diff options
| author | Altan Hacigumus <ahacigu.linux@gmail.com> | 2026-02-04 06:35:53 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2026-03-25 00:38:26 +0300 |
| commit | 260d70819c37cf59383286f8dc6566eaa32776bb (patch) | |
| tree | 7a6e276552080e0dcc7976e554049506ae370628 | |
| parent | b8a4b088381875ff1a93c0c2d5a926b30b1bfe31 (diff) | |
| download | linux-260d70819c37cf59383286f8dc6566eaa32776bb.tar.xz | |
mm/shrinker: fix refcount leak in shrink_slab_memcg()
When kmem is disabled for memcg, slab-backed shrinkers are skipped.
However, shrink_slab_memcg() doesn't drop the reference acquired via
shrinker_try_get() before continuing.
Add the missing shrinker_put().
Also, since memcg_kmem_online() and shrinker flags cannot change
dynamically, remove the shrinker from the bitmap to avoid unnecessary
future scans.
Link: https://lkml.kernel.org/r/20260204033553.50039-1-ahacigu.linux@gmail.com
Fixes: 50d09da8e119 ("mm: shrinker: make memcg slab shrink lockless")
Signed-off-by: Altan Hacigumus <ahacigu.linux@gmail.com>
Acked-by: Qi Zheng <zhengqi.arch@bytedance.com>
Link: https://lore.kernel.org/r/20260203073757.135088-1-ahacigu.linux@gmail.com
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/shrinker.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/mm/shrinker.c b/mm/shrinker.c index 7b61fc0ee78f..94646ee0af63 100644 --- a/mm/shrinker.c +++ b/mm/shrinker.c @@ -544,8 +544,11 @@ again: /* Call non-slab shrinkers even though kmem is disabled */ if (!memcg_kmem_online() && - !(shrinker->flags & SHRINKER_NONSLAB)) + !(shrinker->flags & SHRINKER_NONSLAB)) { + clear_bit(offset, unit->map); + shrinker_put(shrinker); continue; + } ret = do_shrink_slab(&sc, shrinker, priority); if (ret == SHRINK_EMPTY) { |