From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joerg Roedel <joro@8bytes.org>
Subject: Re: 2.6.16 Guest Hangs on Boot
Date: Thu, 16 Sep 2010 13:02:47 +0200
Message-ID: <20100916110247.GA15338@8bytes.org>
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Cc: Alec Joseph Rivera <eijhei@gmail.com>, kvm@vger.kernel.org,
	Meric Mara <mmara@8layertech.com>,
	Renan Mara <rmara@8layertech.com>
To: Alexander Graf <agraf@suse.de>
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On Thu, Sep 16, 2010 at 12:27:29PM +0200, Alexander Graf wrote:
> Alec Joseph Rivera wrote:
> > Program received signal SIGINT, Interrupt.
> > 0xc015405f in ?? ()
> > (gdb) bt
> > #0  0xc015405f in ?? ()
> >   
> 
> 0xc015405a <__pte_alloc_kernel+82>:    mov    (%edi),%eax
> 0xc015405c <__pte_alloc_kernel+84>:    mov    0x4(%edi),%edx
> 0xc015405f <__pte_alloc_kernel+87>:    lock cmpxchg8b (%edi)
> 0xc0154063 <__pte_alloc_kernel+91>:    jne    0xc015405a
> <__pte_alloc_kernel+82>

This looks like a bug I also have seen recently on 32 bit host-kvm. The
instruction emulation for 'lock cmpxchg8b' was broken so that the rip
was not advanced and the guest just iterated over this instruction again
and again. I thought this was fixed with the latest kvm updates in
2.6.36.

	Joerg