On Fri 24-01-20 10:04:52, Dan Williams wrote: > On Fri, Jan 24, 2020 at 4:56 AM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > > > > On Fri 10-01-20 13:27:24, Dan Williams wrote: > > > On Fri, Jan 10, 2020 at 9:42 AM David Hildenbrand <david@xxxxxxxxxx> wrote: > > [...] > > > > For your reference (roughly 5 months ago, so not that old) > > > > > > > > https://lkml.kernel.org/r/20190724143017.12841-1-david@xxxxxxxxxx > > > > > > Oh, now I see the problem. You need to add that lock so far away from > > > the __add_memory() to avoid lock inversion problems with the > > > acpi_scan_lock. The organization I was envisioning would not work > > > without deeper refactoring. > > > > Sorry to come back to this late. Has this been resolved? > > The mem_hotplug_lock lockdep splat fix in this patch has not landed. > David and I have not quite come to consensus on how to resolve online > racing removal. IIUC David wants that invalidation to be > pages_correctly_probed(), I would prefer it to be directly tied to the > object, struct memory_block, that remove_memory_block_devices() has > modified, mem->section_count = 0. I was asking about this part and I can see you have already posted a patch[1] and I do not see any reason for not merging it. [1] http://lkml.kernel.org/r/157991441887.2763922.4770790047389427325.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx -- Michal Hocko SUSE Labs
