It turns out gcc decides to allocate a stack frame in the current xmon setjmp
function.  This means the stack linkage we save away is destroyed when
returning from it and its just a matter of time before another function stomps
on it.

This should fix the problem Linas reported this week.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>