From: Raghavendra Rao Ananta rananta@google.com
When KVM returns to userspace for KVM_EXIT_ARM_SEA, the userspace is encouraged to inject the abort into the guest via KVM_SET_VCPU_EVENTS.
KVM_SET_VCPU_EVENTS currently only allows injecting external data aborts. However, the synchronous external abort that caused KVM_EXIT_ARM_SEA is possible to be an instruction abort. Userspace is already able to tell if an abort is due to data or instruction via kvm_run.arm_sea.esr, by checking its Exception Class value.
Extend the KVM_SET_VCPU_EVENTS ioctl to allow injecting instruction abort into the guest.
Signed-off-by: Jiaqi Yan jiaqiyan@google.com Signed-off-by: Raghavendra Rao Ananta rananta@google.com --- arch/arm64/include/uapi/asm/kvm.h | 3 ++- arch/arm64/kvm/arm.c | 1 + arch/arm64/kvm/guest.c | 13 ++++++++++--- include/uapi/linux/kvm.h | 1 + 4 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index ed5f3892674c7..643e8c4825451 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -184,8 +184,9 @@ struct kvm_vcpu_events { __u8 serror_pending; __u8 serror_has_esr; __u8 ext_dabt_pending; + __u8 ext_iabt_pending; /* Align it to 8 bytes */ - __u8 pad[5]; + __u8 pad[4]; __u64 serror_esr; } exception; __u32 reserved[12]; diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 47544945fba45..dc2efb627f450 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -319,6 +319,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_ARM_IRQ_LINE_LAYOUT_2: case KVM_CAP_ARM_NISV_TO_USER: case KVM_CAP_ARM_INJECT_EXT_DABT: + case KVM_CAP_ARM_INJECT_EXT_IABT: case KVM_CAP_SET_GUEST_DEBUG: case KVM_CAP_VCPU_ATTRIBUTES: case KVM_CAP_PTP_KVM: diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index 2196979a24a32..4917361ecf5cb 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -825,9 +825,9 @@ int __kvm_arm_vcpu_get_events(struct kvm_vcpu *vcpu, events->exception.serror_esr = vcpu_get_vsesr(vcpu);
/* - * We never return a pending ext_dabt here because we deliver it to - * the virtual CPU directly when setting the event and it's no longer - * 'pending' at this point. + * We never return a pending ext_dabt or ext_iabt here because we + * deliver it to the virtual CPU directly when setting the event + * and it's no longer 'pending' at this point. */
return 0; @@ -839,6 +839,7 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, bool serror_pending = events->exception.serror_pending; bool has_esr = events->exception.serror_has_esr; bool ext_dabt_pending = events->exception.ext_dabt_pending; + bool ext_iabt_pending = events->exception.ext_iabt_pending;
if (serror_pending && has_esr) { if (!cpus_have_final_cap(ARM64_HAS_RAS_EXTN)) @@ -852,8 +853,14 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, kvm_inject_vabt(vcpu); }
+ /* DABT and IABT cannot happen at the same time. */ + if (ext_dabt_pending && ext_iabt_pending) + return -EINVAL; + if (ext_dabt_pending) kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu)); + else if (ext_iabt_pending) + kvm_inject_pabt(vcpu, kvm_vcpu_get_hfar(vcpu));
return 0; } diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 79dc4676ff74b..bcf2b95b79123 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -941,6 +941,7 @@ struct kvm_enable_cap { #define KVM_CAP_X86_GUEST_MODE 238 #define KVM_CAP_ARM_WRITABLE_IMP_ID_REGS 239 #define KVM_CAP_ARM_SEA_TO_USER 240 +#define KVM_CAP_ARM_INJECT_EXT_IABT 241
struct kvm_irq_routing_irqchip { __u32 irqchip;