Re: [PROBLEM] 2.6.22-rc2 panics on x86-64 with slub

[Jens Axboe <jens.axboe@oracle.com>]

On Tue, May 22 2007, Hugh Dickins wrote:
> On Tue, 22 May 2007, Srihari Vijayaraghavan wrote:
> > --- Ingo Molnar <mingo@elte.hu> wrote:
> > > * Srihari Vijayaraghavan <sriharivijayaraghavan@yahoo.com.au> wrote:
> > > > Yup, with CONFIG_SMP=n, I'm unable to reproduce the problem. It's 
> > > > quite stable actually (having completed a dozen kernel compile 
> > > > sessions so far).
> > 
> > [...]
> > 
> > > could you enable CONFIG_PROVE_LOCKING - does it spit out any warning 
> > > into the syslog?
> > 
> > Compiled slub with SMP & CONFIG_PROVE_LOCKING. No luck. It still hangs solid
> > after the second spinlock lockup call trace.
> > 
> > Here's the relevant sections of the kernel logs:
> > 
> > ...
> > Freeing unused kernel memory: 228k freed
> > BUG: spinlock bad magic on CPU#1, init/1
> >  lock: ffff81011f5f1100, .magic: ffff8101, .owner: <none>/-1, .owner_cpu: -1
> > 
> > Call Trace:
> >  [<ffffffff802f326a>] _raw_spin_lock+0x22/0xf6
> >  [<ffffffff8026b2d5>] vma_adjust+0x21c/0x446
> >  [<ffffffff8026b2d5>] vma_adjust+0x21c/0x446
> >  [<ffffffff8026b9d4>] vma_merge+0x10c/0x195
> >  [<ffffffff8026c757>] do_mmap_pgoff+0x3f5/0x794
> >  [<ffffffff803fff0c>] _spin_unlock_irq+0x24/0x27
> >  [<ffffffff8020f414>] sys_mmap+0xe5/0x110
> >  [<ffffffff80209dde>] system_call+0x7e/0x83
> > ...
> > PM: Adding info for No Bus:vcsa1
> > BUG: spinlock lockup on CPU#1, hostname/369, ffff81011f5f1fc0
> > 
> > Call Trace:
> >  [<ffffffff802f3317>] _raw_spin_lock+0xcf/0xf6
> >  [<ffffffff8026ec9c>] anon_vma_unlink+0x1c/0x68
> >  [<ffffffff8026ec9c>] anon_vma_unlink+0x1c/0x68
> >  [<ffffffff80269aa0>] free_pgtables+0x69/0xc4
> >  [<ffffffff8026ad0e>] exit_mmap+0x91/0xeb
> >  [<ffffffff80228cea>] mmput+0x2c/0x9f
> >  [<ffffffff8022df72>] do_exit+0x22e/0x82e
> >  [<ffffffff8022e5f4>] sys_exit_group+0x0/0xe
> >  [<ffffffff80209dde>] system_call+0x7e/0x83
> > 
> > 
> > Surprisingly, with CONFIG_SMP=n, CONFIG_PROVE_LOCKING produces this with slub
> > (then hangs solid):
> > 
> > Freeing unused kernel memory: 188k freed
> > BUG: spinlock lockup on CPU#0, init/1, ffff81011e9d3160
> > 
> > Call Trace:
> >  [<ffffffff802eca20>] _raw_spin_lock+0xca/0xe8
> >  [<ffffffff80265d6d>] vma_adjust+0x218/0x442
> >  [<ffffffff80265d6d>] vma_adjust+0x218/0x442
> >  [<ffffffff8026646b>] vma_merge+0x10c/0x195
> >  [<ffffffff802671d5>] do_mmap_pgoff+0x3f5/0x790
> >  [<ffffffff803f6e84>] _spin_unlock_irq+0x24/0x27
> >  [<ffffffff8020ead0>] sys_mmap+0xe5/0x110
> >  [<ffffffff80209cce>] system_call+0x7e/0x83
> > 
> > To recap:
> > 1. No problems with slub on CONFIG_SMP=n & CONFIG_PROVE_LOCKING=n
> > 2. Problem with slub on CONFIG_SMP=n & CONFIG_PROVE_LOCKING=y (perhaps a. some
> > locking issue when slub is activated or b. something is wrong with 'prove
> > locking' mechanism when slub is activated or c. something else I don't see) 
> > 3. Problem with slub on CONFIG_SMP=y (even without CONFIG_PROVE_LOCKING=y)
> 
> You've made no mention of trying the patch I sent yesterday, or better,
> the patch Christoph replied with to replace it.  Please clarify whether
> you're getting the above after applying one of those patches - thanks.

Christophs patch works for me!

-- 
Jens Axboe