On Thu, May 07, 2020 at 01:13:21AM +0200, Tobias Nygren wrote: > Fetch sysctl machdep.cpu0.cpu_id (see usr.sbin/cpuctl/arch/aarch64.c) > Then test the ID_AA64ISAR0_EL1 register bits 23:20 for the value 0b0010. That doesn't sound safe (what if cpu0 and cpu$N disagree?) Martin