On Thu, Jul 04, 2024, Maxim Levitsky wrote: > On Fri, 2024-05-17 at 10:38 -0700, Sean Christopherson wrote: > > Extend x86's set sregs test to verify that KVM sets/clears OSXSAVE and > > OSKPKE according to CR4.XSAVE and CR4.PKE respectively. For performance > > reasons, KVM is responsible for emulating the architectural behavior of > > the OS CPUID bits tracking CR4. > > > > Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> > > --- > > tools/testing/selftests/kvm/x86_64/set_sregs_test.c | 10 ++++++++++ > > 1 file changed, 10 insertions(+) > > > > diff --git a/tools/testing/selftests/kvm/x86_64/set_sregs_test.c b/tools/testing/selftests/kvm/x86_64/set_sregs_test.c > > index 96fd690d479a..f4095a3d1278 100644 > > --- a/tools/testing/selftests/kvm/x86_64/set_sregs_test.c > > +++ b/tools/testing/selftests/kvm/x86_64/set_sregs_test.c > > @@ -85,6 +85,16 @@ static void test_cr_bits(struct kvm_vcpu *vcpu, uint64_t cr4) > > rc = _vcpu_sregs_set(vcpu, &sregs); > > TEST_ASSERT(!rc, "Failed to set supported CR4 bits (0x%lx)", cr4); > > > > + TEST_ASSERT(!!(sregs.cr4 & X86_CR4_OSXSAVE) == > > + (vcpu->cpuid && vcpu_cpuid_has(vcpu, X86_FEATURE_OSXSAVE)), > > + "KVM didn't %s OSXSAVE in CPUID as expected", > > + (sregs.cr4 & X86_CR4_OSXSAVE) ? "set" : "clear"); > > + > > + TEST_ASSERT(!!(sregs.cr4 & X86_CR4_PKE) == > > + (vcpu->cpuid && vcpu_cpuid_has(vcpu, X86_FEATURE_OSPKE)), > > + "KVM didn't %s OSPKE in CPUID as expected", > > + (sregs.cr4 & X86_CR4_PKE) ? "set" : "clear"); > > + > > Hi, > > Just for fun, why not to have a test function that toggles a CR4 bit and then > checks the corresponding CPUID bit toggles as well? This is both better > coverage wise and will remove the above code duplication. Huh, I don't know. I distinctly remember trying and failing to dedup this code, but I don't think I ever tried actively toggling each bit. I'll give that a shot.