From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: [patch 1/2] KVM: MMU: make __kvm_mmu_free_some_pages handle empty list
Date: Tue, 28 Jul 2009 15:26:58 -0300
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Cc: Izik Eidus <ieidus@redhat.com>, kvm@vger.kernel.org,
	Marcelo Tosatti <mtosatti@redhat.com>
To: Avi Kivity <avi@redhat.com>
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From: Izik Eidus <ieidus@redhat.com>

First check if the list is empty before attempting to look at list
entries.

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: kvm/arch/x86/kvm/mmu.c
===================================================================
--- kvm.orig/arch/x86/kvm/mmu.c
+++ kvm/arch/x86/kvm/mmu.c
@@ -2625,7 +2625,8 @@ EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page
 
 void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
 {
-	while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES) {
+	while (vcpu->kvm->arch.n_free_mmu_pages < KVM_REFILL_PAGES &&
+	       !list_empty(&vcpu->kvm->arch.active_mmu_pages)) {
 		struct kvm_mmu_page *sp;
 
 		sp = container_of(vcpu->kvm->arch.active_mmu_pages.prev,