On Fri, Feb 17, 2023 at 06:16:56AM +0000, Michael Kelley (LINUX) wrote: > Is that consistent with your thinking, or is the whole > cc_platform_has() approach problematic, including for the existing SEV > flavors and for TDX? The confidential computing attributes are, yes, features. I've been preaching since the very beginning that vTOM *is* *also* one such feature. It is a feature bit in sev_features, for chrissakes. So by that logic, those SEV-SNP HyperV guests should return true when cc_platform_has(CC_ATTR_GUEST_SEV_SNP_VTOM); is tested. But Sean doesn't like that. If the access method to the IO-APIC and vTPM are specific to the HyperV's vTOM implementation, then I don't mind if this were called cc_platform_has(CC_ATTR_GUEST_HYPERV_VTOM); Frankly, I don't see any other enlightened guest using vTOM except HyperV's but virt folks have managed to surprise me in the past too. In any case, a single flag which is specific to that guest type is fine too. It feels like we're running in circles by now... ;-\ -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette