timespec64_add_safe
cfg->start = timespec64_add_safe(cfg->start, curr_time);
*to = timespec64_add_safe(now, *to);
*to = timespec64_add_safe(*to, ts);
extern struct timespec64 timespec64_add_safe(const struct timespec64 lhs,
EXPORT_SYMBOL_GPL(timespec64_add_safe);