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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?JEqTx3+f3PbyvrIrWeedqkEw3Kx3bMPUV79ixN/K29BvjhIxZzo+h1+eiEgy?= =?us-ascii?Q?mE82F9v4/vKfVP5OgRNH81uiJ9LR6p2Hz9frcdFnjjDq0ap9MyPGTh0LnqG9?= =?us-ascii?Q?HAOLauFL0zTAILUUneLm9zlsbpATA2IApJpsm/I4y+Kds1Rkq2ErnFWKaB47?= =?us-ascii?Q?TIrUlhZeiopxqB/b1reKAjYXRgBD2OfeXaTZs19V7nMMddJs1uDk+XRqGqKp?= =?us-ascii?Q?/+LZoxQcMk26V9g7U/rIBlbqS21/fWzpU0CBni5lYpJq9ogIqWzXig86rl9S?= =?us-ascii?Q?H1hf9ZaPq0T4rbJfpf6dcwM/OkOlaJ3jERqoPk+tM4E1TkvH73QCZJvi0Nv0?= =?us-ascii?Q?wX/PRJjUfehsWGGhSXTs5INA/GqKCe+JNvBgr/5T8/BTSj7pyeJLBEc2BiYo?= =?us-ascii?Q?HxkPT5wa4TxrY/UC5aR08y43LlBENgpA+N2AMpgJByBbaUyI2zthQNSTdn2Q?= =?us-ascii?Q?pKj3xoxpK9xTcqZ5jK/O+J4geWAVVA1JrZhEupjPeJRp4n0tA0Bd/IG6OHRg?= =?us-ascii?Q?bxQFyhx7WXWVdrsg4vHy4mhk45WSFsLsssUn47I1AA/l2ms6kkLOQSpZpiWx?= =?us-ascii?Q?LFi/tunZmfpD4TXqJaaNhxYCrU4I/Fa0XO+H99gZzkLqfPiDP3L45LktimFA?= =?us-ascii?Q?dnpY56wWlm7ak2/nunb+Asr9alGYrjufRLPsgEqZw5wfesclvV6X5J2joqJG?= =?us-ascii?Q?EONUVcJF7wvXD5TYmNVkGh/uZbXF+mdpTXQyg4UZGqDCnUV792kIK03z0Bfa?= =?us-ascii?Q?rviFe6P4hmqHkyZ0oAeAWYYN2cgUx+nI9NogK2aYVMa3wI2nj/n9GQ9VI+8X?= =?us-ascii?Q?mqibRhclsrysLvO8D2u4HnGQRYXotPvKjti6e4iwKdH0BhroIsFWBftv5XuB?= =?us-ascii?Q?x9vRSvbSTHF++TXLcRcdVvuR737nEfa7IIjt6xO2CK7IkdcRPuu2MvIdo8bV?= =?us-ascii?Q?IcteKzCDEzETlQO2szBIQGUqtjHcsW1vaHA8CL7BzwW/hfTXF1MDkJtyj9S8?= =?us-ascii?Q?Y0JgxhGd8K4KtZrkleFs69UpcrglKwa3tqR1+RDoqLDtTFPeNNWdK3DBGRiE?= =?us-ascii?Q?EorqyvHsaChoi1pTwqCnX1/dWKv/7PptW5rqxTuF7Xc1KzMu91QjBc3+GrTH?= =?us-ascii?Q?5N4Ed3iiUVO6pqBp4tUabRUl6EwFRSGvJwVZPqPMV3iTwMmyoWqbyxnz8OjY?= =?us-ascii?Q?QpoKL5m0a8qzSX2nEW1/veNHYZLdYBrZR7rLBvVvEkVGIeguj7T+na/tC5PP?= =?us-ascii?Q?JwQcJMmDNRYMi+vQB+vC5AzG+fYpwNeKaD9WClTz2vGsLElQ4AFGAssWAWLl?= =?us-ascii?Q?eYI5p2Qp85a0GL7MtusgDfiQtAQeRRzbjxGFmKqFVcNEZ+Mjp1yZxTKK6KyE?= =?us-ascii?Q?ZECQb5ji1FzeyD2xZ+UvB7/OFJr3ighoeNuhF6sQ8dwR3TrPFz8Y0djbNqjA?= =?us-ascii?Q?UJbRs9ZyE8sBcp73clZGuIs8Xk+vH61inu5tKCsIwDNR3vBgm3JHVh0O6IWI?= =?us-ascii?Q?hj03lcHJ6hBV3IC2n8cIe1N5zo5GnCmkcO11FryyKK7WLheR90ifBWTYSKSB?= =?us-ascii?Q?kym4JfvRUEuaNsC7P+YRC3a0OFHv6EK2nybrhTW0Cxcve77ReHaGNzQqdZQ4?= =?us-ascii?Q?uRSDqM3bNt8gKae0gvn2eWMcVRArMorL+ti7smnVmW6WH1jeNR7hGiC11Cfy?= =?us-ascii?Q?W6oPUSPORpRfRsNgMPeTDWMy28qKzABqACICJoxPAFE0BY40nPBORggfCEMF?= =?us-ascii?Q?rnqcjQMwkQ=3D=3D?= X-OriginatorOrg: est.tech X-MS-Exchange-CrossTenant-Network-Message-Id: b32fe9a5-a072-40e6-4ec7-08deb0d937fe X-MS-Exchange-CrossTenant-AuthSource: BESP189MB3241.EURP189.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 May 2026 10:20:13.0721 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: d2585e63-66b9-44b6-a76e-4f4b217d97fd X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 8HNDnJJy+W3D77yKtw3sidsNjWPKCI2hwwCnji/QLwtWkgTdXtJA+HbkygY8GghKtoSVjf9SFlrFR+4lFKzVeQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PA1P189MB3601 On Wed, 13 May 2026, Adrian Hunter wrote: > On 12/05/2026 19:39, Frank Li wrote: >> On Tue, May 12, 2026 at 03:17:30PM +0300, Adrian Hunter wrote: >>> Master drivers may invoke i3c_master_do_daa_ext() during resume to >>> re-run Dynamic Address Assignment. As well as assigning addresses to >>> any newly arrived devices, this restores the dynamic address of devices >>> that lost it across system suspend, so it has to run as part of the >>> controller's resume path. >>> >>> A side effect of i3c_master_do_daa_ext() today is that it also >>> registers any newly discovered I3C devices with the driver model >>> inline, via i3c_master_register_new_i3c_devs(). Doing that from the >>> resume path is problematic: a hot-join-capable device may join the bus >>> during this same DAA, and registering it immediately would push driver >>> model work (probing, sysfs, etc.) into the controller's resume context, >>> where the rest of the system is not yet fully resumed and the >>> controller driver is still partway through its own resume sequence. >>> >>> Decouple discovery from registration: add a reg_work work item to >>> struct i3c_master_controller and have i3c_master_do_daa_ext() queue it >>> on master->wq (the freezable workqueue) instead of calling >>> i3c_master_register_new_i3c_devs() directly. The worker performs the >>> registration only when the controller is not shutting_down, and is >>> cancelled alongside hj_work in i3c_master_shutdown(). Because wq is >>> freezable, any newly observed devices end up being registered after >>> the system has finished resuming. >>> >>> i3c_master_register() also routes its initial post-bus-init registration >>> through reg_work, using flush_work() to keep probe-time behavior >>> synchronous. This keeps a single registration code path and ensures the >>> worker is the only writer of desc->dev. >> >> why not direct use hj_work? > > i3c_master_register_new_i3c_devs() use of desc->dev is racy, so > i3c_master_register_new_i3c_devs() must not be allowed to race > with itself. Having it only ever run via reg_work achieves that. This race was introduced in 3a379bbcea0a ("i3c: Add core I3C infrastructure") But since this path was exposed via sysfs in latest 7.1-rc via: 8ea0b60bc00d ("i3c: master: Add sysfs option to rescan bus via entdaa") I would argue that we should revert the sysfs addition from 7.1-rc until this fix is in place. > > -- > linux-i3c mailing list > linux-i3c@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-i3c >