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Miller" , linux-kernel@vger.kernel.org, Eric Dumazet , Vladimir Oltean References: <20220816163701.1578850-1-sean.anderson@seco.com> <20220818102443.4c7c50e8@kernel.org> From: Sean Anderson Message-ID: Date: Thu, 18 Aug 2022 13:32:36 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 In-Reply-To: <20220818102443.4c7c50e8@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BL1PR13CA0013.namprd13.prod.outlook.com (2603:10b6:208:256::18) To DB7PR03MB4972.eurprd03.prod.outlook.com (2603:10a6:10:7d::22) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 107ac566-da9d-4d36-ab90-08da813fa682 X-MS-TrafficTypeDiagnostic: VI1PR0301MB2495:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DB7PR03MB4972.eurprd03.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230016)(396003)(376002)(346002)(136003)(39840400004)(366004)(52116002)(54906003)(6486002)(53546011)(6916009)(5660300002)(316002)(31696002)(66476007)(66556008)(31686004)(66946007)(8676002)(7416002)(44832011)(86362001)(8936002)(4326008)(36756003)(478600001)(83380400001)(2616005)(2906002)(41300700001)(6506007)(6512007)(26005)(186003)(6666004)(38100700002)(38350700002)(45980500001)(43740500002);DIR:OUT;SFP:1101; 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It's also >> possible that the memory has been reallocated if sufficient time passes >> between when the phy is detached and when the netdev touches the phy >> (which could result in silent memory corruption). Add a warning at the >> source of the problem. A future patch could make this more robust by >> calling dev_close. > > Hm, so we're adding the warning to get more detailed reports "from the > field"? Guess we've all done that, so fair. My suspicion is that this case never occurs, since users don't expect to be able to remove the phy while the interface is running (and so don't attempt it). If we do end up getting reports of this bug, then we will need to create a more robust fix. My intention is to take the same strategy for PCS devices as whatever we do here, since the issue is analogous. --Sean