[ sorry for a late reply too, somehow I missed this thread before ] On Tue, Jul 30, 2019 at 10:14:15AM +0200, Michal Hocko wrote: > [Sorry for a late reply] > > On Mon 15-07-19 17:55:07, Hoan Tran OS wrote: > > Hi, > > > > On 7/12/19 10:00 PM, Michal Hocko wrote: > [...] > > > Hmm, I thought this was selectable. But I am obviously wrong here. > > > Looking more closely, it seems that this is indeed only about > > > __early_pfn_to_nid and as such not something that should add a config > > > symbol. This should have been called out in the changelog though. > > > > Yes, do you have any other comments about my patch? > > Not really. Just make sure to explicitly state that > CONFIG_NODES_SPAN_OTHER_NODES is only about __early_pfn_to_nid and that > doesn't really deserve it's own config and can be pulled under NUMA. > > > > Also while at it, does HAVE_MEMBLOCK_NODE_MAP fall into a similar > > > bucket? Do we have any NUMA architecture that doesn't enable it? > > > HAVE_MEMBLOCK_NODE_MAP makes huge difference in node/zone initialization sequence so it's not only about a singe function. > > As I checked with arch Kconfig files, there are 2 architectures, riscv > > and microblaze, do not support NUMA but enable this config. My take would be that riscv will support NUMA some day. > > And 1 architecture, alpha, supports NUMA but does not enable this config. alpha's NUMA support is BROKEN for more than a decade now, I doubt it'll ever get fixed. > Care to have a look and clean this up please? > > -- > Michal Hocko > SUSE Labs > -- Sincerely yours, Mike.