[PATCH 6/9] KVM: x86: movnti minimum op size of 32-bit is not kept

From: Nadav Amit
Date: Mon Jun 02 2014 - 11:34:44 EST


If the operand-size prefix (0x66) is used in 64-bit mode, the emulator would
assume the destination operand is 64-bit, when it should be 32-bit.

Reminder: movnti does not support 16-bit operands and its default operand size
is 32-bit.

Signed-off-by: Nadav Amit <namit@xxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/emulate.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 4cb0da6..be3f764 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -4836,8 +4836,8 @@ twobyte_insn:
break;
case 0xc3: /* movnti */
ctxt->dst.bytes = ctxt->op_bytes;
- ctxt->dst.val = (ctxt->op_bytes == 4) ? (u32) ctxt->src.val :
- (u64) ctxt->src.val;
+ ctxt->dst.val = (ctxt->op_bytes == 8) ? (u64) ctxt->src.val :
+ (u32) ctxt->src.val;
break;
default:
goto cannot_emulate;
--
1.9.1

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