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Mon, 18 Nov 2024 12:20:35 +0000 Date: Mon, 18 Nov 2024 13:20:30 +0100 From: Michal Kubiak To: Breno Leitao CC: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Herbert Xu , Stephen Hemminger , , , Subject: Re: [PATCH net 2/2] netpoll: Use rcu_access_pointer() in netpoll_poll_lock Message-ID: References: <20241118-netpoll_rcu-v1-0-a1888dcb4a02@debian.org> <20241118-netpoll_rcu-v1-2-a1888dcb4a02@debian.org> Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20241118-netpoll_rcu-v1-2-a1888dcb4a02@debian.org> X-ClientProxiedBy: DUZPR01CA0039.eurprd01.prod.exchangelabs.com (2603:10a6:10:468::17) To DS0PR11MB8665.namprd11.prod.outlook.com (2603:10b6:8:1b8::6) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS0PR11MB8665:EE_|PH7PR11MB5796:EE_ X-MS-Office365-Filtering-Correlation-Id: 79765cc0-0e26-4e84-9c2d-08dd07cb67c7 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|376014|7416014|366016; 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While no RCU read lock is held > in this context, we should still use proper RCU primitives for > consistency and correctness. > > Replace the direct NULL check with rcu_access_pointer(), which is the > appropriate primitive when only checking for NULL without dereferencing > the pointer. This function provides the necessary ordering guarantees > without requiring RCU read-side protection. > > Signed-off-by: Breno Leitao > Fixes: bea3348eef27 ("[NET]: Make NAPI polling independent of struct net_device objects.") nitpick: As for the first patch - please check the tags order. Thanks, Reviewed-by: Michal Kubiak