On Wed, Apr 21, 2021 at 10:22:39AM +0000, Wei Liu wrote: > On Tue, Apr 13, 2021 at 04:01:33PM +0200, Roger Pau Monne wrote: > > Introduce a helper to obtain a compatible cpu policy based on two > > input cpu policies. Currently this is done by and'ing all CPUID leaves > > and MSR entries, except for MSR_ARCH_CAPABILITIES which has the RSBA > > bit or'ed. > > > > I thought canonical source for compatibility was to be put into the > hypervisor, thus all this functionality would be in the hypervisor. Am I > misremembering?
Andrew said something similar on v1, but I'm not able to figure how this would be used by the hypervisor. It's my understating that the toolstack will attempt to generate a CPU policy and forward it to the hypervisor, which will either accept or reject it based on the capabilities of the system. I'm not sure I see why we would need to give the hypervisor two policies in order to generate a resulting compatible one - it should all be done by the toolstack AFAICT. If there's a use case for this being in the hypervisor I'm happy to add it there, but so far I haven't been able to come up with one myself, and hence I don't see the need to make the code available. Thanks, Roger.
