[Software] Magic SysRq keys disabled after reboot

[pizzafractal]

I can get the Magic SysRq keys to work by running the following as root in terminal:

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echo "1" > /proc/sys/kernel/sysrq

However, after reboot, the system reverts back to disabled:

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cat /proc/sys/kernel/sysrq
0

I have added this line ...

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kernel.sysrq = 1

... to "/etc/sysctl.conf", "/etc/sysctl.d/60-fix-sysrq.conf", "/etc/sysctl.d/51-alt-sysrq.conf" and "/etc/sysctl.d/99-sysctl.conf". This is a desktop computer for (nearly always) live music performance.

I have verified these kernel config. lines for the kernel in-use which is 6.0.0-7.1-liquorix-amd64:

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CONFIG_MAGIC_SYSRQ=y
CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE=0x1

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uname -a
Linux [username] 6.0.0-7.1-liquorix-amd64 #1 ZEN SMP PREEMPT_DYNAMIC liquorix 6.0-2.1~bullseye (2022-11-03 x86_64 GNU/Linux

What am I missing to get this working? Thank you!!

[canci]

You could also have a look at the Liquorix kernel changes. It's not a standard kernel after all.

[pizzafractal]

Thank you, it's working now. I don't know if this makes any sense but for what it's worth: The only thing I did differently after adding all those lines and rebooting a bunch of times back into the Liquorix kernel is boot into the standard 5.19.0-0.deb11.2-amd64 kernel where the keys were enabled as expected. Then, I rebooted back to the Liquorix kernel and the Magic SysRq keys are keeping enabled.

[canci]

Strange.

[sunrat]

Not strange at all. /proc/ is a virtual filesystem in which files are created dynamically by the kernel and don't persist across reboot. The only way for a user to persist MagicSysreq Keys is to make an entry in sysctl.conf or in a file in /etc/sysctl.d/ . Only one of those files is needed, certainly not four.

What is strange is that I use Liquorix (5.18 currently) and don't have anything in those files, but it seems to be default :

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cat /proc/sys/kernel/sysrq
1

Kernel config here shows:

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CONFIG_MAGIC_SYSRQ=y
CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE=0x1
CONFIG_MAGIC_SYSRQ_SERIAL=y
CONFIG_MAGIC_SYSRQ_SERIAL_SEQUENCE="m"

so I would have thought that sets it to "1" by default.

[pizzafractal]

One more "for what it's worth": I'm 100% on Debian repositories but it is a SpiralLinux configuration. Maybe there was something unexpected from that -- couldn't find any log entry about "sysrq" that seemed interesting. Thank you everyone!

[sunrat]

One more "for what it's worth": I'm 100% on Debian repositories but it is a SpiralLinux configuration. Maybe there was something unexpected from that -- couldn't find any log entry about "sysrq" that seemed interesting. Thank you everyone!

You should have mentioned that in your first post. This forum is for Debian. How are we to know what SpiralLinux configuration is? You should ask questions at SpiralLinux forums.
Moving topic to Offtopic.