[PATCH] hpet rtc emulation: add watchdog timer

[PATCH] hpet rtc emulation: add watchdog timer

To prevent the emulated RTC timer from stopping when interrupts are delayed
for too long, disable interrupts around all of the register initialization,
and check that the interrupt handler did not schedule the next interrupt in
the past.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Vojtech Pavlik <vojtech@suse.cz>
Cc: Robert Picco <Robert.Picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>