[RFC][PATCH 2/5] time: Fix abs() usage with 64-bit values.

From: John Stultz
Date: Mon Sep 14 2015 - 21:06:01 EST


This patch fixes a usage of abs() with a 64-bit value which could
truncate the result to 32-bits, by replacing it with abs64().

In this case, its unlikely any issue could have been caused by
this, since we're calculating a second delta, which wouldn't be
larger then 32-bit.

Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Cc: Richard Cochran <richardcochran@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
kernel/time/timekeeping.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 3739ac6..3172823f 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1464,7 +1464,7 @@ int timekeeping_suspend(void)
*/
delta = timespec64_sub(tk_xtime(tk), timekeeping_suspend_time);
delta_delta = timespec64_sub(delta, old_delta);
- if (abs(delta_delta.tv_sec) >= 2) {
+ if (abs64(delta_delta.tv_sec) >= 2) {
/*
* if delta_delta is too large, assume time correction
* has occurred and set old_delta to the current delta.
--
1.9.1

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