On Mon, Aug 07, 2023 at 03:17:18PM +0200, Jan Beulich wrote: > On 07.08.2023 14:55, Simon Gaiser wrote: > > Jan Beulich: > >> On 07.08.2023 11:38, Simon Gaiser wrote: > >>> It seems some firmwares put dummy entries in the ACPI MADT table for non > >>> existing processors. On my NUC11TNHi5 those have the invalid APIC ID > >>> 0xff. Linux already has code to handle those cases both in > >>> acpi_parse_lapic [1] as well as in acpi_parse_x2apic [2]. So add the > >>> same check to Xen. > >> > >> I'm afraid it doesn't become clear to me what problem you're trying to > >> solve. > > > > I want Xen to not think there are possible CPUs that actually never can > > be there. > > Did you try using "maxcpus=" on the command line? If that doesn't work > well enough (perhaps because of causing undesirable log messages), maybe > we need some way to say "no CPU hotplug" on the command line.
A Kconfig option to disable CPU hotplug at build time would also be interesting IMO. Thanks, Roger.
