On Mon, May 24, 2021 at 7:13 PM Andi Kleen <ak@xxxxxxxxxxxxxxx> wrote:
Please let's not start this patch off with dubious claims of safety...to explicitly error out a wbinvd use case before data is alteredI don't see any point of all of this. We really just want to be the same
and wbinvd is needed.
as KVM. Not get into the business of patching a bazillion sub systems
that cannot be used in TDX anyways.
afforded by IgnorePAT. Instead make the true argument that wbinvd is
known to be problematic in guests
and for that reason many bare metal
use cases that require wbinvd have not been ported to guests (like
PMEM unlock), and others that only use wbinvd to opportunistically
enforce a cache state (like ACPI sleep states)
do not see ill effects
from missing wbinvd. Given KVM ships with a policy to elide wbinvd in
many scenarios adopt the same policy for TDX guests.