The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From ace19b992436a257d9a793672e57abc28fe83e2e Mon Sep 17 00:00:00 2001 From: Trevor Woerner <twoerner@xxxxxxxxx> Date: Sun, 24 Oct 2021 13:50:02 -0400 Subject: [PATCH] net: nxp: lpc_eth.c: avoid hang when bringing interface down A hard hang is observed whenever the ethernet interface is brought down. If the PHY is stopped before the LPC core block is reset, the SoC will hang. Comparing lpc_eth_close() and lpc_eth_open() I re-arranged the ordering of the functions calls in lpc_eth_close() to reset the hardware before stopping the PHY. Fixes: b7370112f519 ("lpc32xx: Added ethernet driver") Signed-off-by: Trevor Woerner <twoerner@xxxxxxxxx> Acked-by: Vladimir Zapolskiy <vz@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> diff --git a/drivers/net/ethernet/nxp/lpc_eth.c b/drivers/net/ethernet/nxp/lpc_eth.c index d29fe562b3de..c910fa2f40a4 100644 --- a/drivers/net/ethernet/nxp/lpc_eth.c +++ b/drivers/net/ethernet/nxp/lpc_eth.c @@ -1015,9 +1015,6 @@ static int lpc_eth_close(struct net_device *ndev) napi_disable(&pldat->napi); netif_stop_queue(ndev); - if (ndev->phydev) - phy_stop(ndev->phydev); - spin_lock_irqsave(&pldat->lock, flags); __lpc_eth_reset(pldat); netif_carrier_off(ndev); @@ -1025,6 +1022,8 @@ static int lpc_eth_close(struct net_device *ndev) writel(0, LPC_ENET_MAC2(pldat->net_base)); spin_unlock_irqrestore(&pldat->lock, flags); + if (ndev->phydev) + phy_stop(ndev->phydev); clk_disable_unprepare(pldat->clk); return 0;