1 files changed, 43 insertions, 5 deletions

diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c
index 3dd38a151d2a..54f9358c9e0e 100644
--- a/arch/arm64/kvm/mmio.c
+++ b/arch/arm64/kvm/mmio.c
@@ -72,6 +72,33 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len)
 	return data;
 }
 
+static bool kvm_pending_external_abort(struct kvm_vcpu *vcpu)
+{
+	if (!vcpu_get_flag(vcpu, PENDING_EXCEPTION))
+		return false;
+
+	if (vcpu_el1_is_32bit(vcpu)) {
+		switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) {
+		case unpack_vcpu_flag(EXCEPT_AA32_UND):
+		case unpack_vcpu_flag(EXCEPT_AA32_IABT):
+		case unpack_vcpu_flag(EXCEPT_AA32_DABT):
+			return true;
+		default:
+			return false;
+		}
+	} else {
+		switch (vcpu_get_flag(vcpu, EXCEPT_MASK)) {
+		case unpack_vcpu_flag(EXCEPT_AA64_EL1_SYNC):
+		case unpack_vcpu_flag(EXCEPT_AA64_EL2_SYNC):
+		case unpack_vcpu_flag(EXCEPT_AA64_EL1_SERR):
+		case unpack_vcpu_flag(EXCEPT_AA64_EL2_SERR):
+			return true;
+		default:
+			return false;
+		}
+	}
+}
+
 /**
  * kvm_handle_mmio_return -- Handle MMIO loads after user space emulation
  *			     or in-kernel IO emulation
@@ -84,9 +111,12 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu)
 	unsigned int len;
 	int mask;
 
-	/* Detect an already handled MMIO return */
-	if (unlikely(!vcpu->mmio_needed))
-		return 0;
+	/*
+	 * Detect if the MMIO return was already handled or if userspace aborted
+	 * the MMIO access.
+	 */
+	if (unlikely(!vcpu->mmio_needed || kvm_pending_external_abort(vcpu)))
+		return 1;
 
 	vcpu->mmio_needed = 0;
 
@@ -117,7 +147,7 @@ int kvm_handle_mmio_return(struct kvm_vcpu *vcpu)
 	 */
 	kvm_incr_pc(vcpu);
 
-	return 0;
+	return 1;
 }
 
 int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
@@ -133,8 +163,17 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
 	/*
 	 * No valid syndrome? Ask userspace for help if it has
 	 * volunteered to do so, and bail out otherwise.
+	 *
+	 * In the protected VM case, there isn't much userspace can do
+	 * 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),
+				    kvm_vcpu_get_hfar(vcpu), fault_ipa);
+
+		if (vcpu_is_protected(vcpu))
+			return kvm_inject_sea_dabt(vcpu, kvm_vcpu_get_hfar(vcpu));
+
 		if (test_bit(KVM_ARCH_FLAG_RETURN_NISV_IO_ABORT_TO_USER,
 			     &vcpu->kvm->arch.flags)) {
 			run->exit_reason = KVM_EXIT_ARM_NISV;
@@ -143,7 +182,6 @@ int io_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
 			return 0;
 		}
 
-		kvm_pr_unimpl("Data abort outside memslots with no valid syndrome info\n");
 		return -ENOSYS;
 	}