From 67dfae0cd72fec5cd158b6e5fb1647b7dbe0834c Mon Sep 17 00:00:00 2001 From: John Stultz Date: Mon, 14 Sep 2015 18:05:20 -0700 Subject: [PATCH] clocksource: Fix abs() usage w/ 64bit values This patch fixes one cases where abs() was being used with 64-bit nanosecond values, where the result may be capped at 32-bits. This potentially could cause watchdog false negatives on 32-bit systems, so this patch addresses the issue by using abs64(). Signed-off-by: John Stultz Cc: Prarit Bhargava Cc: Richard Cochran Cc: Ingo Molnar Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1442279124-7309-2-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner --- kernel/time/clocksource.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 841b72f..3a38775 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -217,7 +217,7 @@ static void clocksource_watchdog(unsigned long data) continue; /* Check the deviation from the watchdog clocksource. */ - if ((abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD)) { + if (abs64(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) { pr_warn("timekeeping watchdog: Marking clocksource '%s' as unstable because the skew is too large:\n", cs->name); pr_warn(" '%s' wd_now: %llx wd_last: %llx mask: %llx\n", -- 2.7.4