On Sun, Nov 29, 2020 at 12:04:04AM -0800, I wrote: > On Sun, Nov 29, 2020 at 06:36:17AM +0000, Mike wrote: > > And what are you going to return for the other leaf nodes now that > > you are claiming a CPUID level of 0x15, on CPUs that are less than > > that? > > > > Eg, if your host supports level 0xb (11), what happens in your diff > > if the guest VM requests CPUID leaf node 0x0c (12)? > > > > It seems you are only handing the single 0x15 case. > > That is true. > > We need to note though that the current situation is not correct either. > [...] > What do you suggest?
Two ideas spring to mind for how to resolve this: (a) Figure out from Intel's documentation for each leaf (and sub-leaf) what response is correct and does not require us to emulate too much. (b) Add a sysctl knob that controls whether we even announce a higher cpu level to the guest than what the host supports, so that we do not expose people to the incorrectness by default. What do you think? jh
