On Tue, May 30, 2023, Jinrong Liang wrote:
> +static void test_fixed_counters_setup(struct kvm_vcpu *vcpu, uint8_t edx_fix_num,
> + uint32_t fixed_bitmask, bool expected)
> +{
> + struct kvm_cpuid_entry2 *entry;
> + uint8_t max_fixed_num = X86_INTEL_MAX_FIXED_CTR_NUM;
> + uint64_t supported_bitmask = 0;
> + uint64_t msr_val;
> + unsigned int i;
> +
> + entry = vcpu_get_cpuid_entry(vcpu, 0xa);
> + entry->ecx = fixed_bitmask;
> + entry->edx = (entry->edx & ~FIXED_CTR_NUM_MASK) | edx_fix_num;
> + vcpu_set_cpuid(vcpu);
> +
> + for (i = 0; i < max_fixed_num; i++) {
> + if (entry->ecx & BIT_ULL(i) ||
> + ((entry->edx & FIXED_CTR_NUM_MASK) > i))
> + supported_bitmask |= BIT_ULL(i);
> + }
> +
> + vcpu_args_set(vcpu, 2, supported_bitmask, max_fixed_num);
All of this can be queried from the guest, no? Then you also verify that KVM is
passing in the correct CPUID info too.
> + while (run_vcpu(vcpu, &msr_val) != UCALL_DONE)
> + TEST_ASSERT(!!msr_val == expected,
> + "Unexpected when testing fixed counter.");
ASSERT_EQ()
