The sysrq code is taking a spinlock from both interrupt and process context
in an unsafe and deadlocky manner.

Move all those inlined functions out of sysrq.h, into sysrq.c then withdraw
all those exported-to-modules helper functions then remove
__sysrq_trylock_table() altogether and then use spin_lock_irqsave() in the
appropriate places.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>