]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
Docs/admin-guide/mm/damon/lru_sort: warn commit_inputs vs param updates race
authorSeongJae Park <sj@kernel.org>
Sun, 29 Mar 2026 15:30:50 +0000 (08:30 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 22 Apr 2026 11:32:19 +0000 (13:32 +0200)
commit4180aac8da7cb4c48bc8eed76c770409ccfa1ea5
tree524e4007c1e24adebbea81664566dd3106b55ca8
parentd1bb256cdbadd72b532c5eab1dee2f0775080595
Docs/admin-guide/mm/damon/lru_sort: warn commit_inputs vs param updates race

commit 0c13ed77dd2bc1c2d46db8ef27721213742cccd8 upstream.

DAMON_LRU_SORT handles commit_inputs request inside kdamond thread,
reading the module parameters.  If the user updates the module
parameters while the kdamond thread is reading those, races can happen.
To avoid this, the commit_inputs parameter shows whether it is still in
the progress, assuming users wouldn't update parameters in the middle of
the work.  Some users might ignore that.  Add a warning about the
behavior.

The issue was discovered in [1] by sashiko.

Link: https://lore.kernel.org/20260329153052.46657-3-sj@kernel.org
Link: https://lore.kernel.org/20260319161620.189392-2-objecting@objecting.org
Fixes: 6acfcd0d7524 ("Docs/admin-guide/damon: add a document for DAMON_LRU_SORT")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> # 6.0.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Documentation/admin-guide/mm/damon/lru_sort.rst