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Date: Mon, 18 Feb 2008 08:52:29 -0800
From: Arjan van de Ven <arjan@infradead.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>,
       Christoph Lameter <clameter@sgi.com>,
       LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>
Subject: Re: NULL pointer in kmem_cache_alloc with 2.6.25-rc1
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On Mon, 18 Feb 2008 04:59:18 -0800
Andrew Morton <akpm@linux-foundation.org> wrote:

> On Fri, 15 Feb 2008 14:47:01 +0800 "Zhang, Yanmin"
> <yanmin_zhang@linux.intel.com> wrote:
> 
> > Call Trace:
> >  [<ffffffff805e0024>] ? __alloc_skb+0x31/0x121
> >  [<ffffffff805dc389>] ? sock_alloc_send_skb+0x77/0x1d2
> >  [<ffffffff80243897>] ? autoremove_wake_function+0x0/0x2e
> >  [<ffffffff805e12d5>] ? memcpy_fromiovec+0x36/0x66
> >  [<ffffffff80636ec0>] ? unix_stream_sendmsg+0x165/0x333
> >  [<ffffffff805d9863>] ? sock_aio_write+0xd1/0xe0
> >  [<ffffffff80227834>] ? __wake_up_common+0x41/0x74
> >  [<ffffffff8027d267>] ? do_sync_write+0xc9/0x10c
> >  [<ffffffff80265fbb>] ? __do_fault+0x382/0x3cd
> >  [<ffffffff80243897>] ? autoremove_wake_function+0x0/0x2e
> >  [<ffffffff80268840>] ? handle_mm_fault+0x38a/0x70d
> >  [<ffffffff806afd39>] ? error_exit+0x0/0x51
> >  [<ffffffff80228008>] ? __dequeue_entity+0x1c/0x32
> >  [<ffffffff8027d9bb>] ? vfs_write+0xc0/0x136
> >  [<ffffffff8027dee5>] ? sys_write+0x45/0x6e
> >  [<ffffffff8020bdcb>] ? system_call_after_swapgs+0x7b/0x80
> 
> off-topic, but...  Why are all the backtrace decodes here marked as
> being unreliable?

probably because the stack is a tad confused, so the back tracer doesn't see
even a single good stack frame.

Is CONFIG_FRAME_POINTER on?

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