From: Nadav Har'El <nyh@math.technion.ac.il>
Date: Wed, 9 May 2012 13:10:44 +0000 (+0300)
Subject: KVM: nVMX: Fix erroneous exception bitmap check
X-Git-Tag: v3.3.6~14
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8dd2cb2a8d183d59f6d41dd71db550a306cc55eb;p=thirdparty%2Fkernel%2Fstable.git

KVM: nVMX: Fix erroneous exception bitmap check

(cherry picked from commit 9587190107d0c0cbaccbf7bf6b0245d29095a9ae)

The code which checks whether to inject a pagefault to L1 or L2 (in
nested VMX) was wrong, incorrect in how it checked the PF_VECTOR bit.
Thanks to Dan Carpenter for spotting this.

Signed-off-by: Nadav Har'El <nyh@il.ibm.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index fafb3256ea5e5..5d1b0c75fffab 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1678,7 +1678,7 @@ static int nested_pf_handled(struct kvm_vcpu *vcpu)
 	struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
 
 	/* TODO: also check PFEC_MATCH/MASK, not just EB.PF. */
-	if (!(vmcs12->exception_bitmap & PF_VECTOR))
+	if (!(vmcs12->exception_bitmap & (1u << PF_VECTOR)))
 		return 0;
 
 	nested_vmx_vmexit(vcpu);