KVM: x86 emulator: fix cli/sti instruction emulation

If IOPL check fail, the cli/sti emulate GP and then we should skip writeback since the default write OP is OP_REG. Signed-off-by: Wei Yongjun <[email protected]> Signed-off-by: Avi Kivity <[email protected]>
iegor · Aug 2, 2010 · 07cbc6c · 07cbc6c
1 parent b16b2b7
commit 07cbc6c
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
@@ -2979,17 +2979,19 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
 		c->dst.type = OP_NONE;	/* Disable writeback. */
 		break;
 	case 0xfa: /* cli */
-		if (emulator_bad_iopl(ctxt, ops))
+		if (emulator_bad_iopl(ctxt, ops)) {
 			emulate_gp(ctxt, 0);
-		else {
+			goto done;
+		} else {
 			ctxt->eflags &= ~X86_EFLAGS_IF;
 			c->dst.type = OP_NONE;	/* Disable writeback. */
 		}
 		break;
 	case 0xfb: /* sti */
-		if (emulator_bad_iopl(ctxt, ops))
+		if (emulator_bad_iopl(ctxt, ops)) {
 			emulate_gp(ctxt, 0);
-		else {
+			goto done;
+		} else {
 			ctxt->interruptibility = KVM_X86_SHADOW_INT_STI;
 			ctxt->eflags |= X86_EFLAGS_IF;
 			c->dst.type = OP_NONE;	/* Disable writeback. */