Commit d2dc13b5 authored Jan 06, 2014 by Wang Dongsheng Committed by Scott Wood Jan 09, 2014

powerpc/mpic_timer: fix convert ticks to time subtraction overflow



In some cases tmp_sec may be greater than ticks, because in the process
of calculation ticks and tmp_sec will be rounded.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

parent 0fd79588

arch/powerpc/sysdev/mpic_timer.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -97,6 +97,9 @@ static void convert_ticks_to_time(struct timer_group_priv *priv,
		time->tv_sec = (__kernel_time_t)div_u64(ticks, priv->timerfreq);
		tmp_sec = (u64)time->tv_sec * (u64)priv->timerfreq;

		time->tv_usec = 0;

		if (tmp_sec <= ticks)
		time->tv_usec = (__kernel_suseconds_t)
		div_u64((ticks - tmp_sec) * 1000000, priv->timerfreq);