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> > - if (!kvm_para_available() || !kvmclock) > + if (!kvm_para_available() || !kvmclock || cc_platform_has(CC_ATTR_GUEST_SECURE_TSC)) And is setting X86_FEATURE_TSC_RELIABLE, as Dave Hansen suggests, enough to prevent usage of kvmclock? There was a discussion here: https://lore.kernel.org/lkml/20230808162320.27297-1-kirill.shutemov@linux.intel.com/ Thanks, Tom > return; > > if (kvm_para_has_feature(KVM_FEATURE_CLOCKSOURCE2)) {