From 87778d60eefaa7de1973d8dfbda517cae5e8224a Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Sun, 21 Dec 2008 19:27:36 +0200 Subject: [PATCH] KVM: MMU: Segregate mmu pages created with different cr4.pge settings Don't allow a vcpu with cr4.pge cleared to use a shadow page created with cr4.pge set; this might cause a cr3 switch not to sync ptes that have the global bit set (the global bit has no effect if !cr4.pge). This can only occur on smp with different cr4.pge settings for different vcpus (since a cr4 change will resync the shadow ptes), but there's no cost to being correct here. Signed-off-by: Avi Kivity --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/x86.c | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index f49bfd04b91d6..ab8ef1d117f2a 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -183,6 +183,7 @@ union kvm_mmu_page_role { unsigned metaphysical:1; unsigned access:3; unsigned invalid:1; + unsigned cr4_pge:1; }; }; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c4da7fbabe01e..aa4575c3b6579 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -363,6 +363,7 @@ void kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) } kvm_x86_ops->set_cr4(vcpu, cr4); vcpu->arch.cr4 = cr4; + vcpu->arch.mmu.base_role.cr4_pge = !!(cr4 & X86_CR4_PGE); kvm_mmu_sync_global(vcpu); kvm_mmu_reset_context(vcpu); } -- 2.51.0