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[2001:470:26:54b:226:9eff:fe70:80c2]) by smtp.gmail.com with ESMTPSA id 38308e7fff4ca-34f15a5835asm32481881fa.4.2025.09.16.02.42.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Sep 2025 02:42:02 -0700 (PDT) Received: from home.paul.comp (home.paul.comp [IPv6:0:0:0:0:0:0:0:1]) by home.paul.comp (8.15.2/8.15.2/Debian-22+deb11u3) with ESMTP id 58G9fwKw021585; Tue, 16 Sep 2025 12:41:59 +0300 Received: (from paul@localhost) by home.paul.comp (8.15.2/8.15.2/Submit) id 58G9fts1021584; Tue, 16 Sep 2025 12:41:55 +0300 Date: Tue, 16 Sep 2025 12:41:55 +0300 From: Paul Fertser To: pengdonglin Cc: tj@kernel.org, tony.luck@intel.com, jani.nikula@linux.intel.com, ap420073@gmail.com, jv@jvosburgh.net, freude@linux.ibm.com, bcrl@kvack.org, trondmy@kernel.org, longman@redhat.com, kees@kernel.org, bigeasy@linutronix.de, hdanton@sina.com, paulmck@kernel.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, linux-nfs@vger.kernel.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, netdev@vger.kernel.org, intel-gfx@lists.freedesktop.org, linux-wireless@vger.kernel.org, linux-acpi@vger.kernel.org, linux-s390@vger.kernel.org, cgroups@vger.kernel.org, Samuel Mendoza-Jonas , pengdonglin Subject: Re: [PATCH v3 11/14] net: ncsi: Remove redundant rcu_read_lock/unlock() in spin_lock Message-ID: References: <20250916044735.2316171-1-dolinux.peng@gmail.com> <20250916044735.2316171-12-dolinux.peng@gmail.com> Precedence: bulk X-Mailing-List: linux-security-module@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: <20250916044735.2316171-12-dolinux.peng@gmail.com> Hello pengdonglin, Thank you for the patch, looks reasonable and justified. On Tue, Sep 16, 2025 at 12:47:32PM +0800, pengdonglin wrote: > From: pengdonglin > > Since commit a8bb74acd8efe ("rcu: Consolidate RCU-sched update-side function definitions") > there is no difference between rcu_read_lock(), rcu_read_lock_bh() and > rcu_read_lock_sched() in terms of RCU read section and the relevant grace > period. That means that spin_lock(), which implies rcu_read_lock_sched(), > also implies rcu_read_lock(). > > There is no need no explicitly start a RCU read section if one has already > been started implicitly by spin_lock(). > > Simplify the code and remove the inner rcu_read_lock() invocation. Reviewed-by: Paul Fertser