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Subject: Re: [Qemu-devel] [RFC] Next gen kvm api
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: KVM list <kvm@vger.kernel.org>, Rob Earhart <earhart@google.com>, qemu-devel <qemu-devel@nongnu.org>, linux-kernel <linux-kernel@vger.kernel.org>

On 02/07/2012 06:29 PM, Jan Kiszka wrote:
> >>>
> >>
> >> Isn't there another level in between just scheduling and full syscall
> >> return if the user return notifier has some real work to do?
> > 
> > Depends on whether you're scheduling a kthread or a userspace process, no?  If 
>
> Kthreads can't return, of course. User space threads /may/ do so. And
> then there needs to be a differences between host and guest in the
> tracked MSRs. 

Right.  Until we randomize kernel virtual addresses (what happened to
that?) and then there will always be a difference, even if you run the
same kernel in the host and guest.

> I think to recall it's a question of another few hundred
> cycles.

Right.

-- 
error compiling committee.c: too many arguments to function