This is a note to let you know that I've just added the patch titled net: stmmac: reset Tx desc base address before restarting Tx 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-stmmac-reset-tx-desc-base-address-before-restarting-tx.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 f421031e3ff0dd288a6e1bbde9aa41a25bb814e6 Mon Sep 17 00:00:00 2001 From: Jongsung Kim <neidhard.kim@xxxxxxx> Date: Fri, 6 Dec 2019 20:40:00 +0900 Subject: net: stmmac: reset Tx desc base address before restarting Tx From: Jongsung Kim <neidhard.kim@xxxxxxx> commit f421031e3ff0dd288a6e1bbde9aa41a25bb814e6 upstream. Refer to the databook of DesignWare Cores Ethernet MAC Universal: 6.2.1.5 Register 4 (Transmit Descriptor List Address Register If this register is not changed when the ST bit is set to 0, then the DMA takes the descriptor address where it was stopped earlier. The stmmac_tx_err() does zero indices to Tx descriptors, but does not reset HW current Tx descriptor address. To fix inconsistency, the base address of the Tx descriptors should be rewritten before restarting Tx. Signed-off-by: Jongsung Kim <neidhard.kim@xxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Macpaul Lin <macpaul.lin@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -1987,6 +1987,8 @@ static void stmmac_tx_err(struct stmmac_ tx_q->cur_tx = 0; tx_q->mss = 0; netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, chan)); + stmmac_init_tx_chan(priv, priv->ioaddr, priv->plat->dma_cfg, + tx_q->dma_tx_phy, chan); stmmac_start_tx_dma(priv, chan); priv->dev->stats.tx_errors++; Patches currently in stable-queue which might be from neidhard.kim@xxxxxxx are queue-5.4/net-stmmac-reset-tx-desc-base-address-before-restarting-tx.patch