KVM: x86 emulator: add JrCXZ instruction emulation

Add JrCXZ instruction emulation (opcode 0xe3)
Used by FreeBSD boot loader.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index aece501..312e798 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2487,7 +2487,7 @@ static struct opcode opcode_table[256] = {
        /* 0xD8 - 0xDF */
        N, N, N, N, N, N, N, N,
        /* 0xE0 - 0xE7 */
-       X3(D(SrcImmByte)), N,
+       X4(D(SrcImmByte)),
        D(ByteOp | SrcImmUByte | DstAcc), D(SrcImmUByte | DstAcc),
        D(ByteOp | SrcAcc | DstImmUByte), D(SrcAcc | DstImmUByte),
        /* 0xE8 - 0xEF */
@@ -3285,6 +3285,10 @@ special_insn:
                    (c->b == 0xe2 || test_cc(c->b ^ 0x5, ctxt->eflags)))
                        jmp_rel(c, c->src.val);
                break;
+       case 0xe3:      /* jcxz/jecxz/jrcxz */
+               if (address_mask(c, c->regs[VCPU_REGS_RCX]) == 0)
+                       jmp_rel(c, c->src.val);
+               break;
        case 0xe4:      /* inb */
        case 0xe5:      /* in */
                goto do_io_in;