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From: Muchun Song In-Reply-To: <20260204033553.50039-1-ahacigu.linux@gmail.com> Date: Wed, 4 Feb 2026 12:00:15 +0800 Cc: akpm@linux-foundation.org, david@fromorbit.com, zhengqi.arch@bytedance.com, roman.gushchin@linux.dev, linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <4FEDFC64-4EE4-4FC5-98DB-FAF9182FDFAB@linux.dev> References: <20260203073757.135088-1-ahacigu.linux@gmail.com> <20260204033553.50039-1-ahacigu.linux@gmail.com> To: Altan Hacigumus X-Migadu-Flow: FLOW_OUT X-Stat-Signature: u5yuju4fqr7ni41px5gysyb43xsnc6wo X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 4F63414000F X-HE-Tag: 1770177654-716581 X-HE-Meta: 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 PY9jXpzc 7PZ2UIjI9XKHP44yEKMoGVDD2d2FnfdlXSif/jChkZnlkVNEOGkQbHX93EoT2yGbcZp19jdI+UFHKVeGhOJ6JJnYuFQ6xmZn2byPrCqEs/YVISbN/kM2iDoAV6d9ISD9E0y8jiJ1OpaoyLNffushkhU+Fvv/tz+TczKpoMMFu2YbmXt5RnGj2X/2744MiptjwdS5IiGtdwHo9CB8qd7bCdcuT9lHd0tgAZv3ZD9rKBbO7C6Msz/HXzfnU7ZK11CZ5XokPogpdAQFNrzyqSurffDRgEqo3yQPweyMetw8YdEM0TtXEhh0d/GwG+TDvfjXZie8RFcMeLTVbYPlOmLDfTfMW+LS+gdokpAw0rTVm0ZdhBDmU0VG5Tk6aVJB3ZbnFstJg5zlEMU1TgbohAFxkVFzroqSqA5v/2xWii+OMEXBiOD66xjafBZaA2d9L3RNI0F4s X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > On Feb 4, 2026, at 11:35, Altan Hacigumus = wrote: >=20 > 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. >=20 > Add the missing shrinker_put(). >=20 > Also, since memcg_kmem_online() and shrinker flags cannot change > dynamically, remove the shrinker from the bitmap to avoid unnecessary > future scans. >=20 > Fixes: 50d09da8e119 ("mm: shrinker: make memcg slab shrink lockless") > Suggested-by: Qi Zheng > Acked-by: Qi Zheng > Link: = https://lore.kernel.org/r/20260203073757.135088-1-ahacigu.linux@gmail.com > Signed-off-by: Altan Hacigumus Reviewed-by: Muchun Song