[PATCH] avr32: fixup kprobes preemption handling

While working on SH kprobes, I noticed that avr32 got the preemption
handling wrong in the no probe case.  The idea is that upon entry of
kprobe_handler() preemption is disabled outright across the life of the
kprobe, only to be re-enabled in post_kprobe_handler().

However, in the event that the probe is never activated, there's never any
chance of hitting the post probe handler, which allows for the current
avr32 implementation to disable preemption indefinitely, as it's currently
missing a re-enable when no probe is activated.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/avr32/kernel/kprobes.c

@@ -154,6 +154,7 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
 	return 1;
 
 no_kprobe:
+	preempt_enable_no_resched();
 	return ret;
 }