Patch "net: fix harmonize_features() vs NETIF_F_HIGHDMA" has been added to the 4.9-stable tree

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

net: fix harmonize_features() vs NETIF_F_HIGHDMA

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:
net-fix-harmonize_features-vs-netif_f_highdma.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 <[email protected]> know about it.

From: Eric Dumazet <[email protected]>
Date: Wed, 18 Jan 2017 12:12:17 -0800
Subject: net: fix harmonize_features() vs NETIF_F_HIGHDMA

From: Eric Dumazet <[email protected]>

[ Upstream commit 7be2c82cfd5d28d7adb66821a992604eb6dd112e ]

Ashizuka reported a highmem oddity and sent a patch for freescale fec driver.

But the problem root cause is that core networking stack must ensure no skb with highmem fragment is ever sent through a device that does not assert NETIF_F_HIGHDMA in its features.

We need to call illegal_highdma() from harmonize_features() regardless of CSUM checks.

---
 net/core/dev.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

@@ -2815,9 +2815,9 @@ static netdev_features_t harmonize_featu
 	if (skb->ip_summed != CHECKSUM_NONE &&
 	    !can_checksum_protocol(features, type)) {
 		features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
-	} else if (illegal_highdma(skb->dev, skb)) {
-		features &= ~NETIF_F_SG;
 	}
+	if (illegal_highdma(skb->dev, skb))
+		features &= ~NETIF_F_SG;
 
 	return features;
 }

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