is what I hoped for ;-) (A bug in the testtooling...)
> What happens if you disable the self tests ?
The system boots and seems to run properly. We did not yet test for a
longer period of time, but the first looks are that the hangups we had
are gone now. But it would be good for the peace of mind if the
locking-selftest was working properly.
Thanks.
Kind Regards,
Remy
On Sun, 5 Apr 2009, Remy Bohmer wrote:
> > What happens if you disable the self tests ?
>
> The system boots and seems to run properly. We did not yet test for a
> longer period of time, but the first looks are that the hangups we had
> are gone now. But it would be good for the peace of mind if the
> locking-selftest was working properly.
Patches are welcome. :)
Seriously, I'm not going to look into that as my limited capacity is
focussed on 2.6.29-rt.
Thanks,
tglx
Hello Thomas,
2009/4/5 Thomas Gleixner <[email protected]>:
> On Sun, 5 Apr 2009, Remy Bohmer wrote:
>> > What happens if you disable the self tests ?
>>
>> The system boots and seems to run properly. We did not yet test for a
>> longer period of time, but the first looks are that the hangups we had
>> are gone now. But it would be good for the peace of mind if the
>> locking-selftest was working properly.
>
> Patches are welcome. :)
>
> Seriously, I'm not going to look into that as my limited capacity is
> focussed on 2.6.29-rt.
As it should be... :-)
I was not asking you to fix it, my apologies if you read it that way.
It is not that important to me, just a nice-to-have.
Kind Regards,
Remy
On Sun, 5 Apr 2009, Remy Bohmer wrote:
> > Seriously, I'm not going to look into that as my limited capacity is
> > focussed on 2.6.29-rt.
>
> As it should be... :-)
> I was not asking you to fix it, my apologies if you read it that way.
> It is not that important to me, just a nice-to-have.
I did not interpret it that way :) I just wanted to explain instead of
just shrugging you off.
Thanks,
tglx