[3.10] Oopses in kmem_cache_allocate() via prepare_creds()

[Simon Kirby]

We saw two Oopses overnight on two separate boxes that seem possibly
related, but both are weird. These boxes typically run btrfs for rsync
snapshot backups (and usually Oops in btrfs ;), but not this time!
backup02 was running 3.10-rc6 plus btrfs-next at the time, and backup03
was running 3.10 release plus btrfs-next from yesterday. Full kern.log
and .config at http://0x.ca/sim/ref/3.10/

backup02's first Oops:

BUG: unable to handle kernel paging request at 0000000100000000
IP: [<ffffffff81124beb>] kmem_cache_alloc+0x4b/0x110
PGD 1f54f7067 PUD 0
Oops: 0000 [#1] SMP
Modules linked in: ipmi_devintf ipmi_si ipmi_msghandler aoe microcode serio_raw bnx2 evdev
CPU: 0 PID: 23112 Comm: ionice Not tainted 3.10.0-rc6-hw+ #46
Hardware name: Dell Inc. PowerEdge 2950/0NH278, BIOS 2.7.0 10/30/2010
task: ffff8802c3f08000 ti: ffff8801b4876000 task.ti: ffff8801b4876000
RIP: 0010:[<ffffffff81124beb>]  [<ffffffff81124beb>] kmem_cache_alloc+0x4b/0x110
RSP: 0018:ffff8801b4877e88  EFLAGS: 00010206
RAX: 0000000000000000 RBX: ffff8802c3f08000 RCX: 00000000017f040e
RDX: 00000000017f040d RSI: 00000000000000d0 RDI: ffffffff8107a503
RBP: ffff8801b4877ec8 R08: 0000000000016a80 R09: 0000000000000000
R10: 00007fff025fe120 R11: 0000000000000246 R12: 00000000000000d0
R13: ffff88042d8019c0 R14: 0000000100000000 R15: 00007fc3588ee97f
FS:  0000000000000000(0000) GS:ffff88043fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000100000000 CR3: 0000000409d68000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
 ffff8801b4877ed8 ffffffff8112a1bc ffff8800985acd20 ffff8802c3f08000
 0000000000000001 00007fc3588ee334 00007fc358af5758 00007fc3588ee97f
 ffff8801b4877ee8 ffffffff8107a503 ffff8801b4877ee8 ffffffffffffffea
Call Trace:
 [<ffffffff8112a1bc>] ? __fput+0x12c/0x240
 [<ffffffff8107a503>] prepare_creds+0x23/0x150
 [<ffffffff811272d4>] SyS_faccessat+0x34/0x1f0
 [<ffffffff811274a3>] SyS_access+0x13/0x20
 [<ffffffff8179e7a9>] system_call_fastpath+0x16/0x1b
Code: 75 f0 4c 89 7d f8 49 8b 4d 00 65 48 03 0c 25 68 da 00 00 48 8b 51 08 4c 8b 31 4d 85 f6 74 5f 49 63 45 20 4d 8b 45 00 48 8d 4a 01 <49> 8b 1c 06 4c 89 f0 65 49 0f c7 08 0f 94 c0 84 c0 74 c8 49 63
RIP  [<ffffffff81124beb>] kmem_cache_alloc+0x4b/0x110
 RSP <ffff8801b4877e88>
CR2: 0000000100000000
---[ end trace 744477356cd98306 ]---

backup03's first Oops:

BUG: unable to handle kernel paging request at ffff880502efc240
IP: [<ffffffff81124c4b>] kmem_cache_alloc+0x4b/0x110
PGD 1d3a067 PUD 0
Oops: 0000 [#1] SMP
Modules linked in: aoe ipmi_devintf ipmi_msghandler bnx2 microcode serio_raw evdev
CPU: 6 PID: 14066 Comm: perl Not tainted 3.10.0-hw+ #2
Hardware name: Dell Inc. PowerEdge R510/0DPRKF, BIOS 1.11.0 07/23/2012
task: ffff88040111c3b0 ti: ffff8803c23ae000 task.ti: ffff8803c23ae000
RIP: 0010:[<ffffffff81124c4b>]  [<ffffffff81124c4b>] kmem_cache_alloc+0x4b/0x110
RSP: 0018:ffff8803c23afd90  EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff88040111c3b0 RCX: 000000000002a76e
RDX: 000000000002a76d RSI: 00000000000000d0 RDI: ffffffff8107a4e3
RBP: ffff8803c23afdd0 R08: 0000000000016a80 R09: 00000000ffffffff
R10: fffffffffffffffe R11: ffffffffffffffd0 R12: 00000000000000d0
R13: ffff88041d403980 R14: ffff880502efc240 R15: ffff88010e375a40
FS:  00007f2cae496700(0000) GS:ffff88041f2c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff880502efc240 CR3: 00000001e0ced000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
 ffff8803c23afe98 ffff8803c23afdb8 ffffffff81133811 ffff88040111c3b0
 ffff88010e375a40 0000000001200011 00007f2cae4969d0 ffff88010e375a40
 ffff8803c23afdf0 ffffffff8107a4e3 ffffffff81b49b80 0000000001200011
Call Trace:
 [<ffffffff81133811>] ? final_putname+0x21/0x50
 [<ffffffff8107a4e3>] prepare_creds+0x23/0x150
 [<ffffffff8107ab11>] copy_creds+0x31/0x160
 [<ffffffff8101a97b>] ? unlazy_fpu+0x9b/0xb0
 [<ffffffff8104ef09>] copy_process.part.49+0x239/0x1390
 [<ffffffff81143312>] ? __alloc_fd+0x42/0x100
 [<ffffffff81050134>] do_fork+0xa4/0x320
 [<ffffffff81131b77>] ? __do_pipe_flags+0x77/0xb0
 [<ffffffff81143426>] ? __fd_install+0x26/0x60
 [<ffffffff81050431>] SyS_clone+0x11/0x20
 [<ffffffff817ad849>] stub_clone+0x69/0x90
 [<ffffffff817ad569>] ? system_call_fastpath+0x16/0x1b
Code: 75 f0 4c 89 7d f8 49 8b 4d 00 65 48 03 0c 25 68 da 00 00 48 8b 51 08 4c 8b 31 4d 85 f6 74 5f 49 63 45 20 4d 8b 45 00 48 8d 4a 01 <49> 8b 1c 06 4c 89 f0 65 49 0f c7 08 0f 94 c0 84 c0 74 c8 49 63
RIP  [<ffffffff81124c4b>] kmem_cache_alloc+0x4b/0x110
 RSP <ffff8803c23afd90>
CR2: ffff880502efc240
---[ end trace 956d153150ecc57f ]---

Simon-
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/