From 660696d1d16a71e15549ce1bf74953be1592bcd3 Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Wed, 24 Apr 2013 13:38:36 +0300
Subject: [PATCH] KVM: X86 emulator: fix source operand decoding for 8bit
mov[zs]x instructions
Source operand for one byte mov[zs]x is decoded incorrectly if it is in
high byte register. Fix that.
Cc: stable@vger.kernel.org
Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
arch/x86/kvm/emulate.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 46f63b8d09f43..8e517bba6a7c9 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -4172,6 +4172,10 @@ static int decode_operand(struct x86_emulate_ctxt *ctxt, struct operand *op,
break;
case OpMem8:
ctxt->memop.bytes = 1;
+ if (ctxt->memop.type == OP_REG) {
+ ctxt->memop.addr.reg = decode_register(ctxt, ctxt->modrm_rm, 1);
+ fetch_register_operand(&ctxt->memop);
+ }
goto mem_common;
case OpMem16:
ctxt->memop.bytes = 2;
--
GitLab