From d4963e319f1f7851a098df6610a27f9f4cf6d42a Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 30 Aug 2022 23:16:01 +0000 Subject: [PATCH] KVM: x86: Make kvm_queued_exception a properly named, visible struct Move the definition of "struct kvm_queued_exception" out of kvm_vcpu_arch in anticipation of adding a second instance in kvm_vcpu_arch to handle exceptions that occur when vectoring an injected exception and are morphed to VM-Exit instead of leading to #DF. Opportunistically take advantage of the churn to rename "nr" to "vector". No functional change intended. Signed-off-by: Sean Christopherson Reviewed-by: Maxim Levitsky Link: https://lore.kernel.org/r/20220830231614.3580124-15-seanjc@google.com Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 23 ++++++------ arch/x86/kvm/svm/nested.c | 47 ++++++++++++------------ arch/x86/kvm/svm/svm.c | 14 ++++---- arch/x86/kvm/vmx/nested.c | 42 +++++++++++----------- arch/x86/kvm/vmx/vmx.c | 20 +++++------ arch/x86/kvm/x86.c | 80 ++++++++++++++++++++--------------------- arch/x86/kvm/x86.h | 3 +- 7 files changed, 113 insertions(+), 116 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 032d997..76fda10b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -641,6 +641,17 @@ struct kvm_vcpu_xen { struct timer_list poll_timer; }; +struct kvm_queued_exception { + bool pending; + bool injected; + bool has_error_code; + u8 vector; + u32 error_code; + unsigned long payload; + bool has_payload; + u8 nested_apf; +}; + struct kvm_vcpu_arch { /* * rip and regs accesses must go through @@ -739,16 +750,8 @@ struct kvm_vcpu_arch { u8 event_exit_inst_len; - struct kvm_queued_exception { - bool pending; - bool injected; - bool has_error_code; - u8 nr; - u32 error_code; - unsigned long payload; - bool has_payload; - u8 nested_apf; - } exception; + /* Exceptions to be injected to the guest. */ + struct kvm_queued_exception exception; struct kvm_queued_interrupt { bool injected; diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 66f63e5..bbfbcea 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -468,7 +468,7 @@ static void nested_save_pending_event_to_vmcb12(struct vcpu_svm *svm, unsigned int nr; if (vcpu->arch.exception.injected) { - nr = vcpu->arch.exception.nr; + nr = vcpu->arch.exception.vector; exit_int_info = nr | SVM_EVTINJ_VALID | SVM_EVTINJ_TYPE_EXEPT; if (vcpu->arch.exception.has_error_code) { @@ -1310,42 +1310,45 @@ int nested_svm_check_permissions(struct kvm_vcpu *vcpu) static bool nested_exit_on_exception(struct vcpu_svm *svm) { - unsigned int nr = svm->vcpu.arch.exception.nr; + unsigned int vector = svm->vcpu.arch.exception.vector; - return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(nr)); + return (svm->nested.ctl.intercepts[INTERCEPT_EXCEPTION] & BIT(vector)); } -static void nested_svm_inject_exception_vmexit(struct vcpu_svm *svm) +static void nested_svm_inject_exception_vmexit(struct kvm_vcpu *vcpu) { - unsigned int nr = svm->vcpu.arch.exception.nr; + struct kvm_queued_exception *ex = &vcpu->arch.exception; + struct vcpu_svm *svm = to_svm(vcpu); struct vmcb *vmcb = svm->vmcb; - vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr; + vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + ex->vector; vmcb->control.exit_code_hi = 0; - if (svm->vcpu.arch.exception.has_error_code) - vmcb->control.exit_info_1 = svm->vcpu.arch.exception.error_code; + if (ex->has_error_code) + vmcb->control.exit_info_1 = ex->error_code; /* * EXITINFO2 is undefined for all exception intercepts other * than #PF. */ - if (nr == PF_VECTOR) { - if (svm->vcpu.arch.exception.nested_apf) - vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token; - else if (svm->vcpu.arch.exception.has_payload) - vmcb->control.exit_info_2 = svm->vcpu.arch.exception.payload; + if (ex->vector == PF_VECTOR) { + if (ex->nested_apf) + vmcb->control.exit_info_2 = vcpu->arch.apf.nested_apf_token; + else if (ex->has_payload) + vmcb->control.exit_info_2 = ex->payload; else - vmcb->control.exit_info_2 = svm->vcpu.arch.cr2; - } else if (nr == DB_VECTOR) { + vmcb->control.exit_info_2 = vcpu->arch.cr2; + } else if (ex->vector == DB_VECTOR) { /* See inject_pending_event. */ - kvm_deliver_exception_payload(&svm->vcpu); - if (svm->vcpu.arch.dr7 & DR7_GD) { - svm->vcpu.arch.dr7 &= ~DR7_GD; - kvm_update_dr7(&svm->vcpu); + kvm_deliver_exception_payload(vcpu, ex); + + if (vcpu->arch.dr7 & DR7_GD) { + vcpu->arch.dr7 &= ~DR7_GD; + kvm_update_dr7(vcpu); } - } else - WARN_ON(svm->vcpu.arch.exception.has_payload); + } else { + WARN_ON(ex->has_payload); + } nested_svm_vmexit(svm); } @@ -1383,7 +1386,7 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu) return -EBUSY; if (!nested_exit_on_exception(svm)) return 0; - nested_svm_inject_exception_vmexit(svm); + nested_svm_inject_exception_vmexit(vcpu); return 0; } diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 65a72af..0d7b8f7 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -463,22 +463,20 @@ static int svm_update_soft_interrupt_rip(struct kvm_vcpu *vcpu) static void svm_inject_exception(struct kvm_vcpu *vcpu) { + struct kvm_queued_exception *ex = &vcpu->arch.exception; struct vcpu_svm *svm = to_svm(vcpu); - unsigned nr = vcpu->arch.exception.nr; - bool has_error_code = vcpu->arch.exception.has_error_code; - u32 error_code = vcpu->arch.exception.error_code; - kvm_deliver_exception_payload(vcpu); + kvm_deliver_exception_payload(vcpu, ex); - if (kvm_exception_is_soft(nr) && + if (kvm_exception_is_soft(ex->vector) && svm_update_soft_interrupt_rip(vcpu)) return; - svm->vmcb->control.event_inj = nr + svm->vmcb->control.event_inj = ex->vector | SVM_EVTINJ_VALID - | (has_error_code ? SVM_EVTINJ_VALID_ERR : 0) + | (ex->has_error_code ? SVM_EVTINJ_VALID_ERR : 0) | SVM_EVTINJ_TYPE_EXEPT; - svm->vmcb->control.event_inj_err = error_code; + svm->vmcb->control.event_inj_err = ex->error_code; } static void svm_init_erratum_383(void) diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index cb1b3d1..8e7f8ce 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -446,29 +446,27 @@ static bool nested_vmx_is_page_fault_vmexit(struct vmcs12 *vmcs12, */ static int nested_vmx_check_exception(struct kvm_vcpu *vcpu, unsigned long *exit_qual) { + struct kvm_queued_exception *ex = &vcpu->arch.exception; struct vmcs12 *vmcs12 = get_vmcs12(vcpu); - unsigned int nr = vcpu->arch.exception.nr; - bool has_payload = vcpu->arch.exception.has_payload; - unsigned long payload = vcpu->arch.exception.payload; - if (nr == PF_VECTOR) { - if (vcpu->arch.exception.nested_apf) { + if (ex->vector == PF_VECTOR) { + if (ex->nested_apf) { *exit_qual = vcpu->arch.apf.nested_apf_token; return 1; } - if (nested_vmx_is_page_fault_vmexit(vmcs12, - vcpu->arch.exception.error_code)) { - *exit_qual = has_payload ? payload : vcpu->arch.cr2; + if (nested_vmx_is_page_fault_vmexit(vmcs12, ex->error_code)) { + *exit_qual = ex->has_payload ? ex->payload : vcpu->arch.cr2; return 1; } - } else if (vmcs12->exception_bitmap & (1u << nr)) { - if (nr == DB_VECTOR) { - if (!has_payload) { - payload = vcpu->arch.dr6; - payload &= ~DR6_BT; - payload ^= DR6_ACTIVE_LOW; + } else if (vmcs12->exception_bitmap & (1u << ex->vector)) { + if (ex->vector == DB_VECTOR) { + if (ex->has_payload) { + *exit_qual = ex->payload; + } else { + *exit_qual = vcpu->arch.dr6; + *exit_qual &= ~DR6_BT; + *exit_qual ^= DR6_ACTIVE_LOW; } - *exit_qual = payload; } else *exit_qual = 0; return 1; @@ -3764,7 +3762,7 @@ static void vmcs12_save_pending_event(struct kvm_vcpu *vcpu, is_double_fault(exit_intr_info))) { vmcs12->idt_vectoring_info_field = 0; } else if (vcpu->arch.exception.injected) { - nr = vcpu->arch.exception.nr; + nr = vcpu->arch.exception.vector; idt_vectoring = nr | VECTORING_INFO_VALID_MASK; if (kvm_exception_is_soft(nr)) { @@ -3868,11 +3866,11 @@ mmio_needed: static void nested_vmx_inject_exception_vmexit(struct kvm_vcpu *vcpu, unsigned long exit_qual) { + struct kvm_queued_exception *ex = &vcpu->arch.exception; + u32 intr_info = ex->vector | INTR_INFO_VALID_MASK; struct vmcs12 *vmcs12 = get_vmcs12(vcpu); - unsigned int nr = vcpu->arch.exception.nr; - u32 intr_info = nr | INTR_INFO_VALID_MASK; - if (vcpu->arch.exception.has_error_code) { + if (ex->has_error_code) { /* * Intel CPUs do not generate error codes with bits 31:16 set, * and more importantly VMX disallows setting bits 31:16 in the @@ -3882,11 +3880,11 @@ static void nested_vmx_inject_exception_vmexit(struct kvm_vcpu *vcpu, * generate "full" 32-bit error codes, so KVM allows userspace * to inject exception error codes with bits 31:16 set. */ - vmcs12->vm_exit_intr_error_code = (u16)vcpu->arch.exception.error_code; + vmcs12->vm_exit_intr_error_code = (u16)ex->error_code; intr_info |= INTR_INFO_DELIVER_CODE_MASK; } - if (kvm_exception_is_soft(nr)) + if (kvm_exception_is_soft(ex->vector)) intr_info |= INTR_TYPE_SOFT_EXCEPTION; else intr_info |= INTR_TYPE_HARD_EXCEPTION; @@ -3917,7 +3915,7 @@ static void nested_vmx_inject_exception_vmexit(struct kvm_vcpu *vcpu, static inline unsigned long vmx_get_pending_dbg_trap(struct kvm_vcpu *vcpu) { if (!vcpu->arch.exception.pending || - vcpu->arch.exception.nr != DB_VECTOR) + vcpu->arch.exception.vector != DB_VECTOR) return 0; /* General Detect #DBs are always fault-like. */ diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index d046df6..f555be2 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1659,7 +1659,7 @@ static void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu) */ if (nested_cpu_has_mtf(vmcs12) && (!vcpu->arch.exception.pending || - vcpu->arch.exception.nr == DB_VECTOR)) + vcpu->arch.exception.vector == DB_VECTOR)) vmx->nested.mtf_pending = true; else vmx->nested.mtf_pending = false; @@ -1686,15 +1686,13 @@ static void vmx_clear_hlt(struct kvm_vcpu *vcpu) static void vmx_inject_exception(struct kvm_vcpu *vcpu) { + struct kvm_queued_exception *ex = &vcpu->arch.exception; + u32 intr_info = ex->vector | INTR_INFO_VALID_MASK; struct vcpu_vmx *vmx = to_vmx(vcpu); - unsigned nr = vcpu->arch.exception.nr; - bool has_error_code = vcpu->arch.exception.has_error_code; - u32 error_code = vcpu->arch.exception.error_code; - u32 intr_info = nr | INTR_INFO_VALID_MASK; - kvm_deliver_exception_payload(vcpu); + kvm_deliver_exception_payload(vcpu, ex); - if (has_error_code) { + if (ex->has_error_code) { /* * Despite the error code being architecturally defined as 32 * bits, and the VMCS field being 32 bits, Intel CPUs and thus @@ -1705,21 +1703,21 @@ static void vmx_inject_exception(struct kvm_vcpu *vcpu) * the upper bits to avoid VM-Fail, losing information that * does't really exist is preferable to killing the VM. */ - vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE, (u16)error_code); + vmcs_write32(VM_ENTRY_EXCEPTION_ERROR_CODE, (u16)ex->error_code); intr_info |= INTR_INFO_DELIVER_CODE_MASK; } if (vmx->rmode.vm86_active) { int inc_eip = 0; - if (kvm_exception_is_soft(nr)) + if (kvm_exception_is_soft(ex->vector)) inc_eip = vcpu->arch.event_exit_inst_len; - kvm_inject_realmode_interrupt(vcpu, nr, inc_eip); + kvm_inject_realmode_interrupt(vcpu, ex->vector, inc_eip); return; } WARN_ON_ONCE(vmx->emulation_required); - if (kvm_exception_is_soft(nr)) { + if (kvm_exception_is_soft(ex->vector)) { vmcs_write32(VM_ENTRY_INSTRUCTION_LEN, vmx->vcpu.arch.event_exit_inst_len); intr_info |= INTR_TYPE_SOFT_EXCEPTION; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4cb177b..b156dde 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -561,16 +561,13 @@ static int exception_type(int vector) return EXCPT_FAULT; } -void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu) +void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu, + struct kvm_queued_exception *ex) { - unsigned nr = vcpu->arch.exception.nr; - bool has_payload = vcpu->arch.exception.has_payload; - unsigned long payload = vcpu->arch.exception.payload; - - if (!has_payload) + if (!ex->has_payload) return; - switch (nr) { + switch (ex->vector) { case DB_VECTOR: /* * "Certain debug exceptions may clear bit 0-3. The @@ -595,8 +592,8 @@ void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu) * So they need to be flipped for DR6. */ vcpu->arch.dr6 |= DR6_ACTIVE_LOW; - vcpu->arch.dr6 |= payload; - vcpu->arch.dr6 ^= payload & DR6_ACTIVE_LOW; + vcpu->arch.dr6 |= ex->payload; + vcpu->arch.dr6 ^= ex->payload & DR6_ACTIVE_LOW; /* * The #DB payload is defined as compatible with the 'pending @@ -607,12 +604,12 @@ void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu) vcpu->arch.dr6 &= ~BIT(12); break; case PF_VECTOR: - vcpu->arch.cr2 = payload; + vcpu->arch.cr2 = ex->payload; break; } - vcpu->arch.exception.has_payload = false; - vcpu->arch.exception.payload = 0; + ex->has_payload = false; + ex->payload = 0; } EXPORT_SYMBOL_GPL(kvm_deliver_exception_payload); @@ -651,17 +648,18 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu, vcpu->arch.exception.injected = false; } vcpu->arch.exception.has_error_code = has_error; - vcpu->arch.exception.nr = nr; + vcpu->arch.exception.vector = nr; vcpu->arch.exception.error_code = error_code; vcpu->arch.exception.has_payload = has_payload; vcpu->arch.exception.payload = payload; if (!is_guest_mode(vcpu)) - kvm_deliver_exception_payload(vcpu); + kvm_deliver_exception_payload(vcpu, + &vcpu->arch.exception); return; } /* to check exception */ - prev_nr = vcpu->arch.exception.nr; + prev_nr = vcpu->arch.exception.vector; if (prev_nr == DF_VECTOR) { /* triple fault -> shutdown */ kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); @@ -679,7 +677,7 @@ static void kvm_multiple_exception(struct kvm_vcpu *vcpu, vcpu->arch.exception.pending = true; vcpu->arch.exception.injected = false; vcpu->arch.exception.has_error_code = true; - vcpu->arch.exception.nr = DF_VECTOR; + vcpu->arch.exception.vector = DF_VECTOR; vcpu->arch.exception.error_code = 0; vcpu->arch.exception.has_payload = false; vcpu->arch.exception.payload = 0; @@ -5015,25 +5013,24 @@ static int kvm_vcpu_ioctl_x86_set_mce(struct kvm_vcpu *vcpu, static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, struct kvm_vcpu_events *events) { + struct kvm_queued_exception *ex = &vcpu->arch.exception; + process_nmi(vcpu); if (kvm_check_request(KVM_REQ_SMI, vcpu)) process_smi(vcpu); /* - * In guest mode, payload delivery should be deferred, - * so that the L1 hypervisor can intercept #PF before - * CR2 is modified (or intercept #DB before DR6 is - * modified under nVMX). Unless the per-VM capability, - * KVM_CAP_EXCEPTION_PAYLOAD, is set, we may not defer the delivery of - * an exception payload and handle after a KVM_GET_VCPU_EVENTS. Since we - * opportunistically defer the exception payload, deliver it if the - * capability hasn't been requested before processing a - * KVM_GET_VCPU_EVENTS. + * In guest mode, payload delivery should be deferred if the exception + * will be intercepted by L1, e.g. KVM should not modifying CR2 if L1 + * intercepts #PF, ditto for DR6 and #DBs. If the per-VM capability, + * KVM_CAP_EXCEPTION_PAYLOAD, is not set, userspace may or may not + * propagate the payload and so it cannot be safely deferred. Deliver + * the payload if the capability hasn't been requested. */ if (!vcpu->kvm->arch.exception_payload_enabled && - vcpu->arch.exception.pending && vcpu->arch.exception.has_payload) - kvm_deliver_exception_payload(vcpu); + ex->pending && ex->has_payload) + kvm_deliver_exception_payload(vcpu, ex); /* * The API doesn't provide the instruction length for software @@ -5041,26 +5038,25 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, * isn't advanced, we should expect to encounter the exception * again. */ - if (kvm_exception_is_soft(vcpu->arch.exception.nr)) { + if (kvm_exception_is_soft(ex->vector)) { events->exception.injected = 0; events->exception.pending = 0; } else { - events->exception.injected = vcpu->arch.exception.injected; - events->exception.pending = vcpu->arch.exception.pending; + events->exception.injected = ex->injected; + events->exception.pending = ex->pending; /* * For ABI compatibility, deliberately conflate * pending and injected exceptions when * KVM_CAP_EXCEPTION_PAYLOAD isn't enabled. */ if (!vcpu->kvm->arch.exception_payload_enabled) - events->exception.injected |= - vcpu->arch.exception.pending; + events->exception.injected |= ex->pending; } - events->exception.nr = vcpu->arch.exception.nr; - events->exception.has_error_code = vcpu->arch.exception.has_error_code; - events->exception.error_code = vcpu->arch.exception.error_code; - events->exception_has_payload = vcpu->arch.exception.has_payload; - events->exception_payload = vcpu->arch.exception.payload; + events->exception.nr = ex->vector; + events->exception.has_error_code = ex->has_error_code; + events->exception.error_code = ex->error_code; + events->exception_has_payload = ex->has_payload; + events->exception_payload = ex->payload; events->interrupt.injected = vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft; @@ -5132,7 +5128,7 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, process_nmi(vcpu); vcpu->arch.exception.injected = events->exception.injected; vcpu->arch.exception.pending = events->exception.pending; - vcpu->arch.exception.nr = events->exception.nr; + vcpu->arch.exception.vector = events->exception.nr; vcpu->arch.exception.has_error_code = events->exception.has_error_code; vcpu->arch.exception.error_code = events->exception.error_code; vcpu->arch.exception.has_payload = events->exception_has_payload; @@ -9718,7 +9714,7 @@ int kvm_check_nested_events(struct kvm_vcpu *vcpu) static void kvm_inject_exception(struct kvm_vcpu *vcpu) { - trace_kvm_inj_exception(vcpu->arch.exception.nr, + trace_kvm_inj_exception(vcpu->arch.exception.vector, vcpu->arch.exception.has_error_code, vcpu->arch.exception.error_code, vcpu->arch.exception.injected); @@ -9790,12 +9786,12 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool *req_immediate_exit) * describe the behavior of General Detect #DBs, which are * fault-like. They do _not_ set RF, a la code breakpoints. */ - if (exception_type(vcpu->arch.exception.nr) == EXCPT_FAULT) + if (exception_type(vcpu->arch.exception.vector) == EXCPT_FAULT) __kvm_set_rflags(vcpu, kvm_get_rflags(vcpu) | X86_EFLAGS_RF); - if (vcpu->arch.exception.nr == DB_VECTOR) { - kvm_deliver_exception_payload(vcpu); + if (vcpu->arch.exception.vector == DB_VECTOR) { + kvm_deliver_exception_payload(vcpu, &vcpu->arch.exception); if (vcpu->arch.dr7 & DR7_GD) { vcpu->arch.dr7 &= ~DR7_GD; kvm_update_dr7(vcpu); diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 1926d2c..4147d27 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -286,7 +286,8 @@ int kvm_write_guest_virt_system(struct kvm_vcpu *vcpu, int handle_ud(struct kvm_vcpu *vcpu); -void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu); +void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu, + struct kvm_queued_exception *ex); void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu); u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn); -- 2.7.4