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>]

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.

Regards,
Michal

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