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[173.79.60.52]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-91040646d59sm93755486d6.8.2026.09.07.08.43.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Sep 2026 08:43:50 -0700 (PDT) Date: Mon, 7 Sep 2026 11:43:47 -0400 From: Gregory Price To: Ye Liu Cc: Miaohe Lin , Andrew Morton , Ye Liu , 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, sj@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 Message-ID: References: <20260907081334.1152889-1-ye.liu@linux.dev> <20260907081334.1152889-5-ye.liu@linux.dev> Precedence: bulk X-Mailing-List: rcu@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260907081334.1152889-5-ye.liu@linux.dev> On Mon, Sep 07, 2026 at 04:13:30PM +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. > > Signed-off-by: Ye Liu > Acked-by: Michal Hocko > Acked-by: Miaohe Lin Reviewed-by: Gregory Price (Meta)