Public bug reported: Description of the problem In Ubuntu 24.10 it was sufficient to edit /etc/sysctl.d/10-magic-sysrq.conf to override the default sysrq enablement mask at boot. In Ubuntu 25.04 doing this no longer works because any kernel.sysrq value set in that file is overridden by the value in /usr/lib/sysctl.d/50-default.conf . Here's the relevant snippet of 50-default.conf :
# System Request functionality of the kernel (SYNC) # # Use kernel.sysrq = 1 to allow all keys. # See https://docs.kernel.org/admin-guide/sysrq.html for a list # of values and keys. kernel.sysrq = 0x01b6 (when running "cat /proc/sys/kernel/sysrq" or "sysctl kernel.sysrq" the value will be reported as 438 which can make finding the file setting it more difficult) It would be useful if there was a comment in /etc/sysctl.d/10-magic- sysrq.conf hinting that the sysrq value is also set in /usr/lib/sysctl.d/50-default.conf or for /etc/sysctl.d/10-magic- sysrq.conf not to be made by default as it is misleading. ** Affects: procps (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to procps in Ubuntu. https://bugs.launchpad.net/bugs/2108979 Title: Please add a comment in 10-magic-sysrq.conf that it gets overriden by 50-default.conf Status in procps package in Ubuntu: New Bug description: Description of the problem In Ubuntu 24.10 it was sufficient to edit /etc/sysctl.d/10-magic-sysrq.conf to override the default sysrq enablement mask at boot. In Ubuntu 25.04 doing this no longer works because any kernel.sysrq value set in that file is overridden by the value in /usr/lib/sysctl.d/50-default.conf . Here's the relevant snippet of 50-default.conf : # System Request functionality of the kernel (SYNC) # # Use kernel.sysrq = 1 to allow all keys. # See https://docs.kernel.org/admin-guide/sysrq.html for a list # of values and keys. kernel.sysrq = 0x01b6 (when running "cat /proc/sys/kernel/sysrq" or "sysctl kernel.sysrq" the value will be reported as 438 which can make finding the file setting it more difficult) It would be useful if there was a comment in /etc/sysctl.d/10-magic- sysrq.conf hinting that the sysrq value is also set in /usr/lib/sysctl.d/50-default.conf or for /etc/sysctl.d/10-magic- sysrq.conf not to be made by default as it is misleading. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/procps/+bug/2108979/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp