I have a Dell Latitude E6530. The keyboard has a SysRq key (Fn+Home). However the magic keys (especially the famous REISUB) doesn't work.
SysRq is enabled in /proc/sys/kernel/sysrq (I get 1 if I cat this file). It works from external USB keybord.
How can I have the Alt+SysRq+REISUB (in fact, Alt+Fn+Home+REISUB) reboot my system?