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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?NoPPUwQescBsmErYGGxaZ1wTfGylAnPRAWwnT2LfH0tHifXDLHbhlIl2BgIF?= =?us-ascii?Q?/QwnFfRRHn9wL2AM5ANHA/9erTvGFpZ8RC64A+RsDf/XYHLbVkObwtgirBxw?= =?us-ascii?Q?o15J2JDlgtkFbIQGTV1Ac4h61g6o8KvjvU26Qt5wCs8iUupmUnhNYke27GVD?= =?us-ascii?Q?mDVqzSGNDlCblc1jCA4s/PpkLGGjJb/KGTrgHmWO7W71ONzrrFC13JafC4S5?= =?us-ascii?Q?d1GEqCTzSTLf8GITDdMZBrCit7KciEpXgnSwIksECu/D53NxuXHqeueyveJf?= =?us-ascii?Q?BNyMy/r+J67IGG1r9GsYkIcNNcH0bNxU9EW3IrVQZimM5Gjq23hqpG+od93d?= =?us-ascii?Q?HsVtN8dyfhrPHlFMp0Yq5ZGnsQIk+p1gwJVqFS6171pXuWCvHqPltF7LxEB2?= =?us-ascii?Q?vtTkDms/IG0A9wiX9uGEu2i5Hw16Qqm/M2MfYAwftTQ+j+XrNTZsRSklKaiR?= =?us-ascii?Q?rZBLL275AyyrK/W2SiwZlTHAeljTbjri2WHun0Hp4h8FlBGDgdwQwl4+PGRx?= =?us-ascii?Q?yz+9TZUDg4GtmEGcptNZHeYiAdXPhzdOG9GyKGpU1+Ymdkvj8oRqLMFxC2t6?= =?us-ascii?Q?tBbWc6lMDU10pwWnntNuRTxOaBlhEQxFJUjulVbTgW7fZIwH1X3cCGWp+cu4?= =?us-ascii?Q?/gf5RSU8JiKzqWqphkIhyzK4wpzz913LLvR2elrS895/XTTtW0+jd5CDG2+J?= =?us-ascii?Q?qM09TQOp5l+wjLdked3YAj2TbE/O7Qoy0ySuMf6PTzvov3DhBjiV3nBGurNF?= =?us-ascii?Q?Z8W7xdYzbwY1YvdeeTBV3swDLRhTFaMNaR256fWTiiwVicf+X57QqIooHay/?= =?us-ascii?Q?DufNgG4UBL9v6rEJ7QZYMMKNzrfouKPNMAgS36jOxFz1+jHpDSUIhoa1ZJ2R?= =?us-ascii?Q?tWhFMNBOR5q1Wp6u2NghuPSx/CXVC9I46LallQenhWczDO+Qu+2Is0VQqeP0?= =?us-ascii?Q?45abYcwIWjzhL3/yxVz25mQKWPZuj6HPG5sOudrQuMCL4puj80wX+KFGouWv?= =?us-ascii?Q?rheBqYeQnGzme8esrwzokkxAbvfpR246Q5hl8I41VPVnTVW1ICntJ9ibGCfx?= =?us-ascii?Q?IEp3gjC7ilZG+dE+ADI8qZeBNl1D4PBTfZVfuWcIdW5B0QkE2mWUmo42K7Oq?= =?us-ascii?Q?sycDYRcpGeJbAme3+7UnodHekgnlr7hLg8CMvAElTxyKMbAdWAdw3WvLNDP2?= =?us-ascii?Q?QGRIpdJJXHb6JMlhQi6hjTRcjyuxxIsE+pZGs7Sx+htSOOd5SDXAoKBWjhXr?= =?us-ascii?Q?fc4zNTpXE+ZKsGmyISMr/cJena4ipuX5+yCrFpis68oUKiF60ve/oxf++j6b?= =?us-ascii?Q?IB0JuslDvEWL5mJo1ArvxLxU?= X-OriginatorOrg: toradex.com X-MS-Exchange-CrossTenant-Network-Message-Id: bbbdbd71-0e3a-4e4a-ea15-08d98ee8e37b X-MS-Exchange-CrossTenant-AuthSource: HE1PR0501MB2602.eurprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Oct 2021 08:01:55.0991 (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: zzZVxX9Sxe2Bx2+EfxIeDMJs2Cmtb7QkVgim8DFwymUD7twUZ04xa+FgTAyrGIyE6Ny0KxlM9gJQkD6iIq+LbHWXWUnu4zpLhTyMPD/m5Ls= X-MS-Exchange-Transport-CrossTenantHeadersStamped: HE1PR0501MB2345 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 ... 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