From 649497d1a3676020802ebba04a3d9bb31253adb5 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Tue, 28 Dec 2010 12:09:07 +0200 Subject: [PATCH] KVM: MMU: Fix incorrect direct gfn for unpaged mode shadow We use the physical address instead of the base gfn for the four PAE page directories we use in unpaged mode. When the guest accesses an address above 1GB that is backed by a large host page, a BUG_ON() in kvm_mmu_set_gfn() triggers. Resolves: https://bugzilla.kernel.org/show_bug.cgi?id=21962 Reported-and-tested-by: Nicolas Prochazka KVM-Stable-Tag. Signed-off-by: Avi Kivity --- arch/x86/kvm/mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index fb8b376bf28c..fbb04aee8301 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2394,7 +2394,8 @@ static int mmu_alloc_direct_roots(struct kvm_vcpu *vcpu) ASSERT(!VALID_PAGE(root)); spin_lock(&vcpu->kvm->mmu_lock); kvm_mmu_free_some_pages(vcpu); - sp = kvm_mmu_get_page(vcpu, i << 30, i << 30, + sp = kvm_mmu_get_page(vcpu, i << (30 - PAGE_SHIFT), + i << 30, PT32_ROOT_LEVEL, 1, ACC_ALL, NULL); root = __pa(sp->spt); -- 2.20.1