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Message-ID: <84144f020703140423h2562a353g40c156584943bb7@mail.gmail.com>
Date: Wed, 14 Mar 2007 13:23:02 +0200
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: gregkh@suse.de
Subject: Re: [BUG] Linux 2.6.20.2 - unable to handle kernel paging request - still accessing freed memory
Cc: linux-kernel@vger.kernel.org, "Chris Rankin" <rankincj@yahoo.com>
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Hi Greg,

I think there's some sort of reference counting problem with sysfs in
2.6.20 kernels. Can you please help us debug it further?

On 3/10/07, Chris Rankin <rankincj@yahoo.com> wrote:
> It looks like 2.6.20.2 is still doing Bad Things in /sys.
>
> BUG: unable to handle kernel paging request at virtual address 6b6b6d6b

[snip]

> EIP:    0060:[<c01300ff>]    Not tainted VLI
> EFLAGS: 00010202   (2.6.20.2 #1)
> EIP is at module_put+0x20/0x52
> eax: 6b6b6d6b   ebx: 6b6b6b6b   ecx: 00000001   edx: e7a01000
> esi: edb7e4e4   edi: 6b6b6b6b   ebp: e79fd50c   esp: e7a01f58
> ds: 007b   es: 007b   ss: 0068
> Process udevd (pid: 9656, ti=e7a01000 task=f7a46030 task.ti=e7a01000)
> Stack: eba628a0 c0183a1e 00000010 ed570870 e7a641d0 c0151263 00000000 00000000
>        f7ff2208 ed570870 f745b678 00000000 ed570870 c014eda0 00000003 00000003
>        f745b678 f745b6f8 c014fd99 00000003 00000007 00000003 e7a01000 c0102bde
> Call Trace:
>  [<c0183a1e>] sysfs_release+0x2d/0x4c
>  [<c0151263>] __fput+0x96/0x13c
>  [<c014eda0>] filp_close+0x51/0x58
>  [<c014fd99>] sys_close+0x70/0xa7
>  [<c0102bde>] sysenter_past_esp+0x5f/0x85
>  [<c0270033>] __sched_text_start+0x613/0x971

There's also some previous discussion here:

http://lkml.org/lkml/2007/3/1/114

                                           Pekka