'f' - Will call oom_kill to kill a memory hog process.
-'g' - Used by kgdb on ppc and sh platforms.
+'g' - Used by kgdb (kernel debugger)
'h' - Will display help (actually any other key than those listed
here will display help. but 'h' is easy to remember :-)
'u' - Will attempt to remount all mounted filesystems read-only.
-'v' - Dumps Voyager SMP processor info to your console.
+'v' - Forcefully restores framebuffer console
+'v' - Causes ETM buffer dump [ARM-specific]
'w' - Dumps tasks that are in uninterruptable (blocked) state.
'x' - Used by xmon interface on ppc/powerpc platforms.
+'y' - Show global CPU Registers [SPARC-64 specific]
+
'z' - Dump the ftrace buffer
'0'-'9' - Sets the console log level, controlling which kernel messages
* I hit SysRq, but nothing seems to happen, what's wrong?
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-There are some keyboards that send different scancodes for SysRq than the
-pre-defined 0x54. So if SysRq doesn't work out of the box for a certain
-keyboard, run 'showkey -s' to find out the proper scancode sequence. Then
-use 'setkeycodes <sequence> 84' to define this sequence to the usual SysRq
-code (84 is decimal for 0x54). It's probably best to put this command in a
-boot script. Oh, and by the way, you exit 'showkey' by not typing anything
-for ten seconds.
+There are some keyboards that produce a different keycode for SysRq than the
+pre-defined value of 99 (see KEY_SYSRQ in include/linux/input.h), or which
+don't have a SysRq key at all. In these cases, run 'showkey -s' to find an
+appropriate scancode sequence, and use 'setkeycodes <sequence> 99' to map
+this sequence to the usual SysRq code (e.g., 'setkeycodes e05b 99'). It's
+probably best to put this command in a boot script. Oh, and by the way, you
+exit 'showkey' by not typing anything for ten seconds.
* I want to add SysRQ key events to a module, how does it work?
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