On Wed, Feb 09, 2022, Paolo Bonzini wrote: > While the guest runs, EFER.LME cannot change unless CR0.PG is clear, and therefore > EFER.NX is the only bit that can affect the MMU role. However, set_efer accepts > a host-initiated change to EFER.LME even with CR0.PG=1. In that case, the > MMU has to be reset. > > Fixes: 11988499e62b ("KVM: x86: Skip EFER vs. guest CPUID checks for host-initiated writes") > Cc: stable@xxxxxxxxxxxxxxx > Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> > --- Ugh, but KVM_SET_SREGS handles this... It's basically KVM's equivalent of VMX putting EFER in the VMCS, but then also allowing EFER in the load/store lists. Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>