From 82a636bb34b5dce4c6c5f815b6b01e89bc6edd3f Mon Sep 17 00:00:00 2001
From: Marcelo Tosatti <mtosatti@redhat.com>
Date: Wed, 11 Nov 2009 17:29:49 -0200
Subject: [PATCH] --- yaml --- r: 185938 b: refs/heads/master c:
 cb84b55f6cde26c7c17beaf87da08645ae6ccbf9 h: refs/heads/master v: v3

---
 [refs]                   |  2 +-
 trunk/arch/x86/kvm/x86.c | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 670e166bec03..ab46d2c27a31 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 3fd28fce765632d0fe46b31f63c0e7a7ec6c6b79
+refs/heads/master: cb84b55f6cde26c7c17beaf87da08645ae6ccbf9
diff --git a/trunk/arch/x86/kvm/x86.c b/trunk/arch/x86/kvm/x86.c
index 8d860e0301a0..279318677911 100644
--- a/trunk/arch/x86/kvm/x86.c
+++ b/trunk/arch/x86/kvm/x86.c
@@ -4410,6 +4410,15 @@ static int is_vm86_segment(struct kvm_vcpu *vcpu, int seg)
 		(kvm_get_rflags(vcpu) & X86_EFLAGS_VM);
 }
 
+static void kvm_check_segment_descriptor(struct kvm_vcpu *vcpu, int seg,
+					 u16 selector)
+{
+	/* NULL selector is not valid for CS and SS */
+	if (seg == VCPU_SREG_CS || seg == VCPU_SREG_SS)
+		if (!selector)
+			kvm_queue_exception_e(vcpu, TS_VECTOR, selector >> 3);
+}
+
 int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
 				int type_bits, int seg)
 {
@@ -4419,6 +4428,8 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
 		return kvm_load_realmode_segment(vcpu, selector, seg);
 	if (load_segment_descriptor_to_kvm_desct(vcpu, selector, &kvm_seg))
 		return 1;
+
+	kvm_check_segment_descriptor(vcpu, seg, selector);
 	kvm_seg.type |= type_bits;
 
 	if (seg != VCPU_SREG_SS && seg != VCPU_SREG_CS &&