linux-kernel - Issue in Kernel docs / Admin Guide / SysRq

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Message-ID: <7ca05672-dc20-413f-a923-f77ce0a9d307@anselmschueler.com>
Date: Fri, 3 Oct 2025 14:32:57 +0200
From: Anselm Schüler <mail@...elmschueler.com>
To: linux-kernel@...r.kernel.org
Subject: Issue in Kernel docs / Admin Guide / SysRq

I’m writing here because I don’t know where to find Kernel docs 
(https://docs.kernel.org/) sources and submit patches.

The page “Linux Magic System Request Key Hacks” 
(https://docs.kernel.org/admin-guide/sysrq.html) says this:

“Write a single character to /proc/sysrq-trigger. Only the first 
character is processed, the rest of the string is ignored. However, it 
is not recommended to write any extra characters as the behavior is 
undefined and might change in the future versions. E.g.:
     echo t > /proc/sysrq-trigger”

I interpret the command as a suggestion of how to properly use 
/proc/sysrq-trigger, and not as an example of what not to do, and I 
believe many will share this interpretation. The command as listed will 
write TWO characters to /proc/sysrq-trigger.

Either the behaviour of ignoring \n should be codified and explicitly 
supported or this section should be changed.