[v2,7/8] Fix emulate_sys[call, enter, exit]()'s fault handling

Commit Message

Takuya Yoshikawa Feb. 10, 2010, 2:13 a.m. UTC

None

Patch

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index a4e44ca..ddec1c5 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1512,7 +1512,7 @@  emulate_syscall(struct x86_emulate_ctxt *ctxt)
 	/* syscall is not available in real mode */
 	if (c->lock_prefix || ctxt->mode == X86EMUL_MODE_REAL
 	    || !is_protmode(ctxt->vcpu))
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
 
@@ -1549,7 +1549,7 @@  emulate_syscall(struct x86_emulate_ctxt *ctxt)
 		ctxt->eflags &= ~(EFLG_VM | EFLG_IF | EFLG_RF);
 	}
 
-	return 0;
+	return X86EMUL_CONTINUE;
 }
 
 static int
@@ -1561,19 +1561,19 @@  emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 
 	/* inject #UD if LOCK prefix is used */
 	if (c->lock_prefix)
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 
 	/* inject #GP if in real mode or paging is disabled */
 	if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) {
 		kvm_inject_gp(ctxt->vcpu, 0);
-		return -1;
+		return X86EMUL_PROPAGATE_FAULT;
 	}
 
 	/* XXX sysenter/sysexit have not been tested in 64bit mode.
 	* Therefore, we inject an #UD.
 	*/
 	if (ctxt->mode == X86EMUL_MODE_PROT64)
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
 
@@ -1582,13 +1582,13 @@  emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 	case X86EMUL_MODE_PROT32:
 		if ((msr_data & 0xfffc) == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		break;
 	case X86EMUL_MODE_PROT64:
 		if (msr_data == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		break;
 	}
@@ -1613,7 +1613,7 @@  emulate_sysenter(struct x86_emulate_ctxt *ctxt)
 	kvm_x86_ops->get_msr(ctxt->vcpu, MSR_IA32_SYSENTER_ESP, &msr_data);
 	c->regs[VCPU_REGS_RSP] = msr_data;
 
-	return 0;
+	return X86EMUL_CONTINUE;
 }
 
 static int
@@ -1626,18 +1626,18 @@  emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 
 	/* inject #UD if LOCK prefix is used */
 	if (c->lock_prefix)
-		return -1;
+		return X86EMUL_UNHANDLEABLE;
 
 	/* inject #GP if in real mode or paging is disabled */
 	if (ctxt->mode == X86EMUL_MODE_REAL || !is_protmode(ctxt->vcpu)) {
 		kvm_inject_gp(ctxt->vcpu, 0);
-		return -1;
+		return X86EMUL_PROPAGATE_FAULT;
 	}
 
 	/* sysexit must be called from CPL 0 */
 	if (kvm_x86_ops->get_cpl(ctxt->vcpu) != 0) {
 		kvm_inject_gp(ctxt->vcpu, 0);
-		return -1;
+		return X86EMUL_PROPAGATE_FAULT;
 	}
 
 	setup_syscalls_segments(ctxt, &cs, &ss);
@@ -1655,7 +1655,7 @@  emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 		cs.selector = (u16)(msr_data + 16);
 		if ((msr_data & 0xfffc) == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		ss.selector = (u16)(msr_data + 24);
 		break;
@@ -1663,7 +1663,7 @@  emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 		cs.selector = (u16)(msr_data + 32);
 		if (msr_data == 0x0) {
 			kvm_inject_gp(ctxt->vcpu, 0);
-			return -1;
+			return X86EMUL_PROPAGATE_FAULT;
 		}
 		ss.selector = cs.selector + 8;
 		cs.db = 0;
@@ -1679,7 +1679,7 @@  emulate_sysexit(struct x86_emulate_ctxt *ctxt)
 	c->eip = ctxt->vcpu->arch.regs[VCPU_REGS_RDX];
 	c->regs[VCPU_REGS_RSP] = ctxt->vcpu->arch.regs[VCPU_REGS_RCX];
 
-	return 0;
+	return X86EMUL_CONTINUE;
 }
 
 int
@@ -2318,8 +2318,9 @@  twobyte_insn:
 		}
 		break;
 	case 0x05: 		/* syscall */
-		if (emulate_syscall(ctxt) == -1)
-			goto cannot_emulate;
+		rc = emulate_syscall(ctxt);
+		if (rc != X86EMUL_CONTINUE)
+			goto done;
 		else
 			goto writeback;
 		break;
@@ -2387,14 +2388,16 @@  twobyte_insn:
 		c->dst.type = OP_NONE;
 		break;
 	case 0x34:		/* sysenter */
-		if (emulate_sysenter(ctxt) == -1)
-			goto cannot_emulate;
+		rc = emulate_sysenter(ctxt);
+		if (rc != X86EMUL_CONTINUE)
+			goto done;
 		else
 			goto writeback;
 		break;
 	case 0x35:		/* sysexit */
-		if (emulate_sysexit(ctxt) == -1)
-			goto cannot_emulate;
+		rc = emulate_sysexit(ctxt);
+		if (rc != X86EMUL_CONTINUE)
+			goto done;
 		else
 			goto writeback;
 		break;