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Date: Mon, 10 Aug 2009 20:56:18 +0200
Message-ID: <19f34abd0908101156x2bc92b22ud1748abb153800fb@mail.gmail.com>
Subject: Re: kmemcheck in linux-next causes NULL pointer dereference at 
	task_rq_lock
From: Vegard Nossum <vegard.nossum@gmail.com>
To: Eric Paris <eparis@redhat.com>
Cc: linux-kernel@vger.kernel.org, penberg@cs.helsinki.fi, mingo@elte.hu
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2009/8/10 Eric Paris <eparis@redhat.com>:
> I'm using 2.6.31-rc5-next-20090810 on a vmware server.  Originally I saw
> messages about setting to one cpu, so I booted with maxcpu=1.  I get
> this same panic with and without maxpu.  Booting with kmemcheck=0 boots
> just fine.
>
> I have not tested kmemcheck in linus' tree but will start looking for a
> working version now.  Any suggestions or things I should try?

Hi, thanks for the report, and for trying it out.

Does it crash with "kmemcheck=0 maxcpus=1" (it should be maxcpus, not
maxcpu). This should be a simple way of determining whether it was
kmemcheck or the existing maxcpus code, which we use, that broke.

If you can send config (off-list, probably), I will try to reproduce
and investigate more tomorrow.

Thanks,


Vegard