Re: [PATCH] KVM: X86: Allow userspace to define the microcode version
From: Borislav Petkov
Date: Mon Feb 26 2018 - 06:17:02 EST
On Mon, Feb 26, 2018 at 07:02:29PM +0800, Wanpeng Li wrote:
> > So a guest will have *two* microcode revisions - both of which are most
> > likely wrong?!
>
> Just one revision.
So what does "the non-sensical value which is written by the guest will
not reflect to guest-visible microcode revision" even mean then?
cat /proc/cpuinfo
in the guest shows what exactly?
And what would RDMSR 0x8b show then?
> https://lkml.org/lkml/2017/12/9/29 The original discussion explain in
> more details.
My argument stands: exposing microcode revisions to guests is the wrong
approach. Instead, the kernel should not look at microcode revisions if
it runs virtualized.
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.