On Mon, 23 Sep 2019 11:16:38 +0530 Anshuman Khandual <anshuman.khandual@xxxxxxx> wrote: > > > On 09/16/2019 11:17 AM, Anshuman Khandual wrote: > > In add_memory_resource() the memory range to be hot added first gets into > > the memblock via memblock_add() before arch_add_memory() is called on it. > > Reverse sequence should be followed during memory hot removal which already > > is being followed in add_memory_resource() error path. This now ensures > > required re-order between memblock_[free|remove]() and arch_remove_memory() > > during memory hot-remove. > > > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Cc: Oscar Salvador <osalvador@xxxxxxx> > > Cc: Michal Hocko <mhocko@xxxxxxxx> > > Cc: David Hildenbrand <david@xxxxxxxxxx> > > Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> > > Cc: Dan Williams <dan.j.williams@xxxxxxxxx> > > Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> > > --- > > Original patch https://lkml.org/lkml/2019/9/3/327 > > > > Memory hot remove now works on arm64 without this because a recent commit > > 60bb462fc7ad ("drivers/base/node.c: simplify unregister_memory_block_under_nodes()"). > > > > David mentioned that re-ordering should still make sense for consistency > > purpose (removing stuff in the reverse order they were added). This patch > > is now detached from arm64 hot-remove series. > > > > https://lkml.org/lkml/2019/9/3/326 > > ... > > Hello Andrew, > > Any feedbacks on this, does it look okay ? > Well. I'd parked this for 5.4-rc1 processing because it looked like a cleanup. But waaaay down below the ^---$ line I see "Memory hot remove now works on arm64". Am I correct in believing that 60bb462fc7ad broke arm64 mem hot remove? And that this patch fixes a serious regression? If so, that should have been right there in the patch title and changelog!
