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From: Tal Gilboa <talgi@mellanox.com>
Date: Thu, 29 Mar 2018 13:53:52 +0300
Subject: net/dim: Fix int overflow
Patch-mainline: v4.16
Git-commit: f97c3dc3c0e8d23a5c4357d182afeef4c67f5c33
References: bsc#1103990 FATE#326006

When calculating difference between samples, the values
are multiplied by 100. Large values may cause int overflow
when multiplied (usually on first iteration).
Fixed by forcing 100 to be of type unsigned long.

Fixes: 4c4dbb4a7363 ("net/mlx5e: Move dynamic interrupt coalescing code to include/linux")
Signed-off-by: Tal Gilboa <talgi@mellanox.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 include/linux/net_dim.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/net_dim.h
+++ b/include/linux/net_dim.h
@@ -231,7 +231,7 @@ static inline void net_dim_exit_parking(
 }
 
 #define IS_SIGNIFICANT_DIFF(val, ref) \
-	(((100 * abs((val) - (ref))) / (ref)) > 10) /* more than 10% difference */
+	(((100UL * abs((val) - (ref))) / (ref)) > 10) /* more than 10% difference */
 
 static inline int net_dim_stats_compare(struct net_dim_stats *curr,
 					struct net_dim_stats *prev)