On 8/3/22 20:21, Sean Christopherson wrote:
I've noticed test_illegal_movbe() does not execute with KVM_FEP.
Just making sure: is it intentional?
It's intentional. FEP isn't needed because KVM emulates MOVBE on #UD when it's
not supported by the host, e.g. to allow migrating to an older host.
GP(EmulateOnUD | ModRM, &three_byte_0f_38_f0),
GP(EmulateOnUD | ModRM, &three_byte_0f_38_f1),
*puts historian hat on*
The original reason was to test Linux using MOVBE even on non-Atom
machines, when MOVBE was only on Atoms. :)
Paolo