CVE-2017-5753
CVE-2017-5715

Set/restore the guests IBRS value on VM entry. On VM exit back to the
kernel save the guest IBRS value and then set IBRS to 1.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
(backported from commit ae47b6df435ae255747a9aa1a5520bd9ef01005f)
Signed-off-by: Andy Whitcroft <apw@canonical.com>