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Questions tagged [magic-sysrq]

The "magic sysrq" key sequence is a feature of the Linux kernel that, when enabled, provides debugging and disaster recovery features on the system console and serial console.

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How to read the output of the show-memory-usage SysRq?

I couldn’t find any (recent) documentation on reading the output of the show-memory-usage SysRq (Alt+SysRq+m). So what can one learn from looking at it? Here is an example output form my box (Kernel ...
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Can't figure out the way to trigger Magic Sys Keys via keyboard debian 9 lxdm 0.53-2 xfce4.12.3

I use a debian 9 with Magic Sys Keys enabled : sysctl -a | grep sysrq kernel.sysrq = 1 if I trigger in CLI, it works : echo f > /proc/sysrq-trigger I have something like : emergency sync ...
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Kernel Crash/ Cpu error?

First I will describe my system and then my problem: I have an Assus F555L laptop with an i3 and Intel Integrated Graphics. It is running Linux Mint 17.3 and Windows 10 dual booted. I do not have ...
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Undo Magic SysRq “remount-ro”

Is there a way to undo an accidental Magic SysRq "remount-ro"? On my notebook keyboard, this combination happens all too often... I tried to remount the roor partition with mount -o remount,rw /dev/...
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reisub, get detailed processes usage

I'm using the magic SysRq keys when my computer is frozen. The downside is that with REISUB, there is no detailed feedback of the computer state: I would like to find which processes are causing the ...
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Under what circumstance could switching tty's and entering commands freeze?

I noticed, that when booted from a live disc, and the RAM is filled up nearly, the live DVD starts being accessed far more often (probably due to exhausted and squished block cache) and switching tty'...
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176 views

How to stop a SysRq command?

I used SysRq+J (thaw), now I am being flooded with printk messages: emergency thaw on sr0. It will never stop. I do not wish to wait, until a SysRq command ends while blocking the terminal all the ...
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316 views

Cannot get kernel crash dump saved and reboot

I need to get a crash dump of my linux kernel. I am going to describe the scenario: Hardware: Notebook Dell E5450. Linux Distribution: Linux Mint 18.3 (Ubuntu 16.04). SysRq: enabled by /etc/sysctl.d/...