From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: kvm: qemu: stop/start cpus before/after devices
Date: Wed, 25 Mar 2009 11:39:32 -0300
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Cc: kvm-devel <kvm@vger.kernel.org>, Dor Laor <dlaor@redhat.com>,
	Yaniv Kamay <yaniv@redhat.com>
To: Avi Kivity <avi@redhat.com>
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On Wed, Mar 25, 2009 at 11:26:19AM -0300, Marcelo Tosatti wrote:
> On Wed, Mar 25, 2009 at 01:45:52PM +0200, Avi Kivity wrote:
> > Marcelo Tosatti wrote:
> >> From: Yaniv Kamay <yaniv@qumranet.com>
> >>
> >> Stop cpus before devices when stopping the VM, start cpus after devices
> >> when starting VM.
> >>
> >>   
> >
> > Why is this needed?
> 
> A vcpu could access a stopped device otherwise. 

Actually on vm_stop its safe because the order happens to be correct,
but on vm_start its the other way around (vcpus start first, and they
should be started last).