This is a note to let you know that I've just added the patch titled
mm/zswap: invalidate duplicate entry when !zswap_enabled
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mm-zswap-invalidate-duplicate-entry-when-zswap_enabled.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 678e54d4bb9a4822f8ae99690ac131c5d490cdb1 Mon Sep 17 00:00:00 2001
From: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Date: Thu, 8 Feb 2024 02:32:54 +0000
Subject: mm/zswap: invalidate duplicate entry when !zswap_enabled
From: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
commit 678e54d4bb9a4822f8ae99690ac131c5d490cdb1 upstream.
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@xxxxxxxxx
Fixes: 42c06a0e8ebe ("mm: kill frontswap")
Signed-off-by: Chengming Zhou <zhouchengming@xxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Nhat Pham <nphamcs@xxxxxxxxx>
Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
mm/zswap.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -1215,7 +1215,7 @@ bool zswap_store(struct folio *folio)
if (folio_test_large(folio))
return false;
- if (!zswap_enabled || !tree)
+ if (!tree)
return false;
/*
@@ -1231,6 +1231,9 @@ bool zswap_store(struct folio *folio)
}
spin_unlock(&tree->lock);
+ if (!zswap_enabled)
+ return false;
+
/*
* XXX: zswap reclaim does not work with cgroups yet. Without a
* cgroup-aware entry LRU, we will push out entries system-wide based on
Patches currently in stable-queue which might be from zhouchengming@xxxxxxxxxxxxx are
queue-6.6/mm-zswap-fix-missing-folio-cleanup-in-writeback-race-path.patch
queue-6.6/mm-zswap-invalidate-duplicate-entry-when-zswap_enabled.patch
