Thread (5 messages) 5 messages, 2 authors, 2026-06-18
COLD42d

[PATCH net] net: airoha: Fix TX scheduler queue mask loop upper bound

From: Wayen Yan <hidden>
Date: 2026-06-17 03:31:06
Also in: linux-arm-kernel, linux-mediatek
Subsystem: airoha ethernet driver, networking drivers, the rest · Maintainers: Lorenzo Bianconi, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds

In airoha_qdma_set_chan_tx_sched(), the loop clearing queue mask was
using AIROHA_NUM_TX_RING (32) instead of AIROHA_NUM_QOS_QUEUES (8).

Each channel has 8 queues, and TXQ_DISABLE_CHAN_QUEUE_MASK(channel, i)
computes BIT(i + (channel * 8)). With i ranging 0..31, this causes:
- channel 0: clears bit 0..31 (all 4 channels) instead of 0..7
- channel 1: clears bit 8..31 (channels 1-3) instead of 8..15
- channel 2: clears bit 16..31 (channels 2-3) instead of 16..23
- channel 3: clears bit 24..31 (channel 3 only) - correct by accident

While BIT(32+) on arm64 produces 64-bit values truncated to 0 in u32
mask parameter, the loop still incorrectly clears queues within the
same channel beyond queue 7.

Fix by using AIROHA_NUM_QOS_QUEUES (8) as the loop upper bound.

Fixes: ef1ca9271313 ("net: airoha: Add sched HTB offload support")
Signed-off-by: Wayen Yan <redacted>
---
 drivers/net/ethernet/airoha/airoha_eth.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index 31cdb11cd7..a1eda13400 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c
@@ -2217,7 +2217,7 @@ static int airoha_qdma_set_chan_tx_sched(struct net_device *dev,
 	struct airoha_gdm_port *port = netdev_priv(dev);
 	int i;
 
-	for (i = 0; i < AIROHA_NUM_TX_RING; i++)
+	for (i = 0; i < AIROHA_NUM_QOS_QUEUES; i++)
 		airoha_qdma_clear(port->qdma, REG_QUEUE_CLOSE_CFG(channel),
 				  TXQ_DISABLE_CHAN_QUEUE_MASK(channel, i));
 
-- 
2.51.0

Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help