Patch "net: dsa: Check return value of phy_connect_direct()" has been added to the 4.4-stable tree

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

net: dsa: Check return value of phy_connect_direct()

to the 4.4-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-dsa-check-return-value-of-phy_connect_direct.patch
and it can be found in the queue-4.4 subdirectory.

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

From: Florian Fainelli <[email protected]>
Date: Fri, 20 Jan 2017 16:05:05 -0800
Subject: net: dsa: Check return value of phy_connect_direct()

From: Florian Fainelli <[email protected]>

[ Upstream commit 4078b76cac68e50ccf1f76a74e7d3d5788aec3fe ]

We need to check the return value of phy_connect_direct() in dsa_slave_phy_connect() otherwise we may be continuing the initialization of a slave network device with a PHY that already attached somewhere else and which will soon be in error because the PHY device is in error.

The conditions for such an error to occur are that we have a port of our switch that is not disabled, and has the same port number as a PHY address (say both 5) that can be probed using the DSA slave MII bus. We end-up having this slave network device find a PHY at the same address as our port number, and we try to attach to it.

A slave network (e.g: port 0) has already attached to our PHY device, and we try to re-attach it with a different network device, but since we ignore the error we would end-up initializating incorrect device references by the time the slave network interface is opened.

The code has been (re)organized several times, making it hard to provide an exact Fixes tag, this is a bugfix nonetheless.

---
 net/dsa/slave.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

@@ -1006,10 +1006,8 @@ static int dsa_slave_phy_connect(struct
 	/* Use already configured phy mode */
 	if (p->phy_interface == PHY_INTERFACE_MODE_NA)
 		p->phy_interface = p->phy->interface;
-	phy_connect_direct(slave_dev, p->phy, dsa_slave_adjust_link,
-			   p->phy_interface);
-
-	return 0;
+	return phy_connect_direct(slave_dev, p->phy, dsa_slave_adjust_link,
+				  p->phy_interface);
 }
 
 static int dsa_slave_phy_setup(struct dsa_slave_priv *p,

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

queue-4.4/net-dsa-check-return-value-of-phy_connect_direct.patch queue-4.4/net-korina-fix-napi-versus-resources-freeing.patch queue-4.4/arm-dts-bcm5301x-correct-gic_ppi-interrupt-flags.patch queue-4.4/net-bgmac-start-transmit-queue-in-bgmac_open.patch queue-4.4/net-bgmac-fix-sof-bit-checking.patch queue-4.4/net-bgmac-remove-superflous-netif_carrier_on.patch