Patch "net/mlx5e: Fix fixpoint divide exception in mlx5e_am_stats_compare" has been added to the 4.14-stable tree

This is a note to let you know that I've just added the patch titled

net/mlx5e: Fix fixpoint divide exception in mlx5e_am_stats_compare

to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
net-mlx5e-fix-fixpoint-divide-exception-in-mlx5e_am_stats_compare.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Talat Batheesh <[email protected]>
Date: Sun, 21 Jan 2018 05:30:42 +0200
Subject: net/mlx5e: Fix fixpoint divide exception in mlx5e_am_stats_compare

From: Talat Batheesh <[email protected]>

[ Upstream commit e58edaa4863583b54409444f11b4f80dff0af1cd ]

Helmut reported a bug about division by zero while running traffic and doing physical cable pull test.

When the cable unplugged the ppms become zero, so when dividing the current ppms by the previous ppms in the next dim iteration there is division by zero.

This patch prevent this division for both ppms and epms.

---
 drivers/net/ethernet/mellanox/mlx5/core/en_rx_am.c |    6 ++++++
 1 file changed, 6 insertions(+)

@@ -197,9 +197,15 @@ static int mlx5e_am_stats_compare(struct
 		return (curr->bpms > prev->bpms) ? MLX5E_AM_STATS_BETTER :
 						   MLX5E_AM_STATS_WORSE;
 
+	if (!prev->ppms)
+		return curr->ppms ? MLX5E_AM_STATS_BETTER :
+				    MLX5E_AM_STATS_SAME;
+
 	if (IS_SIGNIFICANT_DIFF(curr->ppms, prev->ppms))
 		return (curr->ppms > prev->ppms) ? MLX5E_AM_STATS_BETTER :
 						   MLX5E_AM_STATS_WORSE;
+	if (!prev->epms)
+		return MLX5E_AM_STATS_SAME;
 
 	if (IS_SIGNIFICANT_DIFF(curr->epms, prev->epms))
 		return (curr->epms < prev->epms) ? MLX5E_AM_STATS_BETTER :

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/net-mlx5e-fix-fixpoint-divide-exception-in-mlx5e_am_stats_compare.patch