KVM: x86 emulator: fix byte-sized MOVZX/MOVSX (361cad2b) · Commits · 戴 / test

Commit removed ByteOp from MOVZX/MOVSX, replacing them by SrcMem8, but neglected to fix the dependency in the emulation code on ByteOp. This caused the instruction not to have any effect in some circumstances. Fix by replacing the check for ByteOp with the equivalent src.op_bytes == 1. Signed-off-by:

Avi Kivity <avi@redhat.com>

arch/x86/kvm/emulate.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -4517,12 +4517,12 @@ twobyte_insn:
		break;
		case 0xb6 ... 0xb7: /* movzx */
		ctxt->dst.bytes = ctxt->op_bytes;
		ctxt->dst.val = (ctxt->d & ByteOp) ? (u8) ctxt->src.val
		ctxt->dst.val = (ctxt->src.bytes == 1) ? (u8) ctxt->src.val
		: (u16) ctxt->src.val;
		break;
		case 0xbe ... 0xbf: /* movsx */
		ctxt->dst.bytes = ctxt->op_bytes;
		ctxt->dst.val = (ctxt->d & ByteOp) ? (s8) ctxt->src.val :
		ctxt->dst.val = (ctxt->src.bytes == 1) ? (s8) ctxt->src.val :
		(s16) ctxt->src.val;
		break;
		case 0xc0 ... 0xc1: /* xadd */

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