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b=ZOBDXX8qIyCCRdOP6tmA1KKhaSnjDoxcs35+x3T6KqIIusFXAjWJYrBMBEuco732f 2aucM9Ce26EMBbOtvMfVw5m3uXDmIwn75EbcQwOgTfa41bAvJkGvHUkD0LqeP68xaO WXvKxA1HV/VFth7JkNkkD28247+PWkJqzXGr9urxogjw99Bfe5QZqorMT5PhKjqEPm sbr0RFQP4JKb320CuP8R4H7nGOAk8d8njNUH7L5BnvlQtXPuY+B5/TUe0K1mym+3kh E77o10jT7QSqMsVnSpIkTOivSqbfl3yuMr0KsodwV68Qx86U7CG2okAg1UYJ6DuFuO /QlNjIUZ7JYxA== From: SJ Park To: Ye Liu Cc: SJ Park , Miaohe Lin , Andrew Morton , Michal Hocko , peterz@infradead.org, paulmck@kernel.org, mingo@redhat.com, rostedt@goodmis.org, jpoimboe@kernel.org, mic@digikod.net, oleg@redhat.com, tglx@kernel.org, david@kernel.org, nao.horiguchi@gmail.com, rafael@kernel.org, gnoack3000@gmail.com, ljs@kernel.org, rientjes@google.com, shakeel.butt@linux.dev, xu.xin16@zte.com.cn, chengming.zhou@linux.dev, will@kernel.org, boqun@kernel.org, frederic@kernel.org, neeraj.upadhyay@kernel.org, joelagnelf@nvidia.com, josh@joshtriplett.org, urezki@gmail.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, tony.luck@intel.com, reinette.chatre@intel.com, x86@kernel.org, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, pavel@kernel.org, lance.yang@linux.dev, mhiramat@kernel.org, pmladek@suse.com, longman@redhat.com, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, qiang.zhang@linux.dev, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, kprateek.nayak@amd.com, mark.rutland@arm.com, Dave.Martin@arm.com, james.morse@arm.com, babu.moger@amd.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rcu@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: Re: [PATCH v2 4/8] mm/memory-failure: convert process iterator to for_each_process_rculock Date: Mon, 7 Sep 2026 14:24:57 -0700 Message-ID: <20260907212457.88243-1-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260907081334.1152889-5-ye.liu@linux.dev> References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 12BE740002 X-Stat-Signature: 7rpayogtqwpa83nagr86dtwj67t1d6p1 X-Rspam-User: X-HE-Tag: 1788816307-194762 X-HE-Meta: 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 n3nEYW2P YfUpn/oSG0NzjEM9hqZ4uf0oWcRy5o0CNAzguAetcni43UnzgZrkv0M7c47ExuD5f90rV/gc4KzpziwDtaBwvKO+79inzbFu+2BNBWKK73k17XTqBZ/Wz/Z/ZilJi8hksLjhm9U0ROSEP6san9gu05y7dhP3s2P8tyKkAdouqBFBPpAPlcOGyn/lVFv9G5fgutsdTLOyFwF4snvC4BpM4ZxIFw4NuYeFJtM2gMWcsoBmDdIy3WW7iwQ3aeU7jNpq2prANyjKCvNTu82jq92gpoTXY+CgI3mhKi/ZUTwHQ4WY1gplpN8Y9QGWb3RNEDXdnGtdygeGrcX5vEmeMN/ItWzA5K4h8CVjHGPuy2q4RygHuVEWnZ700TKVYBVFC8JHUhP6oGJozIG+UAHn0FpluaVcdB+d0Wo9cN/VaXKfUk7HN4JZu0/tqk4aS1w== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, 7 Sep 2026 16:13:30 +0800 Ye Liu wrote: > From: Ye Liu > > Replace the manual rcu_read_lock()/rcu_read_unlock() pairs combined > with for_each_process() loop in mm/memory-failure.c with > for_each_process_rculock(), which scopes the RCU read lock to the > loop body via scoped_guard(rcu). > > In collect_procs_file(), the page_pgoff() call now falls outside the > RCU read-side critical section. This is safe because page_pgoff() > only reads folio->index and does not traverse any RCU-protected > structures. Thank you for clarifying :) > > Signed-off-by: Ye Liu > Acked-by: Michal Hocko > Acked-by: Miaohe Lin Reviewed-by: SJ Park Thanks, SJ [...]