KVM: x86: CMOV emulation on legacy mode is wrong

On legacy mode CMOV emulation should still clear bits [63:32] even if the
assignment is not done. The previous fix 140bad89fd ("KVM: x86: emulation of
dword cmov on long-mode should clear [63:32]") was incomplete.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Message-Id: <1427719163-5429-2-git-send-email-namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index c941abe800ef5730ebc85ce9998a5092925b6bbf..62f7a395717d1378b43114177043c605afa5ecb2 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -5126,8 +5126,7 @@ twobyte_insn:
        case 0x40 ... 0x4f:     /* cmov */
                if (test_cc(ctxt->b, ctxt->eflags))
                        ctxt->dst.val = ctxt->src.val;
-               else if (ctxt->mode != X86EMUL_MODE_PROT64 ||
-                        ctxt->op_bytes != 4)
+               else if (ctxt->op_bytes != 4)
                        ctxt->dst.type = OP_NONE; /* no writeback */
                break;
        case 0x80 ... 0x8f: /* jnz rel, etc*/