From 2c108bfdf0859f16788c15d289b0eed1bfd8363e Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 3 Aug 2009 14:57:54 -0300 Subject: [PATCH] KVM: MMU: Use different shadows when EFER.NXE changes (cherry picked from commit 9645bb56b31a1b70ab9e470387b5264cafc04aa9) A pte that is shadowed when the guest EFER.NXE=1 is not valid when EFER.NXE=0; if bit 63 is set, the pte should cause a fault, and since the shadow EFER always has NX enabled, this won't happen. Fix by using a different shadow page table for different EFER.NXE bits. This allows vcpus to run correctly with different values of EFER.NXE, and for transitions on this bit to be handled correctly without requiring a full flush. Signed-off-by: Avi Kivity Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/x86.c | 3 +++ 2 files changed, 4 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index a9471db9b69..9a9efb031c8 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -185,6 +185,7 @@ union kvm_mmu_page_role { unsigned access:3; unsigned invalid:1; unsigned cr4_pge:1; + unsigned nxe:1; }; }; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b3c4b0be441..bbacdce35c4 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -523,6 +523,9 @@ static void set_efer(struct kvm_vcpu *vcpu, u64 efer) efer |= vcpu->arch.shadow_efer & EFER_LMA; vcpu->arch.shadow_efer = efer; + + vcpu->arch.mmu.base_role.nxe = (efer & EFER_NX) && !tdp_enabled; + kvm_mmu_reset_context(vcpu); } void kvm_enable_efer_bits(u64 mask) -- 2.11.4.GIT