This is a note to let you know that I've just added the patch titled net: nxp: lpc_eth.c: avoid hang when bringing interface down to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-nxp-lpc_eth.c-avoid-hang-when-bringing-interface-down.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ace19b992436a257d9a793672e57abc28fe83e2e Mon Sep 17 00:00:00 2001 From: Trevor Woerner <twoerner@xxxxxxxxx> Date: Sun, 24 Oct 2021 13:50:02 -0400 Subject: net: nxp: lpc_eth.c: avoid hang when bringing interface down From: Trevor Woerner <twoerner@xxxxxxxxx> commit ace19b992436a257d9a793672e57abc28fe83e2e upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/nxp/lpc_eth.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/drivers/net/ethernet/nxp/lpc_eth.c +++ b/drivers/net/ethernet/nxp/lpc_eth.c @@ -1007,9 +1007,6 @@ static int lpc_eth_close(struct net_devi 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); @@ -1017,6 +1014,8 @@ static int lpc_eth_close(struct net_devi 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; Patches currently in stable-queue which might be from twoerner@xxxxxxxxx are queue-5.4/net-nxp-lpc_eth.c-avoid-hang-when-bringing-interface-down.patch