tree a74aa7bacf920eb567cd7caa8027a06c96dbb220
parent 94df7de0289bc2df3d6e85cd2ece52bf42682f45
author Thomas Gleixner <tglx@linutronix.de> 1232879496 +0100
committer Ingo Molnar <mingo@elte.hu> 1233351334 +0100

hrtimer: prevent negative expiry value after clock_was_set()

Impact: prevent false positive WARN_ON() in clockevents_program_event()

clock_was_set() changes the base->offset of CLOCK_REALTIME and
enforces the reprogramming of the clockevent device to expire timers
which are based on CLOCK_REALTIME. If the clock change is large enough
then the subtraction of the timer expiry value and base->offset can
become negative which triggers the warning in
clockevents_program_event().

Check the subtraction result and set a negative value to 0.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>