Re: [PATCH] kvm/sev: make SEV/SEV-ES asids configurable

From: José Pekkarinen
Date: Tue Oct 10 2023 - 08:20:11 EST


On 2023-10-10 14:40, Paolo Bonzini wrote:
On 10/10/23 13:35, Greg KH wrote:
On Tue, Oct 10, 2023 at 01:04:39PM +0300, José Pekkarinen wrote:
There are bioses that doesn't allow to configure the
number of asids allocated for SEV/SEV-ES, for those
cases, the default behaviour allocates all the asids
for SEV, leaving no room for SEV-ES to have some fun.

In addition to what Greg pointed out (and there are many more cases
that have to be checked for errors, including possible overflows), why
is it correct to just ignore what's in CPUID?

I'll check if I can use cpuid info to improve this
for v2, I just noticed my cpu advertises sev_es but
the kernel doesn't activate it despite of the kvm_amd
parameter being set, so I tried to fix it this way, but
any comments or ideas for improvement are welcomed.

Thanks!

José.