+ mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch added to -mm tree

+ mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch added to -mm tree

[akpm]

The patch titled
     Subject: mm/memory_hotplug: make HWPoisoned dirty swapcache pages unmovable
has been added to the -mm tree.  Its filename is
     mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch

This patch should soon appear at
    https://ozlabs.org/~akpm/mmots/broken-out/mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch
and later at
    https://ozlabs.org/~akpm/mmotm/broken-out/mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable.patch

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------------------------------------------------------
From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/memory_hotplug: make HWPoisoned dirty swapcache pages unmovable

HWPoisoned dirty swapcache pages are kept for killing owner processes.  We
should not offline these pages or do_swap_page() would access the offline
pages and lead to bad ending.

Link: https://lkml.kernel.org/r/20210821094246.10149-4-linmiaohe@huawei.com
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 |    6 ++++++
 1 file changed, 6 insertions(+)

--- a/mm/memory_hotplug.c~mm-memory_hotplug-make-hwpoisoned-dirty-swapcache-pages-unmovable
+++ a/mm/memory_hotplug.c
@@ -1664,6 +1664,12 @@ static int scan_movable_pages(unsigned l
 		 */
 		if (PageOffline(page) && page_count(page))
 			return -EBUSY;
+		/*
+		 * HWPoisoned dirty swapcache pages are definitely unmovable
+		 * because they are kept for killing owner processes.
+		 */
+		if (PageHWPoison(page) && PageSwapCache(page))
+			return -EBUSY;
 
 		if (!PageHuge(page))
 			continue;
_

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