From: Miaohe Lin linmiaohe@huawei.com Subject: mm/memory_hotplug: fix potential permanent lru cache disable

If offline_pages failed after lru_cache_disable(), it forgot to do lru_cache_enable() in error path. So we would have lru cache disabled permanently in this case.

Link: https://lkml.kernel.org/r/20210821094246.10149-3-linmiaohe@huawei.com Fixes: d479960e44f2 ("mm: disable LRU pagevec during the migration temporarily") Signed-off-by: Miaohe Lin linmiaohe@huawei.com Reviewed-by: David Hildenbrand david@redhat.com Reviewed-by: Oscar Salvador osalvador@suse.de Reviewed-by: Naoya Horiguchi naoya.horiguchi@nec.com Cc: Chris Goldsworthy cgoldswo@codeaurora.org Cc: Michal Hocko mhocko@suse.com Cc: Minchan Kim minchan@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/memory_hotplug.c | 1 + 1 file changed, 1 insertion(+)

--- a/mm/memory_hotplug.c~mm-memory_hotplug-fix-potential-permanent-lru-cache-disable +++ a/mm/memory_hotplug.c @@ -1731,6 +1731,7 @@ failed_removal_isolated: undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE); memory_notify(MEM_CANCEL_OFFLINE, &arg); failed_removal_pcplists_disabled: + lru_cache_enable(); zone_pcp_enable(zone); failed_removal: pr_debug("memory offlining [mem %#010llx-%#010llx] failed due to %s\n", _