Patch "mlx4: do not call napi_schedule() without care" has been added to the 4.9-stable tree

Patch "mlx4: do not call napi_schedule() without care" has been added to the 4.9-stable tree

[gregkh]

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

    mlx4: do not call napi_schedule() without care

to the 4.9-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:
     mlx4-do-not-call-napi_schedule-without-care.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Wed Feb  1 08:50:24 CET 2017
From: Eric Dumazet <edumazet@google.com>
Date: Fri, 13 Jan 2017 08:39:24 -0800
Subject: mlx4: do not call napi_schedule() without care

From: Eric Dumazet <edumazet@google.com>


[ Upstream commit 8cf699ec849f4ca1413cea01289bd7d37dbcc626 ]

Disable BH around the call to napi_schedule() to avoid following warning

[   52.095499] NOHZ: local_softirq_pending 08
[   52.421291] NOHZ: local_softirq_pending 08
[   52.608313] NOHZ: local_softirq_pending 08

Fixes: 8d59de8f7bb3 ("net/mlx4_en: Process all completions in RX rings after port goes up")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Erez Shitrit <erezsh@mellanox.com>
Cc: Eugenia Emantayev <eugenia@mellanox.com>
Cc: Tariq Toukan <tariqt@mellanox.com>
Acked-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -1740,8 +1740,11 @@ int mlx4_en_start_port(struct net_device
 	/* Process all completions if exist to prevent
 	 * the queues freezing if they are full
 	 */
-	for (i = 0; i < priv->rx_ring_num; i++)
+	for (i = 0; i < priv->rx_ring_num; i++) {
+		local_bh_disable();
 		napi_schedule(&priv->rx_cq[i]->napi);
+		local_bh_enable();
+	}
 
 	netif_tx_start_all_queues(dev);
 	netif_device_attach(dev);


Patches currently in stable-queue which might be from edumazet@google.com are

queue-4.9/mlx4-do-not-call-napi_schedule-without-care.patch
queue-4.9/net-mlx5e-do-not-recycle-pages-from-emergency-reserve.patch
queue-4.9/net-fix-harmonize_features-vs-netif_f_highdma.patch
queue-4.9/tcp-fix-tcp_fastopen-unaligned-access-complaints-on-sparc.patch
queue-4.9/tcp-initialize-max-window-for-a-new-fastopen-socket.patch