On Wed, 29 May 2019, Josh Poimboeuf wrote: > hibernation_restore() is called by user space at runtime, via ioctl or > sysfs. So I think this still doesn't fix the case where you've disabled > CPUs at runtime via sysfs, and then resumed from hibernation. Or are we > declaring that this is not a supported scenario?
Yeah I personally find that scenario awkward :) Anyway, cpuhp_smt_enable() is going to online even those potentially "manually" offlined CPUs, isn't it? Are you perhaps suggesting to call enable_nonboot_cpus() instead of cpuhp_smt_enable() here to make it more explicit? > Is there are reason why maxcpus= doesn't do the CR4.MCE booted_once > dance? I am not sure whether it's really needed. My understanding is that the MCE issue happens only after primary sibling has been brought up; if that never happened, MCE wouldn't be broadcasted to that core at all in the first place. But this needs to be confirmed by Intel. -- Jiri Kosina SUSE Labs
