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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?c8gNge2IyZDlJUjs73E9DnMSF3dyG4kZ/m3KQ+zd+EikmVmbpDm1N//Lf5Ln?= =?us-ascii?Q?JY1zXwghBv6pUBQKL3qMRolQ+QVzHOsF22egMG/rFqwWJuimr+yE1RoU9gEA?= =?us-ascii?Q?VxpaZr6n6JFts8m/fLWnhxHzd/TMywzXBxaIN6oP/yr7hCqhS5RJxsBb5EB2?= =?us-ascii?Q?w3Y9SrboGrgnLyWhF2zuMV6DkyE2jcjQehuZLy0lM6zQ29H2/HzaqikEygS2?= =?us-ascii?Q?W5MZ183D579YjOCOBSJycIVx5i+ImXWzP3yFDSjhvGmNUaDU0U2/5zYW/ybZ?= =?us-ascii?Q?6xH8GKtoVcQ42WAf+bBTwece7HkGN8iHtWXpWoiCA0/JO+hIMq2IhYGfuj7I?= =?us-ascii?Q?mVMDMYXmrXkoDtj5IgyRufEfglRkdCMiziwTOD2RsXtXjzO9SS8v7OYfwZkk?= =?us-ascii?Q?jm4H22SJSyAjt0Ttvkt5GaoeyXGhAwIbmd4YPqQGcpUhzavRB8i7Tg8BuUwc?= =?us-ascii?Q?mJBFXrHvP6ic1gC5MMDwAmofVvF/TXB2xnJUf45vxg5YmD06MCw+bjTOkvzJ?= =?us-ascii?Q?94UbY6Q4Q7ejg09QyskCAsOfAuq/Kk5SxWCVUbrG7slsms/8e3D1jDFyUwuc?= =?us-ascii?Q?BnQvEDSh71r27q+H+JOZx4tUoKF8TR9Wszy1QQs7ManzL1yBq80I44aEfR3A?= =?us-ascii?Q?x0OYVYFTF1RQh8kqsOFyEEEYgOFcJiYdHI414t8iBRb2jkk9L5+geERQwvVl?= =?us-ascii?Q?mCpYSkRR/3gK13RA11i5yyvS1ruhJCOBkRB2bLKiEVjqhnzaKiyVAL/eOUem?= =?us-ascii?Q?FYvp4AdGqn+Jp+s96aTUG0ldjWsqzdJjwYR2ebjmAJbQ4LQPA1eZ+NKJXsut?= =?us-ascii?Q?otH9/J7iqQQvOlH34DgYGlDV6FcIQ/b36ncGlUDipcbNnpbsC0Mz6PiWDu1M?= =?us-ascii?Q?VlttugYszW54mw96GJpjY6yn7tks4yO9ZchfeZHr5VYTXAqSROxBtbqBZOGu?= =?us-ascii?Q?zfnIBvVFOyH7pNQv31yTA0e59SnccpZRx4+JW+hNitAfY72uTOp1AjNkmRmm?= =?us-ascii?Q?p0pX7cWK9QWC+IpyTEcDQ6vkPIEZ95X6PhIlHrZY2nzAf0HENLp20GLhC99l?= =?us-ascii?Q?VdqRTfKktfnXJz/tPOrf9ezdnvz5oc+IBqRVDOnY+ZzeYDXIsrseIXe2CBRU?= =?us-ascii?Q?kSCQUpTw8ELocMszKtEzXPy707uDYWSzcX25dt/Uj7Dx3uBNg3wlU8LN8lyd?= =?us-ascii?Q?SURUgPVY5xQt53aEge6TIduwsPCN2u9c8cd8lN2F0JGJ6ppjXb9Siljv9v0p?= =?us-ascii?Q?qid/2+PSeBmRk9ezuB+1xPBJ6jKw/BjBD5Ki98hzPwM8lLXF7VAWrd3ijKRc?= =?us-ascii?Q?zj2z36882sfH6BEKrgbjrH7A?= X-OriginatorOrg: toradex.com X-MS-Exchange-CrossTenant-Network-Message-Id: 40941e55-ee68-47af-71b9-08d98efd4c81 X-MS-Exchange-CrossTenant-AuthSource: HE1PR0501MB2602.eurprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Oct 2021 10:28:01.2946 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: d9995866-0d9b-4251-8315-093f062abab4 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: HPhX5QsdLHTR8j2s2jPwJJngB+t6nVxmT0HS4g2aRkgpxDI8VQkjLe8fJE1fzjLugA167GnexVSELLJOv7s08CvPyjHOtlsM8WxSDh5cARk= X-MS-Exchange-Transport-CrossTenantHeadersStamped: HE1PR05MB3243 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 14, 2021 at 10:01:53AM +0200, Francesco Dolcini wrote: > Hello Greg, > > On Thu, Oct 14, 2021 at 09:33:55AM +0200, Greg Kroah-Hartman wrote: > > On Thu, Oct 14, 2021 at 09:10:52AM +0200, Francesco Dolcini wrote: > > > From: Stefan Agner > > > > > > If the device used as a serial console gets un/re-binded, then > > > register_console() will call imx_uart_setup_console() again. > > > Drop __init so that imx_uart_setup_console() can be safely called > > > at runtime. > > > > > > Signed-off-by: Stefan Agner > > > Signed-off-by: Francesco Dolcini > > > --- > > > drivers/tty/serial/imx.c | 4 ++-- > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > What commit does this "fix"? > > root@colibri-imx6ull-06746657:~# cat /sys/devices/virtual/tty/console/active > tty1 ttymxc0 > root@colibri-imx6ull-06746657:~# echo -n N > /sys/devices/virtual/tty/console/subsystem/ttymxc0/console > root@colibri-imx6ull-06746657:~# echo -n Y > /sys/devices/virtual/tty/console/subsystem/ttymxc0/console > > struct console ->setup is called at that time, but imx_uart_console_setup() is gone ... This specific way I described here to reproduce the issue was introduced with a3cb39d258ef serial: core: Allow detach and attach serial device for console that is kernel 5.9+ (Andy added to to:) But the original report was about bind/unbind of the uart driver, I guess this is possible since way more time. > > According to the original report from Stefan the issue is the same with unbind/bind of the console, > see https://marc.info/?l=linux-serial&m=154221779312036&w=2. > > > > Should this go to stable kernels? If so, how far back? > This is present also in 4.19 kernel, I feel like the issue is there since it is possible to unbind > a console driver (since ever considering the current LTS releases?). I could > investigate this a little bit more. > > We have this patch in our kernel branch since 3 years but for some reason we never managed to upstream it. > > > Francesco