+ mm-memory-failurec-dissolve-truncated-hugetlb-page.patch added to -mm tree

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/memory-failure.c: dissolve truncated hugetlb page
has been added to the -mm tree.  Its filename is
     mm-memory-failurec-dissolve-truncated-hugetlb-page.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-memory-failurec-dissolve-truncated-hugetlb-page.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-memory-failurec-dissolve-truncated-hugetlb-page.patch

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------------------------------------------------------
From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/memory-failure.c: dissolve truncated hugetlb page

If me_huge_page meets a truncated but not yet freed hugepage, it won't be
dissolved even if we hold the last refcnt. It's because the hugepage has
NULL page_mapping while it's not anonymous hugepage too. Thus we lose the
last chance to dissolve it into buddy to save healthy subpages. Remove
PageAnon check to handle these hugepages too.

Link: https://lkml.kernel.org/r/20220414114941.11223-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


--- a/mm/memory-failure.c~mm-memory-failurec-dissolve-truncated-hugetlb-page
+++ a/mm/memory-failure.c
@@ -1041,12 +1041,11 @@ static int me_huge_page(struct page_stat
 		res = MF_FAILED;
 		unlock_page(hpage);
 		/*
-		 * migration entry prevents later access on error anonymous
-		 * hugepage, so we can free and dissolve it into buddy to
-		 * save healthy subpages.
+		 * migration entry prevents later access on error hugepage,
+		 * so we can free and dissolve it into buddy to save healthy
+		 * subpages.
 		 */
-		if (PageAnon(hpage))
-			put_page(hpage);
+		put_page(hpage);
 		if (__page_handle_poison(p)) {
 			page_ref_inc(p);
 			res = MF_RECOVERED;
_

Patches currently in -mm which might be from linmiaohe@huawei.com are

mm-shmem-make-shmem_init-return-void.patch
mm-memcg-remove-unneeded-nr_scanned.patch
mm-mmapc-use-helper-mlock_future_check.patch
mm-mremap-use-helper-mlock_future_check.patch
mm-mremap-avoid-unneeded-do_munmap-call.patch
mm-memory-failurec-minor-cleanup-for-hwpoisonhandlable.patch
mm-memory-failurec-dissolve-truncated-hugetlb-page.patch
mm-vmscan-remove-obsolete-comment-in-get_scan_count.patch
mm-vmscan-fix-comment-for-current_may_throttle.patch
mm-z3fold-declare-z3fold_mount-with-__init.patch
mm-z3fold-remove-obsolete-comment-in-z3fold_alloc.patch
mm-z3fold-minor-clean-up-for-z3fold_free.patch
mm-z3fold-remove-unneeded-page_mapcount_reset-and-clearpageprivate.patch
mm-z3fold-remove-confusing-local-variable-l-reassignment.patch
mm-z3fold-move-decrement-of-pool-pages_nr-into-__release_z3fold_page.patch
mm-z3fold-remove-redundant-list_del_init-of-zhdr-buddy-in-z3fold_free.patch
mm-z3fold-remove-unneeded-page_headless-check-in-free_handle.patch
mm-compaction-use-helper-isolation_suitable.patch
drivers-base-nodec-fix-compaction-sysfs-file-leak.patch
mm-migration-remove-unneeded-local-variable-mapping_locked.patch
mm-migration-remove-unneeded-local-variable-page_lru.patch
mm-migration-use-helper-function-vma_lookup-in-add_page_for_migration.patch
mm-migration-use-helper-macro-min-in-do_pages_stat.patch
mm-migration-avoid-unneeded-nodemask_t-initialization.patch
mm-migration-remove-some-duplicated-codes-in-migrate_pages.patch
mm-migration-fix-potential-page-refcounts-leak-in-migrate_pages.patch
mm-migration-fix-potential-invalid-node-access-for-reclaim-based-migration.patch
mm-migration-fix-possible-do_pages_stat_array-racing-with-memory-offline.patch