KVM: arm64: selftests: Test ESR propagation for vSError injection

Ensure that vSErrors taken in the guest have an appropriate ESR_ELx
value for the expected exception. Additionally, switch the EASE test to
install the SEA handler at the SError offset, as the ESR is still
expected to match an SEA in that case.

Link: https://lore.kernel.org/r/20250708230632.1954240-3-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

1 files changed, 30 insertions, 2 deletions

diff --git a/tools/testing/selftests/kvm/arm64/external_aborts.c b/tools/testing/selftests/kvm/arm64/external_aborts.c
index ec7e30776a0e..062bf84cced1 100644
--- a/tools/testing/selftests/kvm/arm64/external_aborts.c
+++ b/tools/testing/selftests/kvm/arm64/external_aborts.c
@@ -7,7 +7,8 @@
 #include "processor.h"
 #include "test_util.h"
 
-#define MMIO_ADDR	0x8000000ULL
+#define MMIO_ADDR		0x8000000ULL
+#define EXPECTED_SERROR_ISS	(ESR_ELx_ISV | 0x1d1ed)
 
 static u64 expected_abort_pc;
 
@@ -49,11 +50,28 @@ static void vcpu_inject_sea(struct kvm_vcpu *vcpu)
 	vcpu_events_set(vcpu, &events);
 }
 
+static bool vcpu_has_ras(struct kvm_vcpu *vcpu)
+{
+	u64 pfr0 = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1));
+
+	return SYS_FIELD_GET(ID_AA64PFR0_EL1, RAS, pfr0);
+}
+
+static bool guest_has_ras(void)
+{
+	return SYS_FIELD_GET(ID_AA64PFR0_EL1, RAS, read_sysreg(id_aa64pfr0_el1));
+}
+
 static void vcpu_inject_serror(struct kvm_vcpu *vcpu)
 {
 	struct kvm_vcpu_events events = {};
 
 	events.exception.serror_pending = true;
+	if (vcpu_has_ras(vcpu)) {
+		events.exception.serror_has_esr = true;
+		events.exception.serror_esr = EXPECTED_SERROR_ISS;
+	}
+
 	vcpu_events_set(vcpu, &events);
 }
 
@@ -199,6 +217,12 @@ static void test_serror_masked(void)
 
 static void expect_serror_handler(struct ex_regs *regs)
 {
+	u64 esr = read_sysreg(esr_el1);
+
+	GUEST_ASSERT_EQ(ESR_ELx_EC(esr), ESR_ELx_EC_SERROR);
+	if (guest_has_ras())
+		GUEST_ASSERT_EQ(ESR_ELx_ISS(esr), EXPECTED_SERROR_ISS);
+
 	GUEST_DONE();
 }
 
@@ -277,7 +301,11 @@ static void test_mmio_ease(void)
 		return;
 	}
 
-	vm_install_exception_handler(vm, VECTOR_ERROR_CURRENT, expect_serror_handler);
+	/*
+	 * SCTLR2_ELx.EASE changes the exception vector to the SError vector but
+	 * doesn't further modify the exception context (e.g. ESR_ELx, FAR_ELx).
+	 */
+	vm_install_exception_handler(vm, VECTOR_ERROR_CURRENT, expect_sea_handler);
 
 	vcpu_run(vcpu);
 	TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_MMIO);