[PATCH net 0/3] Few mvneta fixes

Hi David,

here is a patch set of few fixes. Without the first one, a kernel
configured with debug features ended to hang when the driver is built
as a module and is removed. This is quite is annoying for debugging!

The second patch fix a forgotten flag at the initial submission of the
driver.

The third patch is only really a cosmetic one so I have no problem to
not apply it for 4.5 and wait for 4.6.

I really would like to see the first one applied for 4.5 and for the
second I let you judge if it something needed for now or that should
wait the next release.

Thanks,

Gregory

Dmitri Epshtein (2):
  net: mvneta: enable change MAC address when interface is up
  net: mvneta: fix error messages in mvneta_port_down function

Gregory CLEMENT (1):
  net: mvneta: Fix spinlock usage

 drivers/net/ethernet/marvell/mvneta.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

-- 
2.5.0

From: Dmitri Epshtein <redacted>

This commit corrects error printing when shutting down the port. Also
magic numbers are replaced by existing macros.

Signed-off-by: Dmitri Epshtein <redacted>
Signed-off-by: Gregory CLEMENT <redacted>
---
 drivers/net/ethernet/marvell/mvneta.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 2ee05cebea75..225d933259c0 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c

@@ -873,14 +873,14 @@ static void mvneta_port_down(struct mvneta_port *pp)
 	do {
 		if (count++ >= MVNETA_RX_DISABLE_TIMEOUT_MSEC) {
 			netdev_warn(pp->dev,
-				    "TIMEOUT for RX stopped ! rx_queue_cmd: 0x08%x\n",
+				    "TIMEOUT for RX stopped ! rx_queue_cmd: 0x%08x\n",
 				    val);
 			break;
 		}
 		mdelay(1);
 
 		val = mvreg_read(pp, MVNETA_RXQ_CMD);
-	} while (val & 0xff);
+	} while (val & MVNETA_RXQ_ENABLE_MASK);
 
 	/* Stop Tx port activity. Check port Tx activity. Issue stop
 	 * command for active channels only

@@ -905,14 +905,14 @@ static void mvneta_port_down(struct mvneta_port *pp)
 		/* Check TX Command reg that all Txqs are stopped */
 		val = mvreg_read(pp, MVNETA_TXQ_CMD);
 
-	} while (val & 0xff);
+	} while (val & MVNETA_TXQ_ENABLE_MASK);
 
 	/* Double check to verify that TX FIFO is empty */
 	count = 0;
 	do {
 		if (count++ >= MVNETA_TX_FIFO_EMPTY_TIMEOUT) {
 			netdev_warn(pp->dev,
-				    "TX FIFO empty timeout status=0x08%x\n",
+				    "TX FIFO empty timeout status=0x%08x\n",
 				    val);
 			break;
 		}

-- 
2.5.0

In the previous patch, the spinlock was not initialized. While it didn't
cause any trouble yet it could be a problem to use it uninitialized.

The most annoying part was the critical section protected by the spinlock
in mvneta_stop(). Some of the functions could sleep as pointed when
activated CONFIG_DEBUG_ATOMIC_SLEEP. Actually, in mvneta_stop() we only
need to protect the is_stopped flagged, indeed the code of the notifier
for CPU online is protected by the same spinlock, so when we get the
lock, the notifer work is done.

Reported-by: Patrick Uiterwijk <redacted>
Signed-off-by: Gregory CLEMENT <redacted>
---
 drivers/net/ethernet/marvell/mvneta.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index b0ae69f84493..8dc7df2edff6 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c

@@ -3070,17 +3070,17 @@ static int mvneta_stop(struct net_device *dev)
 	struct mvneta_port *pp = netdev_priv(dev);
 
 	/* Inform that we are stopping so we don't want to setup the
-	 * driver for new CPUs in the notifiers
+	 * driver for new CPUs in the notifiers. The code of the
+	 * notifier for CPU online is protected by the same spinlock,
+	 * so when we get the lock, the notifer work is done.
 	 */
 	spin_lock(&pp->lock);
 	pp->is_stopped = true;
+	spin_unlock(&pp->lock);
+
 	mvneta_stop_dev(pp);
 	mvneta_mdio_remove(pp);
 	unregister_cpu_notifier(&pp->cpu_notifier);
-	/* Now that the notifier are unregistered, we can release le
-	 * lock
-	 */
-	spin_unlock(&pp->lock);
 	on_each_cpu(mvneta_percpu_disable, pp, true);
 	free_percpu_irq(dev->irq, pp->ports);
 	mvneta_cleanup_rxqs(pp);

@@ -3612,6 +3612,7 @@ static int mvneta_probe(struct platform_device *pdev)
 	dev->ethtool_ops = &mvneta_eth_tool_ops;
 
 	pp = netdev_priv(dev);
+	spin_lock_init(&pp->lock);
 	pp->phy_node = phy_node;
 	pp->phy_interface = phy_mode;
 

-- 
2.5.0

From: Dmitri Epshtein <redacted>

Function eth_prepare_mac_addr_change() is called as part of MAC
address change. This function check if interface is running.
To enable change MAC address when interface is running:
IFF_LIVE_ADDR_CHANGE flag must be set to dev->priv_flags field

Fixes: c5aff18204da ("net: mvneta: driver for Marvell Armada 370/XP
network unit")
Cc: stable at vger.kernel.org
Signed-off-by: Dmitri Epshtein <redacted>
Signed-off-by: Gregory CLEMENT <redacted>
---
 drivers/net/ethernet/marvell/mvneta.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 8dc7df2edff6..2ee05cebea75 100644
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c

@@ -3721,7 +3721,7 @@ static int mvneta_probe(struct platform_device *pdev)
 	dev->features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_TSO;
 	dev->hw_features |= dev->features;
 	dev->vlan_features |= dev->features;
-	dev->priv_flags |= IFF_UNICAST_FLT;
+	dev->priv_flags |= IFF_UNICAST_FLT | IFF_LIVE_ADDR_CHANGE;
 	dev->gso_max_segs = MVNETA_MAX_TSO_SEGS;
 
 	err = register_netdev(dev);

-- 
2.5.0

Dear Gregory,

On Tue, 8 Mar 2016 13:57:04 +0100 Gregory CLEMENT wrote:

This fix sleep in atomic issue. But
I see race here. Let's assume is_stopped is false.

cpu0:                           	cpu1:
mvneta_percpu_notifier():		mvneta_stop():

if (pp->is_stopped) {
	spin_unlock(&pp->lock);
	break;
}

					pp->is_stopped = true;
					spin_unlock(&pp->lock);


netif_tx_stop_all_queues(pp->dev);
for_each_online_cpu(other_cpu) {
....

Thanks,
Jisheng

From: Gregory CLEMENT <redacted>
Date: Tue,  8 Mar 2016 13:57:06 +0100

From: Dmitri Epshtein <redacted>

This commit corrects error printing when shutting down the port. Also
magic numbers are replaced by existing macros.

Signed-off-by: Dmitri Epshtein <redacted>
Signed-off-by: Gregory CLEMENT <redacted>

Individual patches should do one thing, rather than several at once.

Please split this up into two changes, thanks.