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Message-ID: <a8e1da0804280026s510deacfq268da0f0fc62a298@mail.gmail.com>
Date: Mon, 28 Apr 2008 15:26:31 +0800
From: "Dave Young" <hidave.darkstar@gmail.com>
To: dpn@isomerica.net
Subject: Re: NULL dereference OOPS on SysRq-w
Cc: "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>, mingo@elte.hu
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On Mon, Apr 28, 2008 at 3:08 PM, Dave Young <hidave.darkstar@gmail.com> wrote:
> On Mon, Apr 28, 2008 at 3:01 PM, Dan Noe <dpn@isomerica.net> wrote:
>  > Dave Young wrote:
>  >
>  > > [snip]
>  > >
>  > > I have a fix for the NULL pointer reference BUG, tested on my pc.
>  > > ---
>  > >
>  > > "m" will be NULL if seq_printf & seq_puts is called from sched_debug_show
>  > > Use SEQ_* macros to fix it
>  > > Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
>  > >
>  >
>  >  There is actually already a patch out for this which simply hasn't made it
>  > upstream yet - Mike Galbraith emailed me with it and it indeed fixes the
>  > problem.  I hadn't realized his email didn't go to lkml.. otherwise I would
>  > have echoed that here to avoid wasting people's time.  My apologies.
>
>  Ok, thanks.
>
>  While debuging this issue I found another BUG about sysrq,
>
>  echo w >/proc/sys/kernel/sysrq
>  My system hangs, there's no response from then on.

Strange, the bug can not be reproduced now. Now I only get the
expected result "Invalid argument".