From: Ma Wupeng <mawupeng1@xxxxxxxxxx> Hi maintainers: Our test find a memleak in init_memory_block, it is clear that mem is never been released due to wrong refcount. Commit 08b3acd7a68f ("mm/memory_hotplug: Introduce offline_and_remove_memory()") failed to dec refcount after find_memory_block which fail to dec refcount to zero in remove memory causing the leak. Commit 8dc4bb58a146 ("mm/memory_hotplug: extend offline_and_remove_memory() to handle more than one memory block") introduce walk_memory_blocks to replace find_memory_block which dec refcount by calling put_device after find_memory_block_by_id. In the way, the memleak is fixed. Here is the simplified calltrace: kmem_cache_alloc_trace+0x664/0xed0 init_memory_block+0x8c/0x170 create_memory_block_devices+0xa4/0x150 add_memory_resource+0x188/0x530 __add_memory+0x78/0x104 add_memory+0x6c/0xb0 David Hildenbrand (1): mm/memory_hotplug: extend offline_and_remove_memory() to handle more than one memory block mm/memory_hotplug.c | 105 +++++++++++++++++++++++++++++++++++++------- 1 file changed, 89 insertions(+), 16 deletions(-) -- 2.25.1