On Wed, Sep 09, 2020 at 11:24:24AM +0200, David Hildenbrand wrote: > >> I am not sure an enum is going to make the existing situation less > >> messy. Sure we somehow have to distinguish boot init and runtime hotplug > >> because they have different constrains. I am arguing that a) we should > >> have a consistent way to check for those and b) we shouldn't blow up > >> easily just because sysfs infrastructure has failed to initialize. > > > > For the point a, using the enum allows to know in register_mem_sect_under_node() > > if the link operation is due to a hotplug operation or done at boot time. > > > > For the point b, one option would be ignore the link error in the case the link > > is already existing, but that BUG_ON() had the benefit to highlight the root issue. > > > > WARN_ON_ONCE() would be preferred - not crash the system but still > highlight the issue. Many many systems now run with 'panic on warn' enabled, so that wouldn't change much :( If you can warn, you can properly just print an error message and recover from the problem. thanks, greg k-h