Commit 3b32004a authored Jun 02, 2014 by Nadav Amit Committed by Paolo Bonzini Jun 18, 2014

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@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 37c564f2

arch/x86/kvm/emulate.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -4836,8 +4836,8 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
		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;