Re: 2.6.16 Guest Hangs on Boot

Joerg Roedel
2010-09-16T11:02:49Z

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