2006-08-12 19:39:46

by Steve French

[permalink] [raw]
Subject: oops in close when exiting fsx

ctl-c exiting fsx after a few hours with 2.6.18-rc4 got the following
oops - anyone recognize it?
Although I didn't see cifs symbols on the call stack it is running on a
cifs mount, but it is not
one I have seen before.

BUG: unable to handle kernel NULL pointer dereference at virtual address
0000000 0
printing eip:
c133064f
*pde = 00000000
Oops: 0002 [#1]
Modules linked in: cifs nfsd exportfs lockd nfs_acl ipv6 sunrpc
snd_pcm_oss snd_ mixer_oss snd_seq snd_seq_device af_packet edd ibm_acpi
snd_intel8x0 snd_ac97_co dec snd_ac97_bus snd_pcm snd_timer snd
soundcore snd_page_alloc
CPU: 0
EIP: 0060:[<c133064f>] Not tainted VLI
EFLAGS: 00210002 (2.6.18-rc4-default #1)
EIP is at __down+0x56/0xc5
eax: f7708b6c ebx: f7708b64 ecx: 00000000 edx: f5f77f04
esi: f5f5e030 edi: 00200246 ebp: 00000000 esp: f5f77ed8
ds: 007b es: 007b ss: 0068
Process fsx-linux (pid: 4038, ti=f5f76000 task=f5f5e030 task.ti=f5f76000)
Stack: 00000000 00000000 00000000 00000000 00000000 f76e24a0 00000000
c1038908
00000001 f5f5e030 c1013678 f7708b6c 00000000 f7708b40 f609f600
f7708b64
c132ed37 dff49a40 f5f76000 fa2da685 f611f8c0 f5a5406c 03240e72
00000008
Call Trace:
[<c1038908>] mempool_free+0x43/0x46
[<c1013678>] default_wake_function+0x0/0xc
[<c132ed37>] __down_failed+0x7/0xc
[<fa2da685>] .text.lock.file+0x87/0x9a [cifs]
[<c104e807>] __fput+0xab/0x148
[<c104c453>] filp_close+0x4e/0x54
[<c101773a>] put_files_struct+0x64/0xa6
[<c1018581>] do_exit+0x1c7/0x675
[<c10052b0>] do_syscall_trace+0x12b/0x172
[<c1018a8b>] sys_exit_group+0x0/0xd
[<c1002abf>] syscall_call+0x7/0xb
Code: 89 74 24 24 c7 44 24 28 78 36 01 c1 c7 06 02 00 00 00 9c 5f fa 83
4c 24 20 01 8d 43 08 8b 48 04 8d 54 24 2c 89 50 04 89 44 24 2c <89> 11
ff 43 04 89 4c 24 30 8b 43 04 48 01 03 0f 98 c0 84 c0 75
EIP: [<c133064f>] __down+0x56/0xc5 SS:ESP 0068:f5f77ed8
<3>BUG: sleeping function called from invalid context at kernel/rwsem.c:20
in_atomic():0, irqs_disabled():1
[<c1026618>] down_read+0x12/0x1f
[<c101fcc8>] blocking_notifier_call_chain+0xe/0x29
[<c10183d6>] do_exit+0x1c/0x675
[<c101695e>] printk+0x14/0x18
[<c1003dcd>] die+0x206/0x20e
[<c13315bf>] do_page_fault+0x3ea/0x4b8
[<c13311d5>] do_page_fault+0x0/0x4b8
[<c10035d1>] error_code+0x39/0x40
[<c133064f>] __down+0x56/0xc5
[<c1038908>] mempool_free+0x43/0x46
[<c1013678>] default_wake_function+0x0/0xc
[<c132ed37>] __down_failed+0x7/0xc
[<fa2da685>] .text.lock.file+0x87/0x9a [cifs]
[<c104e807>] __fput+0xab/0x148
[<c104c453>] filp_close+0x4e/0x54
[<c101773a>] put_files_struct+0x64/0xa6
[<c1018581>] do_exit+0x1c7/0x675
[<c10052b0>] do_syscall_trace+0x12b/0x172
[<c1018a8b>] sys_exit_group+0x0/0xd
[<c1002abf>] syscall_call+0x7/0xb
Fixing recursive fault but reboot is needed!


2006-08-13 01:09:39

by Andrew Morton

[permalink] [raw]
Subject: Re: oops in close when exiting fsx

On Sat, 12 Aug 2006 14:40:22 -0500
Steve French <[email protected]> wrote:

> ctl-c exiting fsx after a few hours with 2.6.18-rc4 got the following
> oops - anyone recognize it?
> Although I didn't see cifs symbols on the call stack it is running on a
> cifs mount, but it is not
> one I have seen before.

CIFS is in the trace.

> BUG: unable to handle kernel NULL pointer dereference at virtual address
> 0000000 0
> printing eip:
> c133064f
> *pde = 00000000
> Oops: 0002 [#1]
> Modules linked in: cifs nfsd exportfs lockd nfs_acl ipv6 sunrpc
> snd_pcm_oss snd_ mixer_oss snd_seq snd_seq_device af_packet edd ibm_acpi
> snd_intel8x0 snd_ac97_co dec snd_ac97_bus snd_pcm snd_timer snd
> soundcore snd_page_alloc
> CPU: 0
> EIP: 0060:[<c133064f>] Not tainted VLI
> EFLAGS: 00210002 (2.6.18-rc4-default #1)
> EIP is at __down+0x56/0xc5
> eax: f7708b6c ebx: f7708b64 ecx: 00000000 edx: f5f77f04
> esi: f5f5e030 edi: 00200246 ebp: 00000000 esp: f5f77ed8
> ds: 007b es: 007b ss: 0068
> Process fsx-linux (pid: 4038, ti=f5f76000 task=f5f5e030 task.ti=f5f76000)
> Stack: 00000000 00000000 00000000 00000000 00000000 f76e24a0 00000000
> c1038908
> 00000001 f5f5e030 c1013678 f7708b6c 00000000 f7708b40 f609f600
> f7708b64
> c132ed37 dff49a40 f5f76000 fa2da685 f611f8c0 f5a5406c 03240e72
> 00000008
> Call Trace:
> [<c1038908>] mempool_free+0x43/0x46
> [<c1013678>] default_wake_function+0x0/0xc
> [<c132ed37>] __down_failed+0x7/0xc
> [<fa2da685>] .text.lock.file+0x87/0x9a [cifs]

That's the out-of-line lock section for fs/cifs/file.c

> [<c104e807>] __fput+0xab/0x148
> [<c104c453>] filp_close+0x4e/0x54
> [<c101773a>] put_files_struct+0x64/0xa6
> [<c1018581>] do_exit+0x1c7/0x675
> [<c10052b0>] do_syscall_trace+0x12b/0x172
> [<c1018a8b>] sys_exit_group+0x0/0xd
> [<c1002abf>] syscall_call+0x7/0xb

I'd say that cifs_close() is doing down() on a corrupted semaphore structure.

2006-08-13 08:58:45

by Chuck Ebbert

[permalink] [raw]
Subject: Re: oops in close when exiting fsx

In-Reply-To: <[email protected]>

On Sat, 12 Aug 2006 14:40:22 -0500, Steve French wrote:

> ctl-c exiting fsx after a few hours with 2.6.18-rc4 got the following
> oops - anyone recognize it?
> Although I didn't see cifs symbols on the call stack it is running on a
> cifs mount, but it is not
> one I have seen before.

> EIP is at __down+0x56/0xc5

1a: 8d 43 08 lea 0x8(%ebx),%eax <= addr of sema wait queue list_head
1d: 8b 48 04 mov 0x4(%eax),%ecx <= list->prev
20: 8d 54 24 2c lea 0x2c(%esp),%edx
24: 89 50 04 mov %edx,0x4(%eax)
27: 89 44 24 2c mov %eax,0x2c(%esp)
0: 89 11 mov %edx,(%ecx) <===== list->prev->next = new

The semaphore's wait queue head is corrupted: 'prev' is 0.

> [<c1038908>] mempool_free+0x43/0x46
> [<c1013678>] default_wake_function+0x0/0xc
> [<c132ed37>] __down_failed+0x7/0xc
> [<fa2da685>] .text.lock.file+0x87/0x9a [cifs] <=====
> [<c104e807>] __fput+0xab/0x148
> [<c104c453>] filp_close+0x4e/0x54
> [<c101773a>] put_files_struct+0x64/0xa6
> [<c1018581>] do_exit+0x1c7/0x675
> [<c10052b0>] do_syscall_trace+0x12b/0x172
> [<c1018a8b>] sys_exit_group+0x0/0xd
> [<c1002abf>] syscall_call+0x7/0xb

It came from a lock section in the cifs code. If you disassemble
.text.lock.file in cifs.o, at offset 0x87 (or shortly after) you
will see a jump back to the code that's trying to get the semaphore.

--
Chuck

2006-08-13 18:43:11

by Steve French

[permalink] [raw]
Subject: Re: oops in close when exiting fsx

Chuck Ebbert wrote:
> In-Reply-To: <[email protected]>
>
> On Sat, 12 Aug 2006 14:40:22 -0500, Steve French wrote:
>
>
>> ctl-c exiting fsx after a few hours with 2.6.18-rc4 got the following
>> oops - anyone recognize it?
>> Although I didn't see cifs symbols on the call stack it is running on a
>> cifs mount, but it is not
>> one I have seen before.
>>
>
>
>> EIP is at __down+0x56/0xc5
>>
>
> 1a: 8d 43 08 lea 0x8(%ebx),%eax <= addr of sema wait queue list_head
> 1d: 8b 48 04 mov 0x4(%eax),%ecx <= list->prev
> 20: 8d 54 24 2c lea 0x2c(%esp),%edx
> 24: 89 50 04 mov %edx,0x4(%eax)
> 27: 89 44 24 2c mov %eax,0x2c(%esp)
> 0: 89 11 mov %edx,(%ecx) <===== list->prev->next = new
>
> The semaphore's wait queue head is corrupted: 'prev' is 0.
>
>
>> [<c1038908>] mempool_free+0x43/0x46
>> [<c1013678>] default_wake_function+0x0/0xc
>> [<c132ed37>] __down_failed+0x7/0xc
>> [<fa2da685>] .text.lock.file+0x87/0x9a [cifs] <=====
>> [<c104e807>] __fput+0xab/0x148
>> [<c104c453>] filp_close+0x4e/0x54
>> [<c101773a>] put_files_struct+0x64/0xa6
>> [<c1018581>] do_exit+0x1c7/0x675
>> [<c10052b0>] do_syscall_trace+0x12b/0x172
>> [<c1018a8b>] sys_exit_group+0x0/0xd
>> [<c1002abf>] syscall_call+0x7/0xb
>>
>
> It came from a lock section in the cifs code. If you disassemble
> .text.lock.file in cifs.o, at offset 0x87 (or shortly after) you
> will see a jump back to the code that's trying to get the semaphore.
>
>


Thanks - This is a part of new cifs code recently added to handle posix
locks (it has not pushed to mainline yet) better

down(&pSMBFile->lock_sem);
list_for_each_entry_safe(li, tmp, &pSMBFile->llist, llist) {
list_del(&li->llist);
kfree(li);
}
up(&pSMBFile->lock_sem);


My guess is that there is a path in which the lock_sem is not
initialized - will trace that.