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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? No that wasn't sufficient. kvmclock was always selected before SecureTSC even when X86_FEATURE_TSC_RELIABLE was selected. > > There was a discussion here: >  https://lore.kernel.org/lkml/20230808162320.27297-1-kirill.shutemov@linux.intel.com/ > > Thanks, > Tom Regards Nikunj