Subject: Re: [PATCH v2 0/4] implement vcpu preempted check

From: Peter Zijlstra <[email-masked]>
Date: Thu, 7 Jul 2016 13:08:01 +0200

On Thu, Jul 07, 2016 at 06:12:51PM +0800, Wanpeng Li wrote:

> Btw, do this in preemption
> notifier means that the vCPU is real preempted on host, however,
> depends on vmexit is different semantic I think.

Not sure; suppose the vcpu is about to reenter, eg, we're in
vcpu_enter_guest() but before the preempt_disable() and the thread gets
preempted. Are we then not preempted? The vcpu might still very much be
in running state but had to service an vmexit due to an MSR or IO port
or whatnot.