Rather than blindly re-enabling interrupts in die(), save their state
upon entry and then restore that state.

If the kernel is in really bad condition and faults with interrupts disabled,
re-enabling them in die() may cause even more trouble, implying more chances
of data corruption.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>