From b18d5431acc7a2fd22767925f3a6f597aa4bd29e Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Mon, 15 Jun 2015 16:55:21 +0800 Subject: [PATCH] KVM: x86: fix CR0.CD virtualization Currently, CR0.CD is not checked when we virtualize memory cache type for noncoherent_dma guests, this patch fixes it by : - setting UC for all memory if CR0.CD = 1 - zapping all the last sptes in MMU if CR0.CD is changed Signed-off-by: Xiao Guangrong Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx.c | 32 ++++++++++++++++++++++---------- arch/x86/kvm/x86.c | 4 ++++ 2 files changed, 26 insertions(+), 10 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 06a186b07631..2764381a1b02 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -8628,7 +8628,8 @@ static int get_ept_level(void) static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { - u64 ret; + u8 cache; + u64 ipat = 0; /* For VT-d and EPT combination * 1. MMIO: always map as UC @@ -8641,16 +8642,27 @@ static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) * 3. EPT without VT-d: always map as WB and set IPAT=1 to keep * consistent with host MTRR */ - if (is_mmio) - ret = MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT; - else if (kvm_arch_has_noncoherent_dma(vcpu->kvm)) - ret = kvm_get_guest_memory_type(vcpu, gfn) << - VMX_EPT_MT_EPTE_SHIFT; - else - ret = (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) - | VMX_EPT_IPAT_BIT; + if (is_mmio) { + cache = MTRR_TYPE_UNCACHABLE; + goto exit; + } - return ret; + if (!kvm_arch_has_noncoherent_dma(vcpu->kvm)) { + ipat = VMX_EPT_IPAT_BIT; + cache = MTRR_TYPE_WRBACK; + goto exit; + } + + if (kvm_read_cr0(vcpu) & X86_CR0_CD) { + ipat = VMX_EPT_IPAT_BIT; + cache = MTRR_TYPE_UNCACHABLE; + goto exit; + } + + cache = kvm_get_guest_memory_type(vcpu, gfn); + +exit: + return (cache << VMX_EPT_MT_EPTE_SHIFT) | ipat; } static int vmx_get_lpage_level(void) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 43f0df7ddc9c..43fdb10c1580 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -621,6 +621,10 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) if ((cr0 ^ old_cr0) & update_bits) kvm_mmu_reset_context(vcpu); + + if ((cr0 ^ old_cr0) & X86_CR0_CD) + kvm_zap_gfn_range(vcpu->kvm, 0, ~0ULL); + return 0; } EXPORT_SYMBOL_GPL(kvm_set_cr0);