mm/zswap: invalidate duplicate entry when !zswap_enabled

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: 42c06a0e8e ("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>
This commit is contained in:
Chengming Zhou 2024-02-08 02:32:54 +00:00 committed by Andrew Morton
parent 1eb1e98437
commit 678e54d4bb

View File

@ -1518,7 +1518,7 @@ bool zswap_store(struct folio *folio)
if (folio_test_large(folio))
return false;
if (!zswap_enabled || !tree)
if (!tree)
return false;
/*
@ -1533,6 +1533,10 @@ 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);