On 20/09/2019 14:54, Jan Beulich wrote: > Recent AMD processors may report up to 128 logical processors in CPUID > leaf 1. Doubling this value produces 0 (which OSes sincerely dislike), > as the respective field is only 8 bits wide. Suppress doubling the value > (and its leaf 0x80000008 counterpart) in such a case. > > Note that while there's a similar overflow in intel_xc_cpuid_policy(), > that one is being left alone for now. > > Note further that while it was considered to suppress the multiplication > by 2 altogether if the host topology already provides at least one bit > of thread ID within APIC IDs, it was decided to avoid more change here > than really needed at this point. > > Also zap leaf 4 (and at the same time leaf 2) EDX output for AMD, as it > should have been from the beginning. > > Signed-off-by: Jan Beulich <jbeul...@suse.com>
Reviewed-by: Andrew Cooper <andrew.coop...@citrix.com> I'll rebase my CPUID series over this change. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
