From: Wanpeng Li <[email protected]> Add an nested_apf field to vcpu->arch.exception to identify an async page fault, and constructs the expected vm-exit information fields. Force a nested VM exit from nested_vmx_check_exception() if the injected #PF is async page fault. Extending the userspace interface KVM_GET_VCPU_EVENTS and KVM_SET_VCPU_EVENTS for live migration.
Cc: Paolo Bonzini <[email protected]> Cc: Radim Krčmář <[email protected]> Signed-off-by: Wanpeng Li <[email protected]> --- Documentation/virtual/kvm/api.txt | 8 ++++++-- arch/x86/include/asm/kvm_emulate.h | 1 + arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/include/uapi/asm/kvm.h | 3 ++- arch/x86/kvm/svm.c | 16 ++++++++++------ arch/x86/kvm/vmx.c | 17 ++++++++++++++--- arch/x86/kvm/x86.c | 19 +++++++++++++++---- tools/arch/x86/include/uapi/asm/kvm.h | 3 ++- 8 files changed, 52 insertions(+), 17 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 4029943..a991a7c 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -832,7 +832,7 @@ struct kvm_vcpu_events { __u8 injected; __u8 nr; __u8 has_error_code; - __u8 pad; + __u8 nested_apf; __u32 error_code; } exception; struct { @@ -857,7 +857,7 @@ struct kvm_vcpu_events { } smi; }; -Only two fields are defined in the flags field: +Only three fields are defined in the flags field: - KVM_VCPUEVENT_VALID_SHADOW may be set in the flags field to signal that interrupt.shadow contains a valid state. @@ -865,6 +865,9 @@ Only two fields are defined in the flags field: - KVM_VCPUEVENT_VALID_SMM may be set in the flags field to signal that smi contains a valid state. +- KVM_VCPUEVENT_VALID_ASYNC_PF may be set in the flags field to signal that + the exception is an async page fault. + 4.32 KVM_SET_VCPU_EVENTS Capability: KVM_CAP_VCPU_EVENTS @@ -887,6 +890,7 @@ suppress overwriting the current in-kernel state. The bits are: KVM_VCPUEVENT_VALID_NMI_PENDING - transfer nmi.pending to the kernel KVM_VCPUEVENT_VALID_SIPI_VECTOR - transfer sipi_vector KVM_VCPUEVENT_VALID_SMM - transfer the smi sub-struct. +KVM_VCPUEVENT_VALID_ASYNC_PF - transfer async page fault If KVM_CAP_INTR_SHADOW is available, KVM_VCPUEVENT_VALID_SHADOW can be set in the flags field to signal that interrupt.shadow contains a valid state and diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index 722d0e5..fde36f1 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -23,6 +23,7 @@ struct x86_exception { u16 error_code; bool nested_page_fault; u64 address; /* cr2 or nested page fault gpa */ + u8 async_page_fault; }; /* diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index e20d8a8..71aef4b 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -545,6 +545,7 @@ struct kvm_vcpu_arch { bool reinject; u8 nr; u32 error_code; + u8 nested_apf; } exception; struct kvm_queued_interrupt { @@ -646,6 +647,7 @@ struct kvm_vcpu_arch { u32 id; bool send_user_only; u32 host_apf_reason; + unsigned long nested_apf_token; } apf; /* OSVW MSRs (AMD only) */ diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h index c2824d0..c9556ec 100644 --- a/arch/x86/include/uapi/asm/kvm.h +++ b/arch/x86/include/uapi/asm/kvm.h @@ -287,6 +287,7 @@ struct kvm_reinject_control { #define KVM_VCPUEVENT_VALID_SIPI_VECTOR 0x00000002 #define KVM_VCPUEVENT_VALID_SHADOW 0x00000004 #define KVM_VCPUEVENT_VALID_SMM 0x00000008 +#define KVM_VCPUEVENT_VALID_ASYNC_PF 0x00000010 /* Interrupt shadow states */ #define KVM_X86_SHADOW_INT_MOV_SS 0x01 @@ -298,7 +299,7 @@ struct kvm_vcpu_events { __u8 injected; __u8 nr; __u8 has_error_code; - __u8 pad; + __u8 nested_apf; __u32 error_code; } exception; struct { diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 8f263bf..49cdb8e 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -2367,15 +2367,19 @@ static int nested_svm_check_exception(struct vcpu_svm *svm, unsigned nr, if (!is_guest_mode(&svm->vcpu)) return 0; + vmexit = nested_svm_intercept(svm); + if (vmexit != NESTED_EXIT_DONE) + return 0; + svm->vmcb->control.exit_code = SVM_EXIT_EXCP_BASE + nr; svm->vmcb->control.exit_code_hi = 0; svm->vmcb->control.exit_info_1 = error_code; - svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2; - - vmexit = nested_svm_intercept(svm); - if (vmexit == NESTED_EXIT_DONE) - svm->nested.exit_required = true; + if (svm->vcpu.arch.exception.nested_apf) + svm->vmcb->control.exit_info_2 = svm->vcpu.arch.apf.nested_apf_token; + else + svm->vmcb->control.exit_info_2 = svm->vcpu.arch.cr2; + svm->nested.exit_required = true; return vmexit; } @@ -2568,7 +2572,7 @@ static int nested_svm_intercept(struct vcpu_svm *svm) vmexit = NESTED_EXIT_DONE; /* async page fault always cause vmexit */ else if ((exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) && - svm->vcpu.arch.apf.host_apf_reason != 0) + svm->vcpu.arch.exception.nested_apf != 0) vmexit = NESTED_EXIT_DONE; break; } diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index d20f794..8724ea6 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2418,13 +2418,24 @@ static void skip_emulated_instruction(struct kvm_vcpu *vcpu) * KVM wants to inject page-faults which it got to the guest. This function * checks whether in a nested guest, we need to inject them to L1 or L2. */ -static int nested_vmx_check_exception(struct kvm_vcpu *vcpu, unsigned nr) +static int nested_vmx_check_exception(struct kvm_vcpu *vcpu) { struct vmcs12 *vmcs12 = get_vmcs12(vcpu); + unsigned int nr = vcpu->arch.exception.nr; - if (!(vmcs12->exception_bitmap & (1u << nr))) + if (!((vmcs12->exception_bitmap & (1u << nr)) || + (nr == PF_VECTOR && vcpu->arch.exception.nested_apf))) return 0; + if (vcpu->arch.exception.nested_apf) { + vmcs_write32(VM_EXIT_INTR_ERROR_CODE, vcpu->arch.exception.error_code); + nested_vmx_vmexit(vcpu, EXIT_REASON_EXCEPTION_NMI, + PF_VECTOR | INTR_TYPE_HARD_EXCEPTION | + INTR_INFO_DELIVER_CODE_MASK | INTR_INFO_VALID_MASK, + vcpu->arch.apf.nested_apf_token); + return 1; + } + nested_vmx_vmexit(vcpu, EXIT_REASON_EXCEPTION_NMI, vmcs_read32(VM_EXIT_INTR_INFO), vmcs_readl(EXIT_QUALIFICATION)); @@ -2441,7 +2452,7 @@ static void vmx_queue_exception(struct kvm_vcpu *vcpu) u32 intr_info = nr | INTR_INFO_VALID_MASK; if (!reinject && is_guest_mode(vcpu) && - nested_vmx_check_exception(vcpu, nr)) + nested_vmx_check_exception(vcpu)) return; if (has_error_code) { diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 7511c0a..5756811 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -452,7 +452,12 @@ EXPORT_SYMBOL_GPL(kvm_complete_insn_gp); void kvm_inject_page_fault(struct kvm_vcpu *vcpu, struct x86_exception *fault) { ++vcpu->stat.pf_guest; - vcpu->arch.cr2 = fault->address; + vcpu->arch.exception.nested_apf = + is_guest_mode(vcpu) && fault->async_page_fault; + if (vcpu->arch.exception.nested_apf) + vcpu->arch.apf.nested_apf_token = fault->address; + else + vcpu->arch.cr2 = fault->address; kvm_queue_exception_e(vcpu, PF_VECTOR, fault->error_code); } EXPORT_SYMBOL_GPL(kvm_inject_page_fault); @@ -3072,7 +3077,7 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, !kvm_exception_is_soft(vcpu->arch.exception.nr); events->exception.nr = vcpu->arch.exception.nr; events->exception.has_error_code = vcpu->arch.exception.has_error_code; - events->exception.pad = 0; + events->exception.nested_apf = vcpu->arch.exception.nested_apf; events->exception.error_code = vcpu->arch.exception.error_code; events->interrupt.injected = @@ -3096,7 +3101,8 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, events->flags = (KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SHADOW - | KVM_VCPUEVENT_VALID_SMM); + | KVM_VCPUEVENT_VALID_SMM + | KVM_VCPUEVENT_VALID_ASYNC_PF); memset(&events->reserved, 0, sizeof(events->reserved)); } @@ -3108,7 +3114,8 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, if (events->flags & ~(KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SIPI_VECTOR | KVM_VCPUEVENT_VALID_SHADOW - | KVM_VCPUEVENT_VALID_SMM)) + | KVM_VCPUEVENT_VALID_SMM + | KVM_VCPUEVENT_VALID_ASYNC_PF)) return -EINVAL; if (events->exception.injected && @@ -3126,6 +3133,8 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, vcpu->arch.exception.pending = events->exception.injected; vcpu->arch.exception.nr = events->exception.nr; vcpu->arch.exception.has_error_code = events->exception.has_error_code; + if (events->flags & KVM_VCPUEVENT_VALID_ASYNC_PF) + vcpu->arch.exception.nested_apf = events->exception.nested_apf; vcpu->arch.exception.error_code = events->exception.error_code; vcpu->arch.interrupt.pending = events->interrupt.injected; @@ -8573,6 +8582,7 @@ void kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu, fault.error_code = 0; fault.nested_page_fault = false; fault.address = work->arch.token; + fault.async_page_fault = true; kvm_inject_page_fault(vcpu, &fault); } } @@ -8595,6 +8605,7 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, fault.error_code = 0; fault.nested_page_fault = false; fault.address = work->arch.token; + fault.async_page_fault = true; kvm_inject_page_fault(vcpu, &fault); } vcpu->arch.apf.halted = false; diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h index c2824d0..c9556ec 100644 --- a/tools/arch/x86/include/uapi/asm/kvm.h +++ b/tools/arch/x86/include/uapi/asm/kvm.h @@ -287,6 +287,7 @@ struct kvm_reinject_control { #define KVM_VCPUEVENT_VALID_SIPI_VECTOR 0x00000002 #define KVM_VCPUEVENT_VALID_SHADOW 0x00000004 #define KVM_VCPUEVENT_VALID_SMM 0x00000008 +#define KVM_VCPUEVENT_VALID_ASYNC_PF 0x00000010 /* Interrupt shadow states */ #define KVM_X86_SHADOW_INT_MOV_SS 0x01 @@ -298,7 +299,7 @@ struct kvm_vcpu_events { __u8 injected; __u8 nr; __u8 has_error_code; - __u8 pad; + __u8 nested_apf; __u32 error_code; } exception; struct { -- 2.7.4
