Merge branch kvm-arm64/mmio-sea into kvmarm/next

* kvm-arm64/mmio-sea:
  : Fix for SEA injection in response to MMIO
  :
  : Fix + test coverage for SEA injection in response to an unhandled MMIO
  : exit to userspace. Naturally, if userspace decides to abort an MMIO
  : instruction KVM shouldn't continue with instruction emulation...
  KVM: arm64: selftests: Add tests for MMIO external abort injection
  KVM: arm64: selftests: Convert to kernel's ESR terminology
  tools: arm64: Grab a copy of esr.h from kernel
  KVM: arm64: Don't retire aborted MMIO instruction

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

1 files changed, 30 insertions, 2 deletions

diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c
index cd6b7b83e2c3..ab365e839874 100644
--- a/arch/arm64/kvm/mmio.c
+++ b/arch/arm64/kvm/mmio.c
@@ -72,6 +72,31 @@ unsigned long kvm_mmio_read_buf(const void *buf, unsigned int len)
 	return data;
 }
 
+static bool kvm_pending_sync_exception(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):
+			return true;
+		default:
+			return false;
+		}
+	}
+}
+
 /**
  * kvm_handle_mmio_return -- Handle MMIO loads after user space emulation
  *			     or in-kernel IO emulation
@@ -84,8 +109,11 @@ 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))
+	/*
+	 * Detect if the MMIO return was already handled or if userspace aborted
+	 * the MMIO access.
+	 */
+	if (unlikely(!vcpu->mmio_needed || kvm_pending_sync_exception(vcpu)))
 		return 1;
 
 	vcpu->mmio_needed = 0;