diff options
-rw-r--r-- | kernel/time/timekeeping_internal.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/time/timekeeping_internal.h b/kernel/time/timekeeping_internal.h index e20466ffc208..5be76270ec4a 100644 --- a/kernel/time/timekeeping_internal.h +++ b/kernel/time/timekeeping_internal.h @@ -17,7 +17,11 @@ static inline cycle_t clocksource_delta(cycle_t now, cycle_t last, cycle_t mask) { cycle_t ret = (now - last) & mask; - return (s64) ret > 0 ? ret : 0; + /* + * Prevent time going backwards by checking the MSB of mask in + * the result. If set, return 0. + */ + return ret & ~(mask >> 1) ? 0 : ret; } #else static inline cycle_t clocksource_delta(cycle_t now, cycle_t last, cycle_t mask) |