Re: [PATCH v3 09/22] KVM: Do processor compatibility check on resume

From: Isaku Yamahata
Date: Thu Sep 08 2022 - 14:21:30 EST


On Mon, Sep 05, 2022 at 05:27:12PM +0800,
Yuan Yao <yuan.yao@xxxxxxxxxxxxxxx> wrote:

> On Mon, Sep 05, 2022 at 04:40:14PM +0800, Yuan Yao wrote:
> > On Thu, Sep 01, 2022 at 07:17:44PM -0700, isaku.yamahata@xxxxxxxxx wrote:
> > > From: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> > >
> > > So far the processor compatibility check is not done on resume. It should
> > > be done.
> >
> > The resume happens for resuming from S3/S4, so the compatibility
> > checking is used to detecte CPU replacement, or resume from S4 on an
> > different machine ?
>
> By did experiments, I found the resume is called once on CPU 0 before
> other CPUs come UP, so yes it's necessary to check it.

I've added the commit message.

KVM: Do processor compatibility check on resume

So far the processor compatibility check is not done on resume. It should
be done. The resume is called for resuming from S3/S4. CPUs can be
replaced or the kernel can resume from S4 on a different machine. So
compatibility check is desirable.

--
Isaku Yamahata <isaku.yamahata@xxxxxxxxx>