+ mm-memory_hotplug-fix-potential-permanent-lru-cache-disable.patch added to -mm tree

+ mm-memory_hotplug-fix-potential-permanent-lru-cache-disable.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm/memory_hotplug: fix potential permanent lru cache disable
has been added to the -mm tree.  Its filename is
     mm-memory_hotplug-fix-potential-permanent-lru-cache-disable.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-fix-potential-permanent-lru-cache-disable.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-fix-potential-permanent-lru-cache-disable.patch

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------------------------------------------------------
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>
Cc: Chris Goldsworthy <cgoldswo@codeaurora.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
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
@@ -2033,6 +2033,7 @@ 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",
_

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

mm-gup-remove-set-but-unused-local-variable-major.patch
mm-gup-remove-unneed-local-variable-orig_refs.patch
mm-gup-remove-useless-bug_on-in-__get_user_pages.patch
mm-gup-fix-potential-pgmap-refcnt-leak-in-__gup_device_huge.patch
mm-gup-use-helper-page_aligned-in-populate_vma_page_range.patch
shmem-remove-unneeded-variable-ret.patch
shmem-remove-unneeded-header-file.patch
shmem-remove-unneeded-function-forward-declaration.patch
shmem-include-header-file-to-declare-swap_info.patch
mm-memcg-remove-unused-functions.patch
mm-memcg-save-some-atomic-ops-when-flush-is-already-true.patch
mm-hwpoison-remove-unneeded-variable-unmap_success.patch
mm-hwpoison-fix-potential-pte_unmap_unlock-pte-error.patch
mm-hwpoison-change-argument-struct-page-hpagep-to-hpage.patch
mm-hwpoison-fix-some-obsolete-comments.patch
mm-vmscan-remove-the-pagedirty-check-after-madv_free-pages-are-page_ref_freezed.patch
mm-vmscan-remove-misleading-setting-to-sc-priority.patch
mm-vmscan-remove-unneeded-return-value-of-kswapd_run.patch
mm-vmscan-add-else-to-remove-check_pending-label.patch
mm-vmstat-correct-some-wrong-comments.patch
mm-vmstat-simplify-the-array-size-calculation.patch
mm-vmstat-remove-unneeded-return-value.patch
mm-memory_hotplug-use-helper-zone_is_zone_device-to-simplify-the-code.patch
mm-memory_hotplug-fix-potential-permanent-lru-cache-disable.patch
mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch
mm-zsmallocc-close-race-window-between-zs_pool_dec_isolated-and-zs_unregister_migration.patch
mm-zsmallocc-combine-two-atomic-ops-in-zs_pool_dec_isolated.patch