Patch "mlxsw: spectrum_router: Correctly dump neighbour activity" has been added to the 4.8-stable tree

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

mlxsw: spectrum_router: Correctly dump neighbour activity

to the 4.8-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:
mlxsw-spectrum_router-correctly-dump-neighbour-activity.patch
and it can be found in the queue-4.8 subdirectory.

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

From: Arkadi Sharshevsky <[email protected]>
Date: Fri, 11 Nov 2016 16:34:26 +0100
Subject: mlxsw: spectrum_router: Correctly dump neighbour activity

From: Arkadi Sharshevsky <[email protected]>

[ Upstream commit 42cdb338f40a98e6558bae35456fe86b6e90e1ef ]

The device's neighbour table is periodically dumped in order to update the kernel about active neighbours. A single dump session may span multiple queries, until the response carries less records than requested or when a record (can contain up to four neighbour entries) is not full. Current code stops the session when the number of returned records is zero, which can result in infinite loop in case of high packet rate.

Fix this by stopping the session according to the above logic.

---
 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c |   22 +++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

@@ -777,6 +777,26 @@ static void mlxsw_sp_router_neigh_rec_pr
 	}
 }
 
+static bool mlxsw_sp_router_rauhtd_is_full(char *rauhtd_pl)
+{
+	u8 num_rec, last_rec_index, num_entries;
+
+	num_rec = mlxsw_reg_rauhtd_num_rec_get(rauhtd_pl);
+	last_rec_index = num_rec - 1;
+
+	if (num_rec < MLXSW_REG_RAUHTD_REC_MAX_NUM)
+		return false;
+	if (mlxsw_reg_rauhtd_rec_type_get(rauhtd_pl, last_rec_index) ==
+	    MLXSW_REG_RAUHTD_TYPE_IPV6)
+		return true;
+
+	num_entries = mlxsw_reg_rauhtd_ipv4_rec_num_entries_get(rauhtd_pl,
+								last_rec_index);
+	if (++num_entries == MLXSW_REG_RAUHTD_IPV4_ENT_PER_REC)
+		return true;
+	return false;
+}
+
 static int mlxsw_sp_router_neighs_update_rauhtd(struct mlxsw_sp *mlxsw_sp)
 {
 	char *rauhtd_pl;

@@ -803,7 +823,7 @@ static int mlxsw_sp_router_neighs_update
 		for (i = 0; i < num_rec; i++)
 			mlxsw_sp_router_neigh_rec_process(mlxsw_sp, rauhtd_pl,
 							  i);
-	} while (num_rec);
+	} while (mlxsw_sp_router_rauhtd_is_full(rauhtd_pl));
 	rtnl_unlock();
 
 	kfree(rauhtd_pl);

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

queue-4.8/mlxsw-spectrum_router-correctly-dump-neighbour-activity.patch