Re: 2.6.20-git13 kernel BUG at /mnt/md0/devel/linux-git/kernel/time/tick-sched.c:168

[Michal Piotrowski <michal.k.k.piotrowski@gmail.com>]

Michal Piotrowski napisał(a):
> On 17/02/07, Alex Riesen <fork0@users.sourceforge.net> wrote:
>> Thomas Gleixner, Sat, Feb 17, 2007 16:14:17 +0100:
>> > On Sat, 2007-02-17 at 15:47 +0100, Alex Riesen wrote:
>> > > > > 164             if (need_resched())
>> > > > > 165                     goto end;
>> > > > > 166
>> > > > > 167             cpu = smp_processor_id();
>> > > > > 168             BUG_ON(local_softirq_pending());
>> > > >
>> > > > Hmm, the BUG_ON is inside of an interrupt disabled region, so we
>> should
>> > > > have bailed out early in the need_resched() check above (because
>> we are
>> > > > in the idle task context according to the stack trace).
>> > > >
>> > > > Is this reproducible ?
>> > >
>> > > Seen this too (Ubuntu, P4/ht-SMT, SATA, typed from screen):
>> >
>> > Can you please apply the patch below, so we can at least see, which
>> > softirq is pending. This should trigger independently of hrtimers and
>> > dynticks. You can keep it compiled in and disable it at the kernel
>> > commandline with "nohz=off" and / or "highres=off"
>>
>> It did, only one time:
>>
>> Idle: local softirq pending: 0020<6>USB Universal Host Controller
>> Interface driver v3.0
>>
> 
> sudo cat /var/log/messages | grep Idle
> Feb 17 17:35:34 bitis-gabonica kernel: Idle: local softirq pending:
> 0020<6>hdd: ATAPI 48X DVD-ROM DVD-R CD-R/RW drive, 2048kB Cache,
> UDMA(33)
> Feb 17 19:20:01 bitis-gabonica kernel: Idle: local softirq pending:
> 0020<3>Idle: local softirq pending: 0020<3>Idle: local softirq
> pending: 0020<7>PM: Removing info for No Bus:vcs7
> 
> cat /proc/interrupts
>           CPU0       CPU1
>  0:     232838          0   IO-APIC-edge      timer
>  1:        401          0   IO-APIC-edge      i8042
>  7:          0          0   IO-APIC-edge      parport0
>  8:          1          0   IO-APIC-edge      rtc
>  9:          1          0   IO-APIC-fasteoi   acpi
>  12:          4          0   IO-APIC-edge      i8042
>  14:        319          0   IO-APIC-edge      ide0
>  15:       1612          0   IO-APIC-edge      ide1
>  16:      16494          0   IO-APIC-fasteoi   uhci_hcd:usb3, libata
>  17:       4670          0   IO-APIC-fasteoi   uhci_hcd:usb1, uhci_hcd:usb4
>  18:          0          0   IO-APIC-fasteoi   uhci_hcd:usb2
>  19:          2          0   IO-APIC-fasteoi   ehci_hcd:usb5
>  20:       2822          0   IO-APIC-fasteoi   Intel ICH5
>  21:       2881          0   IO-APIC-fasteoi   eth1
>  22:         58          0   IO-APIC-fasteoi   eth0
> NMI:          0          0
> LOC:     232562     232846
> ERR:          0
> MIS:          0
> 
> I can confirm that this is ICH5 SATA controller problem.

Here is something interesting

cat /var/log/messages | tail -n 300 | grep NOHZ
Feb 20 20:09:39 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 20 20:09:39 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 20 21:10:01 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 20 23:20:01 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:10:28 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:10:46 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
								^^^^^^^^^

Feb 21 05:10:57 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:11:48 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:12:02 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:12:02 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:12:23 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:12:29 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:13:27 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:13:49 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:13:54 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:14:48 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:15:11 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:15:13 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:15:16 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:16:18 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:16:31 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:17:03 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:17:06 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:17:09 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:17:12 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
Feb 21 05:17:17 bitis-gabonica kernel: NOHZ: local_softirq_pending 20
Feb 21 05:17:18 bitis-gabonica kernel: NOHZ: local_softirq_pending 02
       ^^^^^^^^
23 times in 7 minutes.


Regards,
Michal

--
Michal K. K. Piotrowski
LTG - Linux Testers Group (PL)
(http://www.stardust.webpages.pl/ltg/)
LTG - Linux Testers Group (EN)
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