On Thu, Jan 24, 2019 at 9:59 AM Sean Christopherson
<sean.j.christopherson@xxxxxxxxx> wrote:
>
> Per commit c20363006af6 ("KVM: VMX: Let gcc to choose which registers
> to save (x86_64)"), the only reason RDX is saved/loaded to/from the
> stack is because it was specified as an input, i.e. couldn't be marked
> as clobbered (ignoring the fact that "saving" it to a dummy output
> would indirectly mark it as clobbered).
>
> Now that RDX is no longer an input, mark it as clobbered and zero it
> out to prevent speculative use.
>
> Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
