[PATCH 08/13] KVM: arm64: selftests: Select SMCCC conduit based on current EL

Oliver Upton
2025-09-17T21:21:40Z

HVCs are taken within the VM when EL2 is in use. Ensure tests use the
SMC instruction when running at EL2 to interact with the host.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
---
tools/testing/selftests/kvm/arm64/hypercalls.c | 2 +-
tools/testing/selftests/kvm/arm64/kvm-uuid.c | 2 +-
tools/testing/selftests/kvm/arm64/psci_test.c | 10 +++++-----
.../testing/selftests/kvm/include/arm64/processor.h | 13 +++++++++++++
tools/testing/selftests/kvm/steal_time.c | 2 +-
5 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/kvm/arm64/hypercalls.c b/tools/testing/selftests/kvm/arm64/hypercalls.c
index 44cfcf8a7f46..bf038a0371f4 100644
--- a/tools/testing/selftests/kvm/arm64/hypercalls.c
+++ b/tools/testing/selftests/kvm/arm64/hypercalls.c
@@ -108,7 +108,7 @@ static void guest_test_hvc(const struct test_hvc_info *hc_info)

for (i = 0; i < hvc_info_arr_sz; i++, hc_info++) {
memset(&res, 0, sizeof(res));
- smccc_hvc(hc_info->func_id, hc_info->arg1, 0, 0, 0, 0, 0, 0, &res);
+ do_smccc(hc_info->func_id, hc_info->arg1, 0, 0, 0, 0, 0, 0, &res);

switch (stage) {
case TEST_STAGE_HVC_IFACE_FEAT_DISABLED:
diff --git a/tools/testing/selftests/kvm/arm64/kvm-uuid.c b/tools/testing/selftests/kvm/arm64/kvm-uuid.c
index af9581b860f1..b5be9133535a 100644
--- a/tools/testing/selftests/kvm/arm64/kvm-uuid.c
+++ b/tools/testing/selftests/kvm/arm64/kvm-uuid.c
@@ -25,7 +25,7 @@ static void guest_code(void)
{
struct arm_smccc_res res = {};

- smccc_hvc(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, 0, 0, 0, 0, 0, 0, 0, &res);
+ do_smccc(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, 0, 0, 0, 0, 0, 0, 0, &res);

__GUEST_ASSERT(res.a0 == ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0 &&
res.a1 == ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1 &&
diff --git a/tools/testing/selftests/kvm/arm64/psci_test.c b/tools/testing/selftests/kvm/arm64/psci_test.c
index 0d4680da66d1..98e49f710aef 100644
--- a/tools/testing/selftests/kvm/arm64/psci_test.c
+++ b/tools/testing/selftests/kvm/arm64/psci_test.c
@@ -27,7 +27,7 @@ static uint64_t psci_cpu_on(uint64_t target_cpu, uint64_t entry_addr,
{
struct arm_smccc_res res;

- smccc_hvc(PSCI_0_2_FN64_CPU_ON, target_cpu, entry_addr, context_id,
+ do_smccc(PSCI_0_2_FN64_CPU_ON, target_cpu, entry_addr, context_id,
0, 0, 0, 0, &res);

return res.a0;
@@ -38,7 +38,7 @@ static uint64_t psci_affinity_info(uint64_t target_affinity,
{
struct arm_smccc_res res;

- smccc_hvc(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity, lowest_affinity_level,
+ do_smccc(PSCI_0_2_FN64_AFFINITY_INFO, target_affinity, lowest_affinity_level,
0, 0, 0, 0, 0, &res);

return res.a0;
@@ -48,7 +48,7 @@ static uint64_t psci_system_suspend(uint64_t entry_addr, uint64_t context_id)
{
struct arm_smccc_res res;

- smccc_hvc(PSCI_1_0_FN64_SYSTEM_SUSPEND, entry_addr, context_id,
+ do_smccc(PSCI_1_0_FN64_SYSTEM_SUSPEND, entry_addr, context_id,
0, 0, 0, 0, 0, &res);

return res.a0;
@@ -58,7 +58,7 @@ static uint64_t psci_system_off2(uint64_t type, uint64_t cookie)
{
struct arm_smccc_res res;

- smccc_hvc(PSCI_1_3_FN64_SYSTEM_OFF2, type, cookie, 0, 0, 0, 0, 0, &res);
+ do_smccc(PSCI_1_3_FN64_SYSTEM_OFF2, type, cookie, 0, 0, 0, 0, 0, &res);

return res.a0;
}
@@ -67,7 +67,7 @@ static uint64_t psci_features(uint32_t func_id)
{
struct arm_smccc_res res;

- smccc_hvc(PSCI_1_0_FN_PSCI_FEATURES, func_id, 0, 0, 0, 0, 0, 0, &res);
+ do_smccc(PSCI_1_0_FN_PSCI_FEATURES, func_id, 0, 0, 0, 0, 0, 0, &res);

return res.a0;
}
diff --git a/tools/testing/selftests/kvm/include/arm64/processor.h b/tools/testing/selftests/kvm/include/arm64/processor.h
index 87f50efed720..f037c1bb8e63 100644
--- a/tools/testing/selftests/kvm/include/arm64/processor.h
+++ b/tools/testing/selftests/kvm/include/arm64/processor.h
@@ -359,4 +359,17 @@ static __always_inline u64 ctxt_reg_alias(struct kvm_vcpu *vcpu, u32 encoding)

void kvm_get_default_vcpu_target(struct kvm_vm *vm, struct kvm_vcpu_init *init);

+static inline unsigned int get_current_el(void)
+{
+ return (read_sysreg(CurrentEL) >> 2) & 0x3;
+}
+
+#define do_smccc(...) \
+do { \
+ if (get_current_el() == 2) \
+ smccc_smc(__VA_ARGS__); \
+ else \
+ smccc_hvc(__VA_ARGS__); \
+} while (0)
+
#endif /* SELFTEST_KVM_PROCESSOR_H */
diff --git a/tools/testing/selftests/kvm/steal_time.c b/tools/testing/selftests/kvm/steal_time.c
index cce2520af720..8edc1fca345b 100644
--- a/tools/testing/selftests/kvm/steal_time.c
+++ b/tools/testing/selftests/kvm/steal_time.c
@@ -118,7 +118,7 @@ static int64_t smccc(uint32_t func, uint64_t arg)
{
struct arm_smccc_res res;

- smccc_hvc(func, arg, 0, 0, 0, 0, 0, 0, &res);
+ do_smccc(func, arg, 0, 0, 0, 0, 0, 0, &res);
return res.a0;
}

--
2.47.3