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charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed 2024-03-13 15:52:52, Sreenath Vijayan wrote: > When terminal is unresponsive, one cannot use dmesg to view > the printk ring buffer messages. Also, syslog services may be > disabled, especially on embedded systems, to check the messages > after a reboot. In this scenario, replay the messages in printk > ring buffer on consoles via sysrq by pressing sysrq+R. > > The console loglevel will determine which all kernel log messages > are displayed. The messages will be displayed only when > console_trylock() succeeds. Users could repeat the sysrq key when > it fails. If the owner of console subsystem lock is stuck, > repeating the key won't work. > > Suggested-by: Petr Mladek > Signed-off-by: Shimoyashiki Taichi > Reviewed-by: John Ogness > Signed-off-by: Sreenath Vijayan Reviewed-by: Petr Mladek Best Regards, Petr