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Message-Id: <1401723251-8034-7-git-send-email-namit@cs.technion.ac.il>
Date:	Mon,  2 Jun 2014 18:34:08 +0300
From:	Nadav Amit <namit@...technion.ac.il>
To:	pbonzini@...hat.com
Cc:	gleb@...nel.org, tglx@...utronix.de, mingo@...hat.com,
	hpa@...or.com, x86@...nel.org, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org, Nadav Amit <namit@...technion.ac.il>
Subject: [PATCH 6/9] KVM: x86: movnti minimum op size of 32-bit is not kept

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@...technion.ac.il>
---
 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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