Re: 2.6.20 BUG: soft lockup detected on CPU#0!

Andrew Morton
2007-02-08T04:48:10Z

On Thu, 8 Feb 2007 00:02:10 +0100 (CET) Lukasz Trabinski <lukasz@wsisiz.edu.pl> wrote:

> Hello
>
> On 2.6.19 I had about 60 days uptime, on 2.6.20 2 days :(
>

Did the machine actually fail? Or did it just print these messages and
keep going?

>
> oceanic:~$ uname -a
> Linux oceanic.wsisiz.edu.pl 2.6.20-oceanic #2 SMP Sun Feb 4 21:55:29 CET
> 2007 x86_64 x86_64 x86_64 GNU/Linux
>
> Feb 7 22:46:00 oceanic kernel: BUG: soft lockup detected on CPU#0!
> Feb 7 22:46:00 oceanic kernel:
> Feb 7 22:46:00 oceanic kernel: Call Trace:
> Feb 7 22:46:00 oceanic kernel: <IRQ> [<ffffffff80250550>] softlockup_tick+0xdb/0xed
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8022ea87>] __do_softirq+0x55/0xc4
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8023256c>] update_process_times+0x42/0x68
> Feb 7 22:46:00 oceanic kernel: [<ffffffff80213e36>] smp_local_timer_interrupt+0x34/0x55
> Feb 7 22:46:00 oceanic kernel: [<ffffffff80214316>] smp_apic_timer_interrupt+0x51/0x68
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8020a3a6>] apic_timer_interrupt+0x66/0x70
> Feb 7 22:46:00 oceanic kernel: <EOI> [<ffffffff804393c3>] _spin_unlock_irqrestore+0x8/0x9
> Feb 7 22:46:00 oceanic kernel: [<ffffffff804393c3>] _spin_unlock_irqrestore+0x8/0x9
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8023dddd>] hrtimer_try_to_cancel+0x4a/0x53
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8023ddf2>] hrtimer_cancel+0xc/0x16
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8023ddf2>] hrtimer_cancel+0xc/0x16
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8022cc66>] do_exit+0x1c8/0x800
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8022d31d>] sys_exit_group+0x0/0xe
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8020995c>] tracesys+0xdc/0xe1
> Feb 7 22:46:00 oceanic kernel:
> Feb 7 22:46:00 oceanic kernel: BUG: soft lockup detected on CPU#1!
> Feb 7 22:46:00 oceanic kernel:
> Feb 7 22:46:00 oceanic kernel: Call Trace:
> Feb 7 22:46:00 oceanic kernel: <IRQ> [<ffffffff80250550>] softlockup_tick+0xdb/0xed
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8023256c>] update_process_times+0x42/0x68
> Feb 7 22:46:00 oceanic kernel: [<ffffffff80213e36>] smp_local_timer_interrupt+0x34/0x55
> Feb 7 22:46:00 oceanic kernel: [<ffffffff80214316>] smp_apic_timer_interrupt+0x51/0x68
> Feb 7 22:46:00 oceanic kernel: [<ffffffff802338c8>] __group_send_sig_info+0x35/0x8b
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8022e0f1>] it_real_fn+0x0/0x4f
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8020a3a6>] apic_timer_interrupt+0x66/0x70
> Feb 7 22:46:00 oceanic kernel: [<ffffffff802164da>] flat_send_IPI_mask+0x0/0x3d
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8023dc52>] hrtimer_run_queues+0x105/0x164
> Feb 7 22:46:00 oceanic kernel: [<ffffffff80231d0f>] run_timer_softirq+0x21/0x19f
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8022eb49>] tasklet_action+0x53/0x9d
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8022ea87>] __do_softirq+0x55/0xc4
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8020a8fc>] call_softirq+0x1c/0x28
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8020c3b1>] do_softirq+0x2c/0x7d
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8021431b>] smp_apic_timer_interrupt+0x56/0x68
> Feb 7 22:46:00 oceanic kernel: [<ffffffff80208a55>] default_idle+0x0/0x3d
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8020a3a6>] apic_timer_interrupt+0x66/0x70
> Feb 7 22:46:00 oceanic kernel: <EOI> [<ffffffff80208a7e>] default_idle+0x29/0x3d
> Feb 7 22:46:00 oceanic kernel: [<ffffffff80208ae4>] cpu_idle+0x52/0x71
> Feb 7 22:46:00 oceanic kernel: [<ffffffff8057fbbc>] start_secondary+0x465/0x474
>

The softlock detector has a long history of false positives and precious
few true positives, in my experience.