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Howlett" , Kiryl Shutsemau , Dave Chinner , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: k8i8kmbr7ccwi7ctbjdaq8facyu6sn6s X-Rspam-User: X-Rspamd-Queue-Id: DD942140006 X-Rspamd-Server: rspam12 X-HE-Tag: 1773266373-467730 X-HE-Meta: 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 mOD4LDRx bAZk2y2IN2r+ITBNAbfFZZcr1rrUAeu8dNX+M7yKgksmB7gflHc9t8SDO7eUulXCHPCqOv0DNUAnWqLKGs6yG+Z7I26XUs+/LuOJ3RvOwZExK7VKUU2LzthIvf+SuJ0GncWk/ZPZEth1Xgb7le/1Qqq169vd1yOUb+YBntasAn2qLO+bXEbcDBcqz17mObEPjMEQlMLd4TgK7GgFi2fqt4I6a++8T9fam60cOiPoQjMEDwsZvjuhhEGH/0cgvNzeJTUM7d5s9HlU03YeLtRJ5aiBhiiPv2MZrKm2cE5Xg97dWOE3vfKr6IQvKMNXQ5IZt+I1zmqwUG2LqTR0= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: > > Okay, lockdep actually does warn. rcu_read_lock_held() is explicit and > > not appeased by implicit RCU sections. > > > > Paul pointed me to rcu_read_lock_any_held(), which we could use in > > obj_cgroup_memcg() to suppress the splat and permit implicit RCU. > > > > Or we can make rcu_read_lock() explicit in the above code. > > > > Any preferences for how we want to handle this in MM code? > > I would vote for explicit rcu_read_lock() to be consistent with other places. +1