The patch titled Subject: drivers/base/memory: add memory block to memory group after registration succeeded has been added to the -mm tree. Its filename is drivers-base-memory-add-memory-block-to-memory-group-after-registration-succeeded.patch

This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/drivers-base-memory-add-memory-blo... and later at https://ozlabs.org/~akpm/mmotm/broken-out/drivers-base-memory-add-memory-blo...

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------------------------------------------------------ From: David Hildenbrand david@redhat.com Subject: drivers/base/memory: add memory block to memory group after registration succeeded

If register_memory() fails, we freed the memory block but already added the memory block to the group list, not good. Let's defer adding the block to the memory group to after registering the memory block device.

We do handle it properly during unregister_memory(), but that's not called when the registration fails.

Link: https://lkml.kernel.org/r/20220128144540.153902-1-david@redhat.com Fixes: 028fc57a1c36 ("drivers/base/memory: introduce "memory groups" to logically group memory blocks") Signed-off-by: David Hildenbrand david@redhat.com Reviewed-by: Oscar Salvador osalvador@suse.de Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: "Rafael J. Wysocki" rafael@kernel.org Cc: Michal Hocko mhocko@suse.com Cc: stable@vger.kernel.org [5.15+] Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

drivers/base/memory.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/drivers/base/memory.c~drivers-base-memory-add-memory-block-to-memory-group-after-registration-succeeded +++ a/drivers/base/memory.c @@ -663,14 +663,16 @@ static int init_memory_block(unsigned lo mem->nr_vmemmap_pages = nr_vmemmap_pages; INIT_LIST_HEAD(&mem->group_next);

+ ret = register_memory(mem); + if (ret) + return ret; + if (group) { mem->group = group; list_add(&mem->group_next, &group->memory_blocks); }

- ret = register_memory(mem); - - return ret; + return 0; }

static int add_memory_block(unsigned long base_section_nr) _

Patches currently in -mm which might be from david@redhat.com are

mm-optimize-do_wp_page-for-exclusive-pages-in-the-swapcache.patch mm-optimize-do_wp_page-for-fresh-pages-in-local-lru-pagevecs.patch mm-slightly-clarify-ksm-logic-in-do_swap_page.patch mm-streamline-cow-logic-in-do_swap_page.patch mm-huge_memory-streamline-cow-logic-in-do_huge_pmd_wp_page.patch mm-khugepaged-remove-reuse_swap_page-usage.patch mm-swapfile-remove-stale-reuse_swap_page.patch mm-huge_memory-remove-stale-page_trans_huge_mapcount.patch mm-huge_memory-remove-stale-locking-logic-from-__split_huge_pmd.patch drivers-base-memory-add-memory-block-to-memory-group-after-registration-succeeded.patch proc-vmcore-fix-possible-deadlock-on-concurrent-mmap-and-read.patch