linux-stable/drivers/tty
Sreenath Vijayan 1b743485e2 tty/sysrq: Replay kernel log messages on consoles via sysrq
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 <pmladek@suse.com>
Signed-off-by: Shimoyashiki Taichi <taichi.shimoyashiki@sony.com>
Reviewed-by: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Sreenath Vijayan <sreenath.vijayan@sony.com>
Link: https://lore.kernel.org/r/cc3b9b1aae60a236c6aed1dc7b0ffa2c7cd1f183.1710220326.git.sreenath.vijayan@sony.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-11 14:22:52 +02:00
..
hvc tty: hvc: Remove second semicolon 2024-04-09 15:49:00 +02:00
ipwireless tty: ipwireless: remove unused ipw_dev::attribute_memory 2023-11-23 19:16:03 +00:00
serdev serdev: make serdev_bus_type const 2024-02-06 14:35:38 +00:00
serial serial: max3100: Convert to_max3100_port() to be static inline 2024-04-11 14:08:40 +02:00
vt tty: vt: conmakehash: Don't mention the full path of the input in output 2024-04-09 15:50:12 +02:00
amiserial.c serial: ami: Mark driver struct with __refdata to prevent section mismatch 2024-04-09 15:50:22 +02:00
ehv_bytechan.c tty: ehv_bytechan: convert to u8 and size_t 2023-12-08 12:02:37 +01:00
goldfish.c tty: goldfish: Convert to platform remove callback returning void 2024-02-19 09:40:50 +01:00
Kconfig vt: remove superfluous CONFIG_HW_CONSOLE 2024-01-27 19:03:51 -08:00
Makefile tty: add rpmsg driver 2021-10-21 12:35:35 +02:00
mips_ejtag_fdc.c tty: mips_ejtag_fdc: Fix passing incompatible pointer type warning 2024-02-23 10:14:16 +01:00
moxa.c tty: moxa: convert to u8 and size_t 2023-12-08 12:02:38 +01:00
mxser.c tty: mxser: convert to u8 and size_t 2023-12-08 12:02:38 +01:00
n_gsm.c tty: n_gsm: replace deprecated strncpy with strscpy 2024-04-09 15:49:04 +02:00
n_hdlc.c tty: n_hdlc: convert to u8 and size_t 2023-12-08 12:02:38 +01:00
n_null.c tty: ldops: unify to u8 2023-08-11 21:12:47 +02:00
n_tty.c tty: invert return values of tty_{,un}throttle_safe() 2023-10-03 14:31:15 +02:00
nozomi.c tty: nozomi: convert to u8 and size_t 2023-12-08 12:02:38 +01:00
pty.c tty: make tty_operations::write()'s count size_t 2023-08-11 21:12:46 +02:00
rpmsg_tty.c tty: make tty_operations::write()'s count size_t 2023-08-11 21:12:46 +02:00
synclink_gt.c tty: make tty_operations::write()'s count size_t 2023-08-11 21:12:46 +02:00
sysrq.c tty/sysrq: Replay kernel log messages on consoles via sysrq 2024-04-11 14:22:52 +02:00
tty_audit.c tty: audit: unify to u8 2023-08-11 21:12:46 +02:00
tty_baudrate.c tty: Fix comment style in tty_termios_input_baud_rate() 2022-08-30 14:22:34 +02:00
tty_buffer.c tty: Don't include tty_buffer.h in tty.h 2024-02-18 18:59:59 +01:00
tty_io.c USB / Thunderbolt changes for 6.8-rc1 2024-01-18 11:43:55 -08:00
tty_ioctl.c tty: allow TIOCSLCKTRMIOS with CAP_CHECKPOINT_RESTORE 2023-12-15 14:20:03 +01:00
tty_jobctrl.c tty: tty_jobctrl: fix pid memleak in disassociate_ctty() 2023-09-18 11:14:43 +02:00
tty_ldisc.c tty: tty_ldisc: Remove the ret variable 2023-03-09 17:11:18 +01:00
tty_ldsem.c tty/ldsem: Fix syntax errors in comments 2021-12-21 09:15:49 +01:00
tty_mutex.c tty: remove TTY_MAGIC 2022-09-22 16:12:34 +02:00
tty_port.c tty: switch tty_port::xmit_* to u8 2023-12-08 12:02:37 +01:00
tty.h tty: convert THROTTLE constants into enum 2023-10-03 14:31:16 +02:00
ttynull.c tty: make tty_operations::write()'s count size_t 2023-08-11 21:12:46 +02:00
vcc.c tty: vcc: Add check for kstrdup() in vcc_probe() 2023-09-18 11:14:42 +02:00