[PATCH v2 4/4] KVM: selftests: Add a smoke test support for RAPL_DIS

Tycho Andersen
2026-04-27T20:50:51Z

If the hardware supports the RAPL_DIS policy bit and the ccp has been
loaded with the RAPL_DIS bit set, make sure a VM can
actually start using it.

Signed-off-by: Tycho Andersen (AMD) <tycho@kernel.org>
---
tools/testing/selftests/kvm/include/x86/sev.h | 1 +
.../selftests/kvm/x86/sev_smoke_test.c | 24 ++++++++++++++++++-
2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/include/x86/sev.h b/tools/testing/selftests/kvm/include/x86/sev.h
index 1af44c151d60..2bbac9cd192a 100644
--- a/tools/testing/selftests/kvm/include/x86/sev.h
+++ b/tools/testing/selftests/kvm/include/x86/sev.h
@@ -28,6 +28,7 @@ enum sev_guest_state {
#define SNP_POLICY_SMT (1ULL << 16)
#define SNP_POLICY_RSVD_MBO (1ULL << 17)
#define SNP_POLICY_DBG (1ULL << 19)
+#define SNP_POLICY_RAPL_DIS (1ULL << 23)

#define GHCB_MSR_TERM_REQ 0x100

diff --git a/tools/testing/selftests/kvm/x86/sev_smoke_test.c b/tools/testing/selftests/kvm/x86/sev_smoke_test.c
index 1a49ee391586..15c848749de6 100644
--- a/tools/testing/selftests/kvm/x86/sev_smoke_test.c
+++ b/tools/testing/selftests/kvm/x86/sev_smoke_test.c
@@ -243,6 +243,18 @@ static void test_sev_smoke(void *guest, u32 type, u64 policy)
}
}

+static u64 supported_policy_mask(void)
+{
+ int kvm_fd = open_kvm_dev_path_or_exit();
+ u64 policy_mask = 0;
+
+ kvm_device_attr_get(kvm_fd, KVM_X86_GRP_SEV,
+ KVM_X86_SNP_POLICY_BITS,
+ &policy_mask);
+ close(kvm_fd);
+ return policy_mask;
+}
+
int main(int argc, char *argv[])
{
TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SEV));
@@ -252,8 +264,18 @@ int main(int argc, char *argv[])
if (kvm_cpu_has(X86_FEATURE_SEV_ES))
test_sev_smoke(guest_sev_es_code, KVM_X86_SEV_ES_VM, SEV_POLICY_ES);

- if (kvm_cpu_has(X86_FEATURE_SEV_SNP))
+ if (kvm_cpu_has(X86_FEATURE_SEV_SNP)) {
+ u64 supported_policy = supported_policy_mask();
+
test_sev_smoke(guest_snp_code, KVM_X86_SNP_VM, snp_default_policy());

+ if (supported_policy & SNP_POLICY_RAPL_DIS &&
+ kvm_get_module_param_bool("kvm_amd", "rapl_disable")) {
+ u64 policy = snp_default_policy() | SNP_POLICY_RAPL_DIS;
+
+ test_sev_smoke(guest_snp_code, KVM_X86_SNP_VM, policy);
+ }
+ }
+
return 0;
}
--
2.53.0