From 1baf2e50e48f10f0ea07d53e13381fd0da1546d2 Mon Sep 17 00:00:00 2001 From: Heyi Guo Date: Wed, 23 Feb 2022 11:14:36 +0800 Subject: drivers/net/ftgmac100: fix DHCP potential failure with systemd DHCP failures were observed with systemd 247.6. The issue could be reproduced by rebooting Aspeed 2600 and then running ifconfig ethX down/up. It is caused by below procedures in the driver: 1. ftgmac100_open() enables net interface and call phy_start() 2. When PHY is link up, it calls netif_carrier_on() and then adjust_link callback 3. ftgmac100_adjust_link() will schedule the reset task 4. ftgmac100_reset_task() will then reset the MAC in another schedule After step 2, systemd will be notified to send DHCP discover packet, while the packet might be corrupted by MAC reset operation in step 4. Call ftgmac100_reset() directly instead of scheduling task to fix the issue. Signed-off-by: Heyi Guo Signed-off-by: David S. Miller --- drivers/net/ethernet/faraday/ftgmac100.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'drivers/net/ethernet/faraday') diff --git a/drivers/net/ethernet/faraday/ftgmac100.c b/drivers/net/ethernet/faraday/ftgmac100.c index c1deb6e5d26c..d5356db7539a 100644 --- a/drivers/net/ethernet/faraday/ftgmac100.c +++ b/drivers/net/ethernet/faraday/ftgmac100.c @@ -1402,8 +1402,17 @@ static void ftgmac100_adjust_link(struct net_device *netdev) /* Disable all interrupts */ iowrite32(0, priv->base + FTGMAC100_OFFSET_IER); - /* Reset the adapter asynchronously */ - schedule_work(&priv->reset_task); + /* Release phy lock to allow ftgmac100_reset to aquire it, keeping lock + * order consistent to prevent dead lock. + */ + if (netdev->phydev) + mutex_unlock(&netdev->phydev->lock); + + ftgmac100_reset(priv); + + if (netdev->phydev) + mutex_lock(&netdev->phydev->lock); + } static int ftgmac100_mii_probe(struct net_device *netdev) -- cgit