linux-kernel - [PATCH 11/11] KVM: selftests: Ensure KVM supports AVX for SEV-ES VMSA FPU test

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Message-ID: <20241003234337.273364-12-seanjc@google.com>
Date: Thu,  3 Oct 2024 16:43:37 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Vitaly Kuznetsov <vkuznets@...hat.com>
Subject: [PATCH 11/11] KVM: selftests: Ensure KVM supports AVX for SEV-ES VMSA
 FPU test

Verify that KVM's supported XCR0 includes AVX (and earlier features) when
running the SEV-ES VMSA XSAVE test.  In practice, the issue will likely
never pop up, since KVM support for AVX predates KVM support for SEV-ES,
but checking for KVM support makes the requirement more obvious.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 tools/testing/selftests/kvm/x86_64/sev_smoke_test.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
index 965fc362dee3..ae77698e6e97 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_smoke_test.c
@@ -181,6 +181,8 @@ static void test_sev_es_shutdown(void)
 
 int main(int argc, char *argv[])
 {
+	const u64 xf_mask = XFEATURE_MASK_X87_AVX;
+
 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SEV));
 
 	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
@@ -193,7 +195,7 @@ int main(int argc, char *argv[])
 		test_sev_es_shutdown();
 
 		if (kvm_has_cap(KVM_CAP_XCRS) &&
-		    (xgetbv(0) & XFEATURE_MASK_X87_AVX) == XFEATURE_MASK_X87_AVX) {
+		    (xgetbv(0) & kvm_cpu_supported_xcr0() & xf_mask) == xf_mask) {
 			test_sync_vmsa(0);
 			test_sync_vmsa(SEV_POLICY_NO_DBG);
 		}
-- 
2.47.0.rc0.187.ge670bccf7e-goog