sysrq

When running a kernel with SysRq compiled in, this file controls the functions allowed to be invoked via the SysRq key. By default the file contains 1 which means that every possible SysRq request is allowed. Here is the list of all possible values:

  • 0 - disable sysrq completely
  • 1 - enable all functions of sysrq
  • >1 - bitmask of allowed sysrq functions (see below for detailed function description):
    • 2 - enable control of console logging level
    • 4 - enable control of keyboard (SAK, unraw)
    • 8 - enable debugging dumps of processes etc.
    • 16 - enable sync command
    • 32 - enable remount read-only
    • 64 - enable signalling of processes (term, kill, oom-kill)
    • 128 - allow reboot/poweroff
    • 256 - allow nicing of all RT tasks