The patch titled Subject: mm/zswap: invalidate duplicate entry when !zswap_enabled has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-zswap-invalidate-duplicate-entry-when-zswap_enabled.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Chengming Zhou zhouchengming@bytedance.com Subject: mm/zswap: invalidate duplicate entry when !zswap_enabled Date: Thu, 8 Feb 2024 02:32:54 +0000

We have to invalidate any duplicate entry even when !zswap_enabled since zswap can be disabled anytime. If the folio store success before, then got dirtied again but zswap disabled, we won't invalidate the old duplicate entry in the zswap_store(). So later lru writeback may overwrite the new data in swapfile.

Link: https://lkml.kernel.org/r/20240208023254.3873823-1-chengming.zhou@linux.dev Fixes: 42c06a0e8ebe ("mm: kill frontswap") Signed-off-by: Chengming Zhou zhouchengming@bytedance.com Acked-by: Johannes Weiner hannes@cmpxchg.org Cc: Nhat Pham nphamcs@gmail.com Cc: Yosry Ahmed yosryahmed@google.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

mm/zswap.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/mm/zswap.c~mm-zswap-invalidate-duplicate-entry-when-zswap_enabled +++ a/mm/zswap.c @@ -1516,7 +1516,7 @@ bool zswap_store(struct folio *folio) if (folio_test_large(folio)) return false;

- if (!zswap_enabled || !tree) + if (!tree) return false;

/* @@ -1531,6 +1531,10 @@ bool zswap_store(struct folio *folio) zswap_invalidate_entry(tree, dupentry); } spin_unlock(&tree->lock); + + if (!zswap_enabled) + return false; + objcg = get_obj_cgroup_from_folio(folio); if (objcg && !obj_cgroup_may_zswap(objcg)) { memcg = get_mem_cgroup_from_objcg(objcg); _

Patches currently in -mm which might be from zhouchengming@bytedance.com are

mm-zswap-invalidate-duplicate-entry-when-zswap_enabled.patch mm-zswap-make-sure-each-swapfile-always-have-zswap-rb-tree.patch mm-zswap-split-zswap-rb-tree.patch mm-zswap-fix-race-between-lru-writeback-and-swapoff.patch mm-list_lru-remove-list_lru_putback.patch mm-zswap-add-more-comments-in-shrink_memcg_cb.patch mm-zswap-invalidate-zswap-entry-when-swap-entry-free.patch mm-zswap-stop-lru-list-shrinking-when-encounter-warm-region.patch mm-zswap-remove-duplicate_entry-debug-value.patch mm-zswap-only-support-zswap_exclusive_loads_enabled.patch mm-zswap-zswap-entry-doesnt-need-refcount-anymore.patch