[PATCH 5.10 08/21] net: stmmac: fix system hang if change mac address after interface ifdown

Greg Kroah-Hartman
2021-11-19T17:39:10Z

From: Joakim Zhang <qiangqing.zhang@nxp.com>

commit 4691ffb18ac908609aab07d13af7995b6b89d33c upstream.

Fix system hang with below sequences:
~# ifconfig ethx down
~# ifconfig ethx hw ether xx:xx:xx:xx:xx:xx

After ethx down, stmmac all clocks gated off and then register access causes
system hang.

Fixes: 5ec55823438e ("net: stmmac: add clocks management for gmac driver")
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Meng Li <Meng.Li@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -4324,12 +4324,21 @@ static int stmmac_set_mac_address(struct
struct stmmac_priv *priv = netdev_priv(ndev);
int ret = 0;

+ ret = pm_runtime_get_sync(priv->device);
+ if (ret < 0) {
+ pm_runtime_put_noidle(priv->device);
+ return ret;
+ }
+
ret = eth_mac_addr(ndev, addr);
if (ret)
- return ret;
+ goto set_mac_error;

stmmac_set_umac_addr(priv, priv->hw, ndev->dev_addr, 0);

+set_mac_error:
+ pm_runtime_put(priv->device);
+
return ret;
}