Commit 8ae01bf6 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: selftests: Verify XCR0 can be "downgraded" and "upgraded" 



Now that KVM selftests enable all supported XCR0 features by default, add
a testcase to the XCR0 vs. CPUID test to verify that the guest can disable
everything except the legacy FPU in XCR0, and then re-enable the full
feature set, which is kinda sorta what the test did before XCR0 was setup
by default.

Reviewed-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20241003234337.273364-7-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 8b14c4d8

tools/testing/selftests/kvm/x86_64/xcr0_cpuid_test.c

+5 −0
Original line number Diff line number Diff line
@@ -79,6 +79,11 @@ static void guest_code(void) 
	ASSERT_ALL_OR_NONE_XFEATURE(supported_xcr0,

				    XFEATURE_MASK_XTILE);



	vector = xsetbv_safe(0, XFEATURE_MASK_FP);

	__GUEST_ASSERT(!vector,

		       "Expected success on XSETBV(FP), got vector '0x%x'",

		       vector);



	vector = xsetbv_safe(0, supported_xcr0);

	__GUEST_ASSERT(!vector,

		       "Expected success on XSETBV(0x%lx), got vector '0x%x'",