This is a note to let you know that I've just added the patch titled
net: lantiq: Add locking for TX DMA channel
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-lantiq-add-locking-for-tx-dma-channel.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 f9317ae5523f99999fb54c513ebabbb2bc887ddf Mon Sep 17 00:00:00 2001
From: Hauke Mehrtens <hauke@xxxxxxxxxx>
Date: Tue, 22 Sep 2020 23:41:12 +0200
Subject: net: lantiq: Add locking for TX DMA channel
From: Hauke Mehrtens <hauke@xxxxxxxxxx>
commit f9317ae5523f99999fb54c513ebabbb2bc887ddf upstream.
The TX DMA channel data is accessed by the xrx200_start_xmit() and the
xrx200_tx_housekeeping() function from different threads. Make sure the
accesses are synchronized by acquiring the netif_tx_lock() in the
xrx200_tx_housekeeping() function too. This lock is acquired by the
kernel before calling xrx200_start_xmit().
Signed-off-by: Hauke Mehrtens <hauke@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/lantiq_xrx200.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/net/ethernet/lantiq_xrx200.c
+++ b/drivers/net/ethernet/lantiq_xrx200.c
@@ -245,6 +245,7 @@ static int xrx200_tx_housekeeping(struct
int pkts = 0;
int bytes = 0;
+ netif_tx_lock(net_dev);
while (pkts < budget) {
struct ltq_dma_desc *desc = &ch->dma.desc_base[ch->tx_free];
@@ -268,6 +269,7 @@ static int xrx200_tx_housekeeping(struct
net_dev->stats.tx_bytes += bytes;
netdev_completed_queue(ch->priv->net_dev, pkts, bytes);
+ netif_tx_unlock(net_dev);
if (netif_queue_stopped(net_dev))
netif_wake_queue(net_dev);
Patches currently in stable-queue which might be from hauke@xxxxxxxxxx are
queue-5.4/net-lantiq-add-locking-for-tx-dma-channel.patch
