[PATCH] hrtimer: fix an explicit cast in __ktime_divns()

From: Wen Yang
Date: Thu Jan 30 2020 - 08:09:04 EST


do_div() does a 64-by-32 division, while the divisor 'div' is
explicitly casted to unsigned long, thus 64-bit on 64-bit platforms.
In addition, the above lines also ensures that the divisor is less
than 2^32. Hence the proper cast type is u32.

Signed-off-by: Wen Yang <wenyang@xxxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
kernel/time/hrtimer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index d8b62f93fc8d..57e543860660 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -311,7 +311,7 @@ s64 __ktime_divns(const ktime_t kt, s64 div)
div >>= 1;
}
tmp >>= sft;
- do_div(tmp, (unsigned long) div);
+ do_div(tmp, (u32) div);
return dclc < 0 ? -tmp : tmp;
}
EXPORT_SYMBOL_GPL(__ktime_divns);
--
2.23.0