From eec10867d11c9c8dfd499933a21d322854b9b69a Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Sun, 24 May 2009 22:19:00 +0300
Subject: [PATCH] --- yaml --- r: 145247 b: refs/heads/master c:
 a2edf57f510cce6a389cc14e58c6ad0a4296d6f9 h: refs/heads/master i:   145245:
 0af59981440bacfa5f8a6b0bf5fccd08b3bccf58   145243:
 ca285c34de49822df746d09b1a5f634ab02a410c   145239:
 1df1948fa71fa4691755ed9dd318ff9359ed3316   145231:
 8c9ad3dc69eb9f831b5756401871405d5d403d79   145215:
 8353fa91ed88663ccc5f36d13518bf07c1b77bcc v: v3

---
 [refs]                   | 2 +-
 trunk/arch/x86/kvm/x86.c | 6 +++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 204d6fb36526..c048bb886ae9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a8cd0244e9cebcf9b358d24c7e7410062f3665cb
+refs/heads/master: a2edf57f510cce6a389cc14e58c6ad0a4296d6f9
diff --git a/trunk/arch/x86/kvm/x86.c b/trunk/arch/x86/kvm/x86.c
index 49079a46687b..3944e917e794 100644
--- a/trunk/arch/x86/kvm/x86.c
+++ b/trunk/arch/x86/kvm/x86.c
@@ -338,6 +338,9 @@ EXPORT_SYMBOL_GPL(kvm_lmsw);
 
 void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 {
+	unsigned long old_cr4 = vcpu->arch.cr4;
+	unsigned long pdptr_bits = X86_CR4_PGE | X86_CR4_PSE | X86_CR4_PAE;
+
 	if (cr4 & CR4_RESERVED_BITS) {
 		printk(KERN_DEBUG "set_cr4: #GP, reserved bits\n");
 		kvm_inject_gp(vcpu, 0);
@@ -351,7 +354,8 @@ void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 			kvm_inject_gp(vcpu, 0);
 			return;
 		}
-	} else if (is_paging(vcpu) && !is_pae(vcpu) && (cr4 & X86_CR4_PAE)
+	} else if (is_paging(vcpu) && (cr4 & X86_CR4_PAE)
+		   && ((cr4 ^ old_cr4) & pdptr_bits)
 		   && !load_pdptrs(vcpu, vcpu->arch.cr3)) {
 		printk(KERN_DEBUG "set_cr4: #GP, pdptrs reserved bits\n");
 		kvm_inject_gp(vcpu, 0);