A Locking bug in the packet receive path was introduced with PR
#4973. The following patch prevents the driver from locking
after a few minutes with an endless flow of
[ 1434.185085] rtl838x-eth 1b00a300.ethernet eth0: Ring contention: r: 0, last
a28000f4, cur a28000f8
[ 1434.208971] rtl838x-eth 1b00a300.ethernet eth0: Ring contention: r: 0, last
a28000f4, cur a28000fc
[ 1434.794800] rtl838x-eth 1b00a300.ethernet eth0: Ring contention: r: 0, last
a28000f4, cur a28000fc
[ 1435.049187] rtl838x-eth 1b00a300.ethernet eth0: Ring contention: r: 0, last
a28000f4, cur a28000fc
Signed-off-by: Bjørn Mork <bj...@mork.no>
Signed-off-by: Birger Koblitz <m...@birger-koblitz.de>
---
.../realtek/files-5.10/drivers/net/ethernet/rtl838x_eth.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/target/linux/realtek/files-5.10/drivers/net/ethernet/rtl838x_eth.c
b/target/linux/realtek/files-5.10/drivers/net/ethernet/rtl838x_eth.c
index ab4a03550bd8..cf6aabc6142f 100644
--- a/target/linux/realtek/files-5.10/drivers/net/ethernet/rtl838x_eth.c
+++ b/target/linux/realtek/files-5.10/drivers/net/ethernet/rtl838x_eth.c
@@ -1254,8 +1254,9 @@ static int rtl838x_hw_receive(struct net_device *dev, int
r, int budget)
bool dsa = netdev_uses_dsa(dev);
struct dsa_tag tag;
- last = (u32 *)KSEG1ADDR(sw_r32(priv->r->dma_if_rx_cur + r * 4));
pr_debug("---------------------------------------------------------- RX
- %d\n", r);
+ spin_lock_irqsave(&priv->lock, flags);
+ last = (u32 *)KSEG1ADDR(sw_r32(priv->r->dma_if_rx_cur + r * 4));
do {
if ((ring->rx_r[r][ring->c_rx[r]] & 0x1)) {
@@ -1329,7 +1330,6 @@ static int rtl838x_hw_receive(struct net_device *dev, int
r, int budget)
}
/* Reset header structure */
- spin_lock_irqsave(&priv->lock, flags);
memset(h, 0, sizeof(struct p_hdr));
h->buf = data;
h->size = RING_BUFFER;
@@ -1338,12 +1338,13 @@ static int rtl838x_hw_receive(struct net_device *dev,
int r, int budget)
| (ring->c_rx[r] == (priv->rxringlen - 1) ? WRAP : 0x1);
ring->c_rx[r] = (ring->c_rx[r] + 1) % priv->rxringlen;
last = (u32 *)KSEG1ADDR(sw_r32(priv->r->dma_if_rx_cur + r * 4));
- spin_unlock_irqrestore(&priv->lock, flags);
} while (&ring->rx_r[r][ring->c_rx[r]] != last && work_done < budget);
// Update counters
priv->r->update_cntr(r, 0);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
return work_done;
}
--
2.30.2
_______________________________________________
openwrt-devel mailing list
openwrt-devel@lists.openwrt.org
https://lists.openwrt.org/mailman/listinfo/openwrt-devel
