diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c index 54f9358c9e0e..e2285ed8c91d 100644 --- a/arch/arm64/kvm/mmio.c +++ b/arch/arm64/kvm/mmio.c @@ -159,6 +159,9 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa) bool is_write; int len; u8 data_buf[8]; + u64 esr; + + esr = kvm_vcpu_get_esr(vcpu); /* * No valid syndrome? Ask userspace for help if it has @@ -168,7 +171,7 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa) * though, so directly deliver an exception to the guest. */ if (!kvm_vcpu_dabt_isvalid(vcpu)) { - trace_kvm_mmio_nisv(*vcpu_pc(vcpu), kvm_vcpu_get_esr(vcpu), + trace_kvm_mmio_nisv(*vcpu_pc(vcpu), esr, kvm_vcpu_get_hfar(vcpu), fault_ipa); if (vcpu_is_protected(vcpu)) @@ -185,6 +188,28 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa) return -ENOSYS; } + /* + * When (DFSC == 0b00xxxx || DFSC == 0b10101x) && DFSC != 0b0000xx + * ESR_EL2[12:11] describe the Load/Store Type. This allows us to + * punt the LD64B/ST64B/ST64BV/ST64BV0 instructions to userspace, + * which will have to provide a full emulation of these 4 + * instructions. No, we don't expect this do be fast. + * + * We rely on traps being set if the corresponding features are not + * enabled, so if we get here, userspace has promised us to handle + * it already. + */ + switch (kvm_vcpu_trap_get_fault(vcpu)) { + case 0b000100 ... 0b001111: + case 0b101010 ... 0b101011: + if (FIELD_GET(GENMASK(12, 11), esr)) { + run->exit_reason = KVM_EXIT_ARM_LDST64B; + run->arm_nisv.esr_iss = esr & ~(u64)ESR_ELx_FSC; + run->arm_nisv.fault_ipa = fault_ipa; + return 0; + } + } + /* * Prepare MMIO operation. First decode the syndrome data we get * from the CPU. Then try if some in-kernel emulation feels diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index dddb781b0507..88cca0e22ece 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -180,6 +180,7 @@ struct kvm_xen_exit { #define KVM_EXIT_MEMORY_FAULT 39 #define KVM_EXIT_TDX 40 #define KVM_EXIT_ARM_SEA 41 +#define KVM_EXIT_ARM_LDST64B 42 /* For KVM_EXIT_INTERNAL_ERROR */ /* Emulate instruction failed. */ @@ -402,7 +403,7 @@ struct kvm_run { } eoi; /* KVM_EXIT_HYPERV */ struct kvm_hyperv_exit hyperv; - /* KVM_EXIT_ARM_NISV */ + /* KVM_EXIT_ARM_NISV / KVM_EXIT_ARM_LDST64B */ struct { __u64 esr_iss; __u64 fault_ipa;