From d0006530576f1c7a49b2010eac7afdcb5a3613ae Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 11 Aug 2017 18:36:43 +0200 Subject: [PATCH] KVM: SVM: limit kvm_handle_page_fault to #PF handling It has always annoyed me a bit how SVM_EXIT_NPF is handled by pf_interception. This is also the only reason behind the under-documented need_unprotect argument to kvm_handle_page_fault. Let NPF go straight to kvm_mmu_page_fault, just like VMX does in handle_ept_violation and handle_ept_misconfig. Reviewed-by: Brijesh Singh Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 5 ++--- arch/x86/kvm/mmu.h | 3 +-- arch/x86/kvm/svm.c | 15 +++++++++++++-- arch/x86/kvm/vmx.c | 3 +-- 4 files changed, 17 insertions(+), 9 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index d7a7eafc5ade..e4fb82c0a5d0 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3820,8 +3820,7 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn, } int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code, - u64 fault_address, char *insn, int insn_len, - bool need_unprotect) + u64 fault_address, char *insn, int insn_len) { int r = 1; @@ -3829,7 +3828,7 @@ int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code, default: trace_kvm_page_fault(fault_address, error_code); - if (need_unprotect && kvm_event_needs_reinjection(vcpu)) + if (kvm_event_needs_reinjection(vcpu)) kvm_mmu_unprotect_page_virt(vcpu, fault_address); r = kvm_mmu_page_fault(vcpu, fault_address, error_code, insn, insn_len); diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index 64a2dbd2b1af..1092302aa16a 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -65,8 +65,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly, bool accessed_dirty); bool kvm_can_do_async_pf(struct kvm_vcpu *vcpu); int kvm_handle_page_fault(struct kvm_vcpu *vcpu, u64 error_code, - u64 fault_address, char *insn, int insn_len, - bool need_unprotect); + u64 fault_address, char *insn, int insn_len); static inline unsigned int kvm_mmu_available_pages(struct kvm *kvm) { diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 3e4337ee59cb..84f18634d87c 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2141,7 +2141,18 @@ static int pf_interception(struct vcpu_svm *svm) return kvm_handle_page_fault(&svm->vcpu, error_code, fault_address, svm->vmcb->control.insn_bytes, - svm->vmcb->control.insn_len, !npt_enabled); + svm->vmcb->control.insn_len); +} + +static int npf_interception(struct vcpu_svm *svm) +{ + u64 fault_address = svm->vmcb->control.exit_info_2; + u64 error_code = svm->vmcb->control.exit_info_1; + + trace_kvm_page_fault(fault_address, error_code); + return kvm_mmu_page_fault(&svm->vcpu, fault_address, error_code, + svm->vmcb->control.insn_bytes, + svm->vmcb->control.insn_len); } static int db_interception(struct vcpu_svm *svm) @@ -4128,7 +4139,7 @@ static int (*const svm_exit_handlers[])(struct vcpu_svm *svm) = { [SVM_EXIT_MONITOR] = monitor_interception, [SVM_EXIT_MWAIT] = mwait_interception, [SVM_EXIT_XSETBV] = xsetbv_interception, - [SVM_EXIT_NPF] = pf_interception, + [SVM_EXIT_NPF] = npf_interception, [SVM_EXIT_RSM] = emulate_on_interception, [SVM_EXIT_AVIC_INCOMPLETE_IPI] = avic_incomplete_ipi_interception, [SVM_EXIT_AVIC_UNACCELERATED_ACCESS] = avic_unaccelerated_access_interception, diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 74582375e0be..c9214e3a01df 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5894,8 +5894,7 @@ static int handle_exception(struct kvm_vcpu *vcpu) cr2 = vmcs_readl(EXIT_QUALIFICATION); /* EPT won't cause page fault directly */ WARN_ON_ONCE(!vcpu->arch.apf.host_apf_reason && enable_ept); - return kvm_handle_page_fault(vcpu, error_code, cr2, NULL, 0, - true); + return kvm_handle_page_fault(vcpu, error_code, cr2, NULL, 0); } ex_no = intr_info & INTR_INFO_VECTOR_MASK; -- 2.11.0