From mboxrd@z Thu Jan  1 00:00:00 1970
From: mathieu.desnoyers@polymtl.ca (Mathieu Desnoyers)
Date: Wed, 11 Feb 2009 15:13:49 -0500
Subject: [ltt-dev] [BUG] Linux 2.6.28.4 freezing on a 32-bits x86
	Thinkpad T43p
In-Reply-To: <20090211195038.GC25968@elte.hu>
References: <20090204211106.GA30824@Krystal> <20090204211759.GK22608@elte.hu>
	<20090211193125.GA30975@Krystal> <20090211195038.GC25968@elte.hu>
Message-ID: <20090211201349.GB32122@Krystal>

* Ingo Molnar (mingo at elte.hu) wrote:
> 
> * Mathieu Desnoyers <mathieu.desnoyers at polymtl.ca> wrote:
> 
> > Here is a new backtrace, taken with a huge amount of debugging active, which still 
> > points to an interrupt handler nested over kvm_mmu_pte_write as the culprit. It's 
> > weird that the kvm code gets called on my modest Pentium M laptop, which I think 
> > has no VT-x support at all. I am not running any KVM VMs on this machine. The 
> > problem still happens on 2.6.28.4, and Slub redzones did not identify any memory 
> > corruption. This could be due to kvm_mmu_pte_write which either should not be 
> > called at all, or due to improper interrupt disabling in this function.
> 
> Does latest tip:master fix it? In particular this one:
> 
>   9cf161a: x86/cpa: make sure cpa is safe to call in lazy mmu mode
> 
> fixes a crasher related to KVM and mmu notifiers ...
> 
> 	Ingo

I'll try to apply commit 
9cf161a: x86/cpa: make sure cpa is safe to call in lazy mmu mode

To my 2.6.28.4 kernel to change the configuration minimally and see if
it helps. I guess we'll have to wait a few days before the problem is
reproduced, and even more if it's not. :)

Thanks a lot!

Mathieu

-- 
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68