For the triple fault sythesized by KVM, e.g. the RSM path or nested_vmx_abort(), if KVM exits to userspace before the request is serviced, userspace could migrate the VM and lose the triple fault. Fix this issue by adding a new event KVM_VCPUEVENT_TRIPLE_FAULT in get/set_vcpu_events() to track the triple fault request. Signed-off-by: Chenyi Qiang <chenyi.qiang@xxxxxxxxx> --- Documentation/virt/kvm/api.rst | 6 ++++++ arch/x86/include/uapi/asm/kvm.h | 1 + arch/x86/kvm/x86.c | 9 ++++++++- 3 files changed, 15 insertions(+), 1 deletion(-) diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst index 691ff84444bd..9682b0a438bd 100644 --- a/Documentation/virt/kvm/api.rst +++ b/Documentation/virt/kvm/api.rst @@ -1146,6 +1146,9 @@ The following bits are defined in the flags field: fields contain a valid state. This bit will be set whenever KVM_CAP_EXCEPTION_PAYLOAD is enabled. +- KVM_VCPUEVENT_TRIPLE_FAULT may be set to signal that there's a + triple fault request waiting to be serviced. + ARM/ARM64: ^^^^^^^^^^ @@ -1241,6 +1244,9 @@ can be set in the flags field to signal that the exception_has_payload, exception_payload, and exception.pending fields contain a valid state and shall be written into the VCPU. +KVM_VCPUEVENT_TRIPLE_FAULT can be set in flags field to signal that a +triple fault request should be made. + ARM/ARM64: ^^^^^^^^^^ diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h index bf6e96011dfe..d8ef0d993e86 100644 --- a/arch/x86/include/uapi/asm/kvm.h +++ b/arch/x86/include/uapi/asm/kvm.h @@ -325,6 +325,7 @@ struct kvm_reinject_control { #define KVM_VCPUEVENT_VALID_SHADOW 0x00000004 #define KVM_VCPUEVENT_VALID_SMM 0x00000008 #define KVM_VCPUEVENT_VALID_PAYLOAD 0x00000010 +#define KVM_VCPUEVENT_TRIPLE_FAULT 0x00000020 /* Interrupt shadow states */ #define KVM_X86_SHADOW_INT_MOV_SS 0x01 diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4fa4d8269e5b..fee402a700df 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4891,6 +4891,9 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, if (vcpu->kvm->arch.exception_payload_enabled) events->flags |= KVM_VCPUEVENT_VALID_PAYLOAD; + if (kvm_check_request(KVM_REQ_TRIPLE_FAULT, vcpu)) + events->flags |= KVM_VCPUEVENT_TRIPLE_FAULT; + memset(&events->reserved, 0, sizeof(events->reserved)); } @@ -4903,7 +4906,8 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, | KVM_VCPUEVENT_VALID_SIPI_VECTOR | KVM_VCPUEVENT_VALID_SHADOW | KVM_VCPUEVENT_VALID_SMM - | KVM_VCPUEVENT_VALID_PAYLOAD)) + | KVM_VCPUEVENT_VALID_PAYLOAD + | KVM_VCPUEVENT_TRIPLE_FAULT)) return -EINVAL; if (events->flags & KVM_VCPUEVENT_VALID_PAYLOAD) { @@ -4976,6 +4980,9 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu, } } + if (events->flags & KVM_VCPUEVENT_TRIPLE_FAULT) + kvm_make_request(KVM_REQ_TRIPLE_FAULT, vcpu); + kvm_make_request(KVM_REQ_EVENT, vcpu); return 0; -- 2.17.1