From 1623161f80a4b8bb284b0cc3118daf3ccd5bf923 Mon Sep 17 00:00:00 2001 From: Horatiu Vultur Date: Mon, 19 Feb 2024 09:00:43 +0100 Subject: [PATCH] net: sparx5: Add spinlock for frame transmission from CPU [ Upstream commit 603ead96582d85903baec2d55f021b8dac5c25d2 ] Both registers used when doing manual injection or fdma injection are shared between all the net devices of the switch. It was noticed that when having two process which each of them trying to inject frames on different ethernet ports, that the HW started to behave strange, by sending out more frames then expected. When doing fdma injection it is required to set the frame in the DCB and then make sure that the next pointer of the last DCB is invalid. But because there is no locks for this, then easily this pointer between the DCB can be broken and then it would create a loop of DCBs. And that means that the HW will continuously transmit these frames in a loop. Until the SW will break this loop. Therefore to fix this issue, add a spin lock for when accessing the registers for manual or fdma injection. Signed-off-by: Horatiu Vultur Reviewed-by: Daniel Machon Fixes: f3cad2611a77 ("net: sparx5: add hostmode with phylink support") Link: https://lore.kernel.org/r/20240219080043.1561014-1-horatiu.vultur@microchip.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/microchip/sparx5/sparx5_main.c | 1 + drivers/net/ethernet/microchip/sparx5/sparx5_main.h | 1 + drivers/net/ethernet/microchip/sparx5/sparx5_packet.c | 2 ++ 3 files changed, 4 insertions(+) diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_main.c b/drivers/net/ethernet/microchip/sparx5/sparx5_main.c index 3423c95cc84a..7031f41287e0 100644 --- a/drivers/net/ethernet/microchip/sparx5/sparx5_main.c +++ b/drivers/net/ethernet/microchip/sparx5/sparx5_main.c @@ -744,6 +744,7 @@ static int mchp_sparx5_probe(struct platform_device *pdev) platform_set_drvdata(pdev, sparx5); sparx5->pdev = pdev; sparx5->dev = &pdev->dev; + spin_lock_init(&sparx5->tx_lock); /* Do switch core reset if available */ reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch"); diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h index 7a83222caa73..cb3173d2b0e8 100644 --- a/drivers/net/ethernet/microchip/sparx5/sparx5_main.h +++ b/drivers/net/ethernet/microchip/sparx5/sparx5_main.h @@ -278,6 +278,7 @@ struct sparx5 { int xtr_irq; /* Frame DMA */ int fdma_irq; + spinlock_t tx_lock; /* lock for frame transmission */ struct sparx5_rx rx; struct sparx5_tx tx; /* PTP */ diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c b/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c index 6db6ac6a3bbc..ac7e1cffbcec 100644 --- a/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c +++ b/drivers/net/ethernet/microchip/sparx5/sparx5_packet.c @@ -244,10 +244,12 @@ netdev_tx_t sparx5_port_xmit_impl(struct sk_buff *skb, struct net_device *dev) } skb_tx_timestamp(skb); + spin_lock(&sparx5->tx_lock); if (sparx5->fdma_irq > 0) ret = sparx5_fdma_xmit(sparx5, ifh, skb); else ret = sparx5_inject(sparx5, ifh, skb, dev); + spin_unlock(&sparx5->tx_lock); if (ret == -EBUSY) goto busy;