Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "One more fix from the timer departement:

    - Handle division of negative nanosecond values proper on 32bit.

      A recent cleanup wrecked the sign handling of the dividend and
      dropped the check for negative divisors"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ktime: Fix ktime_divns to do signed division

1 files changed, 8 insertions, 6 deletions

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 76d4bd962b19..93ef7190bdea 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -266,21 +266,23 @@ lock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags)
 /*
  * Divide a ktime value by a nanosecond value
  */
-u64 __ktime_divns(const ktime_t kt, s64 div)
+s64 __ktime_divns(const ktime_t kt, s64 div)
 {
-        u64 dclc;
         int sft = 0;
+        s64 dclc;
+        u64 tmp;
 
         dclc = ktime_to_ns(kt);
+        tmp = dclc < 0 ? -dclc : dclc;
+
         /* Make sure the divisor is less than 2^32: */
         while (div >> 32) {
                 sft++;
                 div >>= 1;
         }
-        dclc >>= sft;
-        do_div(dclc, (unsigned long) div);
-
-        return dclc;
+        tmp >>= sft;
+        do_div(tmp, (unsigned long) div);
+        return dclc < 0 ? -tmp : tmp;
 }
 EXPORT_SYMBOL_GPL(__ktime_divns);
 #endif /* BITS_PER_LONG >= 64 */