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charset="us-ascii" Content-ID: <9701346C7DAC8A42B21AA3E54D542078@namprd04.prod.outlook.com> Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-OriginatorOrg: phil.gs X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BY5PR04MB6472.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: a4d9a3b6-05ae-475b-a08d-08df29495e49 X-MS-Exchange-CrossTenant-originalarrivaltime: 13 Oct 2026 16:45:20.0859 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 47d4f979-ea6f-4fcb-aea9-39371d64bc6b X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: tE+U12TJ+oR9efTRclmP6c0Ap9U8/c/FtnzkQLDCJ+UPLghCs5jSy/o76Ra0jodZ X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR04MB6480 On Sat, Oct 03, 2026 at 07:33:37PM +0300, Igor Putko wrote: > Fix this by acquiring port->mutex in serial_core_remove_one_port() after > console unregistration, clearing port->console under the mutex to prevent > data races with concurrent tty_port_shutdown(), and invoking > uart_shutdown(NULL, state) if the port remains initialized. I sent a patch for the same bug [1] without having seen this one. I ran my reproducers on tty-next 36844ea19656 plus this commit (810d467c11f0 in tty-testing), in a QEMU guest with KASAN. The 8250_pci case with INTx is fixed: the IRQ is freed on unbind, reading /proc/interrupts is clean and rebinding restores the console. It also fixes a second symptom, on a polled port (irq 0, UPF_IOREMAP), where serial8250_timeout() kept running after removal and dereferenced the cleared membase. A port held open across removal and a console that was never opened still work. Tested-by: Phil Rosenthal The patch uses scoped_guard(), which exists for mutexes from v6.5, so it won't build on the 6.1, 5.15 and 5.10 stable trees. If you don't plan to send backports for those, I can. [1] https://lore.kernel.org/r/20261013-serial-console-remove-v2-1-2eca1a92c= 10d@phil.gs Thanks, Phil