LTS "sysrq: Restore original console_loglevel when sysrq disabled"

From: Rantala, Tommi T. (Nokia - FI/Espoo)
Date: Mon Mar 02 2020 - 02:43:09 EST


Hi Greg, Sasha,

Can you cherry-pick these two sysrq patches to LTS kernels?
They're introduced in v5.1-rc1 and should go to all prior LTS versions.


commit 075e1a0c50f59ea210561d0d0fedbd945615df78
Author: Petr Mladek <pmladek@xxxxxxxx>
Date: Fri Jan 11 13:45:15 2019 +0100

sysrq: Restore original console_loglevel when sysrq disabled

The sysrq header line is printed with an increased loglevel
to provide users some positive feedback.

The original loglevel is not restored when the sysrq operation
is disabled. This bug was introduced in 2.6.12 (pre-git-history)
by the commit ("Allow admin to enable only some of the Magic-Sysrq
functions").


commit c3fee60908db4a8594f2e4a2131998384b8fa006
Author: Petr Mladek <pmladek@xxxxxxxx>
Date: Fri Jan 11 17:20:37 2019 +0100

sysrq: Remove duplicated sysrq message

The commit 97f5f0cd8cd0a0544 ("Input: implement SysRq as a separate
input
handler") added pr_fmt() definition. It caused a duplicated message
prefix in the sysrq header messages, for example:

[ 177.053931] sysrq: SysRq : Show backtrace of all active CPUs
[ 742.864776] sysrq: SysRq : HELP : loglevel(0-9) reboot(b) crash(c)

Fixes: 97f5f0cd8cd0a05 ("Input: implement SysRq as a separate input
handler")