[PATCH AUTOSEL 5.12 38/39] net: ll_temac: Avoid ndo_start_xmit returning NETDEV_TX_BUSY
From: Sasha Levin <sashal@kernel.org>
Date: 2021-06-21 17:54:41
Also in:
linux-arm-kernel, lkml, netdev
Subsystem:
networking drivers, the rest, xilinx ll temac ethernet driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Esben Haabendal <redacted> [ Upstream commit f6396341194234e9b01cd7538bc2c6ac4501ab14 ] As documented in Documentation/networking/driver.rst, the ndo_start_xmit method must not return NETDEV_TX_BUSY under any normal circumstances, and as recommended, we simply stop the tx queue in advance, when there is a risk that the next xmit would cause a NETDEV_TX_BUSY return. Signed-off-by: Esben Haabendal <redacted> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/net/ethernet/xilinx/ll_temac_main.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c
index fb977bc4d838..b1caf56b2584 100644
--- a/drivers/net/ethernet/xilinx/ll_temac_main.c
+++ b/drivers/net/ethernet/xilinx/ll_temac_main.c@@ -938,6 +938,11 @@ temac_start_xmit(struct sk_buff *skb, struct net_device *ndev) wmb(); lp->dma_out(lp, TX_TAILDESC_PTR, tail_p); /* DMA start */ + if (temac_check_tx_bd_space(lp, MAX_SKB_FRAGS + 1)) { + netdev_info(ndev, "%s -> netif_stop_queue\n", __func__); + netif_stop_queue(ndev); + } + return NETDEV_TX_OK; }
--
2.30.2