On 10.02.2021 18:00, Andrew Cooper wrote: > On 10/02/2021 16:48, Jan Beulich wrote: >> The address of this page is used by the CPU only to recognize when to >> instead access the virtual APIC page instead. No accesses would ever go >> to this page. It only needs to be present in the (CPU) page tables so >> that address translation will produce its address as result for >> respective accesses. >> >> By making this page global, we also eliminate the need to refcount it, >> or to assign it to any domain in the first place. >> >> Signed-off-by: Jan Beulich <jbeul...@suse.com> > > How certain are you about this? > > It's definitely not true on AMD's AVIC - writes very definitely end up > in the backing page if they miss the APIC registers.
Doesn't this require a per-vCPU page then anyway? With a per-domain one things can't work correctly in the case you describe. Jan
