From ee1fa209f5e5ca5c1e76c7aa1c2aab292f371f4a Mon Sep 17 00:00:00 2001 From: Junaid Shahid Date: Fri, 20 Mar 2020 14:28:03 -0700 Subject: [PATCH] KVM: x86: Sync SPTEs when injecting page/EPT fault into L1 When injecting a page fault or EPT violation/misconfiguration, KVM is not syncing any shadow PTEs associated with the faulting address, including those in previous MMUs that are associated with L1's current EPTP (in a nested EPT scenario), nor is it flushing any hardware TLB entries. All this is done by kvm_mmu_invalidate_gva. Page faults that are either !PRESENT or RSVD are exempt from the flushing, as the CPU is not allowed to cache such translations. Signed-off-by: Junaid Shahid Co-developed-by: Sean Christopherson Signed-off-by: Sean Christopherson Message-Id: <20200320212833.3507-8-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx/nested.c | 12 ++++++------ arch/x86/kvm/vmx/vmx.c | 2 +- arch/x86/kvm/x86.c | 11 ++++++++++- 3 files changed, 17 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 8f3ff07..d0857bf 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -4560,7 +4560,7 @@ static int nested_vmx_get_vmptr(struct kvm_vcpu *vcpu, gpa_t *vmpointer) return 1; if (kvm_read_guest_virt(vcpu, gva, vmpointer, sizeof(*vmpointer), &e)) { - kvm_inject_page_fault(vcpu, &e); + kvm_inject_emulated_page_fault(vcpu, &e); return 1; } @@ -4869,7 +4869,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu) return 1; /* _system ok, nested_vmx_check_permission has verified cpl=0 */ if (kvm_write_guest_virt_system(vcpu, gva, &value, len, &e)) { - kvm_inject_page_fault(vcpu, &e); + kvm_inject_emulated_page_fault(vcpu, &e); return 1; } } @@ -4943,7 +4943,7 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) instr_info, false, len, &gva)) return 1; if (kvm_read_guest_virt(vcpu, gva, &value, len, &e)) { - kvm_inject_page_fault(vcpu, &e); + kvm_inject_emulated_page_fault(vcpu, &e); return 1; } } @@ -5108,7 +5108,7 @@ static int handle_vmptrst(struct kvm_vcpu *vcpu) /* *_system ok, nested_vmx_check_permission has verified cpl=0 */ if (kvm_write_guest_virt_system(vcpu, gva, (void *)¤t_vmptr, sizeof(gpa_t), &e)) { - kvm_inject_page_fault(vcpu, &e); + kvm_inject_emulated_page_fault(vcpu, &e); return 1; } return nested_vmx_succeed(vcpu); @@ -5152,7 +5152,7 @@ static int handle_invept(struct kvm_vcpu *vcpu) vmx_instruction_info, false, sizeof(operand), &gva)) return 1; if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) { - kvm_inject_page_fault(vcpu, &e); + kvm_inject_emulated_page_fault(vcpu, &e); return 1; } @@ -5220,7 +5220,7 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) vmx_instruction_info, false, sizeof(operand), &gva)) return 1; if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) { - kvm_inject_page_fault(vcpu, &e); + kvm_inject_emulated_page_fault(vcpu, &e); return 1; } if (operand.vpid >> 16) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 0133009..e671bcf 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -5393,7 +5393,7 @@ static int handle_invpcid(struct kvm_vcpu *vcpu) return 1; if (kvm_read_guest_virt(vcpu, gva, &operand, sizeof(operand), &e)) { - kvm_inject_page_fault(vcpu, &e); + kvm_inject_emulated_page_fault(vcpu, &e); return 1; } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2ab821f..3984574 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -619,8 +619,17 @@ bool kvm_inject_emulated_page_fault(struct kvm_vcpu *vcpu, fault_mmu = fault->nested_page_fault ? vcpu->arch.mmu : vcpu->arch.walk_mmu; - fault_mmu->inject_page_fault(vcpu, fault); + /* + * Invalidate the TLB entry for the faulting address, if it exists, + * else the access will fault indefinitely (and to emulate hardware). + */ + if ((fault->error_code & PFERR_PRESENT_MASK) && + !(fault->error_code & PFERR_RSVD_MASK)) + kvm_mmu_invalidate_gva(vcpu, fault_mmu, fault->address, + fault_mmu->root_hpa); + + fault_mmu->inject_page_fault(vcpu, fault); return fault->nested_page_fault; } EXPORT_SYMBOL_GPL(kvm_inject_emulated_page_fault); -- 2.7.4