On Wed 23-05-18 15:54:03, Oscar Salvador wrote: > On Thu, May 10, 2018 at 02:02:00PM +0200, Michal Hocko wrote: > > On Fri 04-05-18 17:50:51, Jonathan Cameron wrote: > > [...] > > > Exact path to the problem is as follows: > > > > > > mm/memory_hotplug.c : add_memory_resource > > > The node is not online so we enter the > > > if (new_node) twice, on the second such block there is a call to > > > link_mem_sections which calls into > > > drivers/node.c: link_mem_sections which calls > > > drivers/node.c: register_mem_sect_under_node which calls > > > get_nid_for_pfn and keeps trying until the output of that matches > > > the expected node (passed all the way down from add_memory_resource) > > > > I am sorry but I am still confused. Why don't we create sysfs files from > > __add_pages > > __add_section > > hotplug_memory_register > > register_mem_sect_under_node > > IIUC the problem is that at the point we are calling register_mem_sect_under_node(), > pages are not initialized yet. Ahh, of course. I keep forgetting the latest hotplug optimizations that we do not initialize even nid for struct pages. Which is the whole point of this patch... Sigh. I think the whole sysfs initialization needs to be refactored to be more sane. The way how we depend on things silently is just not maintainable. Thanks! -- Michal Hocko SUSE Labs
