On 04/05/21 01:22, Steve Rutherford wrote:
As far as I know, because of MSR filtering, the only "code" that needs
to be in KVM for MSR handling is a #define reserving the PV feature
number and a #define for the MSR number.
Arguably, you don't even need to add the new PV bits to the supported
cpuid, since MSR filtering is really what determines if kernel support
is present.
Not only I don't need to do that, I must not. :)
At this point I very much prefer the latter, which is basically Ashish's
earlier patch.
The minor distinction would be that if you expose the cpuid bit to the
guest you plan on intercepting the MSR with filters, and would not
need any handler code in the kernel.
Yep, and it's not a minor distinction after all (especially from the PoV
of the guy who actually ends up maintaining the code, i.e. me), so
that's what I'm going for.
Paolo
