4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Alexander Couzens <lynxis@xxxxxxx>
[ Upstream commit 5c968f48021a9b3faa61ac2543cfab32461c0e05 ]
mii_nway_restart is not pm aware which results in a rtnl deadlock.
Implement mii_nway_restart manual by setting BMCR_ANRESTART if
BMCR_ANENABLE is set.
To reproduce:
* plug an asix based usb network interface
* wait until the device enters PM (~5 sec)
* `ip link set eth1 up` will never return
Fixes: d9fe64e51114 ("net: asix: Add in_pm parameter")
Signed-off-by: Alexander Couzens <lynxis@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/usb/asix_devices.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -640,10 +640,12 @@ static void ax88772_restore_phy(struct u
priv->presvd_phy_advertise);
/* Restore BMCR */
+ if (priv->presvd_phy_bmcr & BMCR_ANENABLE)
+ priv->presvd_phy_bmcr |= BMCR_ANRESTART;
+
asix_mdio_write_nopm(dev->net, dev->mii.phy_id, MII_BMCR,
priv->presvd_phy_bmcr);
- mii_nway_restart(&dev->mii);
priv->presvd_phy_advertise = 0;
priv->presvd_phy_bmcr = 0;
}
