From: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Date: Wed, 4 Nov 2020 13:45:14 +0000 (+0100)
Subject: net: eth-uclass: avoid running start() twice without stop()
X-Git-Url: http://git.dujemihanovic.xyz/%22http:/www.sics.se/static/%7B%7B%20%24.Site.BaseURL%20%7D%7Dposts/index.xml?a=commitdiff_plain;h=fa795f452541ce07b33be603de36cac3c5d7dfcf;p=u-boot.git

net: eth-uclass: avoid running start() twice without stop()

Running the start() handler twice without a stop() inbetween completely
breaks communication for some ethernet drivers like fec_mxc.

eth_halt() is called before each eth_init(). Due to the switch to
eth_is_active() in commit 68acb51f442f ("net: Only call halt on a driver
that has been init'ed"), this is not sufficient anymore when netconsole
is active: eth_init_state_only()/eth_halt_state_only() manipulate the
state check that is performed by eth_is_active() without actually
calling into the driver.

The issue can be triggered by starting a network operation (e.g. ping or
tftp) while netconsole is active.

Add an additional "running" flag that reflects the actual state of the
driver and use it to ensure that eth_halt() actually stops the device as
it is supposed to.

Fixes: 68acb51f442f ("net: Only call halt on a driver that has been init'ed")
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
---

diff --git a/net/eth-uclass.c b/net/eth-uclass.c
index 0156324032..7c2454f5ae 100644
--- a/net/eth-uclass.c
+++ b/net/eth-uclass.c
@@ -26,6 +26,7 @@ DECLARE_GLOBAL_DATA_PTR;
  */
 struct eth_device_priv {
 	enum eth_state_t state;
+	bool running;
 };
 
 /**
@@ -290,6 +291,7 @@ int eth_init(void)
 						dev_get_uclass_priv(current);
 
 					priv->state = ETH_STATE_ACTIVE;
+					priv->running = true;
 					return 0;
 				}
 			} else {
@@ -319,13 +321,16 @@ void eth_halt(void)
 	struct eth_device_priv *priv;
 
 	current = eth_get_dev();
-	if (!current || !eth_is_active(current))
+	if (!current)
 		return;
 
-	eth_get_ops(current)->stop(current);
 	priv = dev_get_uclass_priv(current);
-	if (priv)
-		priv->state = ETH_STATE_PASSIVE;
+	if (!priv || !priv->running)
+		return;
+
+	eth_get_ops(current)->stop(current);
+	priv->state = ETH_STATE_PASSIVE;
+	priv->running = false;
 }
 
 int eth_is_active(struct udevice *dev)
@@ -534,6 +539,7 @@ static int eth_post_probe(struct udevice *dev)
 #endif
 
 	priv->state = ETH_STATE_INIT;
+	priv->running = false;
 
 	/* Check if the device has a valid MAC address in device tree */
 	if (!eth_dev_get_mac_address(dev, pdata->enetaddr) ||