Re: [BUG] Linux 2.6.25-rc2 - Kernel Ooops while running dbench

[Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>]

Pekka Enberg wrote:
> On Sat, 16 Feb 2008 11:14:46 +0530 Kamalesh Babulal
> <kamalesh@linux.vnet.ibm.com> wrote:
>>  > The 2.6.25-rc2 kernel oopses while running dbench on ext3 filesystem
>>  > mounted with mount -o data=writeback,nobh option on the x86_64 box
>>  >
>>  > BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
>>  > IP: [<ffffffff80274972>] kmem_cache_alloc+0x3a/0x6c
>>  > PGD 1f6860067 PUD 1f5d64067 PMD 0
>>  > Oops: 0000 [1] SMP
>>  > CPU 3
>>  > Modules linked in:
>>  > Pid: 4271, comm: dbench Not tainted 2.6.25-rc2-autotest #1
>>  > RIP: 0010:[<ffffffff80274972>]  [<ffffffff80274972>] kmem_cache_alloc+0x3a/0x6c
>>  > RSP: 0000:ffff8101fb041dc8  EFLAGS: 00010246
>>  > RAX: 0000000000000000 RBX: ffff810180033c00 RCX: ffffffff8027b269
>>  > RDX: 0000000000000000 RSI: 00000000000080d0 RDI: ffffffff80632d70
>>  > RBP: 00000000000080d0 R08: 0000000000000001 R09: 0000000000000000
>>  > R10: ffff8101feb36e50 R11: 0000000000000190 R12: 0000000000000001
>>  > R13: 0000000000000000 R14: ffff8101f8f38000 R15: 00000000ffffff9c
>>  > FS:  0000000000000000(0000) GS:ffff8101fff0f000(0063) knlGS:00000000f7e41460
>>  > CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
>>  > CR2: 0000000000000000 CR3: 00000001f5620000 CR4: 00000000000006e0
>>  > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>>  > DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
>>  > Process dbench (pid: 4271, threadinfo ffff8101fb040000, task ffff8101fb180000)
>>  > Stack:  0000000000000001 ffff8101fb041ea8 0000000000000001 ffffffff8027b269
>>  >  ffff8101fb041ea8 ffffffff80281fe8 0000000000000001 0000000000000000
>>  >  ffff8101fb041ea8 00000000ffffff9c 000000000000000b 0000000000000001
>>  > Call Trace:
>>  >  [<ffffffff8027b269>] get_empty_filp+0x55/0xf9
>>  >  [<ffffffff80281fe8>] __path_lookup_intent_open+0x22/0x8f
>>  >  [<ffffffff80282853>] open_namei+0x86/0x5a7
>>  >  [<ffffffff8027d019>] vfs_stat_fd+0x3c/0x4a
>>  >  [<ffffffff80279ab1>] do_filp_open+0x1c/0x3d
>>  >  [<ffffffff80279c2c>] get_unused_fd_flags+0x79/0x111
>>  >  [<ffffffff80279dce>] do_sys_open+0x46/0xca
>>  >  [<ffffffff80221c82>] ia32_sysret+0x0/0xa
> 
> On Mon, Feb 18, 2008 at 2:59 PM, Andrew Morton
> <akpm@linux-foundation.org> wrote:
>>  Looks to me like we broke slab.  Christoph is offline until the 27th..
> 
> This is probably fixed by:
> 
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=00e962c5408b9f2d0bebd2308673fe982cb9a5fe
> 
> As this is on the regression list, Kamalesh, can you please confirm
> it's fixed now?
> 
>                              Pekka

Thanks, I tested the 2.6.25-rc3-git4 kernel and the oops is not reproducible. This commit seems to fix the kernel oops.

-- 
Thanks & Regards,
Kamalesh Babulal,
Linux Technology Center,
IBM, ISTL.