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(p200300ea8f3a0400c49ced9196e5222b.dip0.t-ipconnect.de. [2003:ea:8f3a:400:c49c:ed91:96e5:222b]) by smtp.googlemail.com with ESMTPSA id ffacd0b85a97d-3a1f58ebd43sm5947801f8f.37.2025.05.10.01.46.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 10 May 2025 01:46:16 -0700 (PDT) Message-ID: <4f405d9b-460c-49f7-91b2-d147d9818369@gmail.com> Date: Sat, 10 May 2025 10:46:32 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-US To: Andrew Morton , Greg Kroah-Hartman , Ingo Molnar Cc: Linux Kernel Mailing List From: Heiner Kallweit Subject: Documentation of locking needs when working with lists? 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My case: I have a list where the only operation is adding entries. It's clear that adding entries has to be serialized. Question is whether a list_for_each_entry is safe lock-less. Looking at the code I *think* it's safe, under the precondition that reading/writing pointers is atomic. Any hint or documentation link would be appreciated. Thanks!