Re: [PATCH net v2] net: airoha: fix ETS channel derivation in airoha_tc_setup_qdisc_ets()

Derive the hardware QoS channel from opt->parent instead of opt->handle
in airoha_tc_setup_qdisc_ets(). The ETS qdisc handle is either
user-specified or auto-allocated by qdisc_alloc_handle() and bears no
relation to the HTB leaf classid that identifies the hardware channel.
HTB derives the channel from TC_H_MIN(opt->classid), and ETS is always
attached as a child of an HTB leaf, so its opt->parent matches that
classid. Using opt->handle instead can cause two ETS qdiscs on different
HTB leaves to collide on the same hardware channel, corrupting scheduler
configuration and stats.

Fixes: 20bf7d07c956 ("net: airoha: Add sched ETS offload support")
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
Changes in v2:
- Rebase on top of net main branch
- Link to v1: https://lore.kernel.org/r/20260704-airoha-ets-handle-fix-v1-1-42516b3549a1@kernel.org (local)
---
 drivers/net/ethernet/airoha/airoha_eth.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index 59001fd4b6f7..fac2aaefffff 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c

@@ -2504,8 +2504,7 @@ static int airoha_tc_setup_qdisc_ets(struct net_device *dev,
 	if (opt->parent == TC_H_ROOT)
 		return -EINVAL;
 
-	channel = TC_H_MAJ(opt->handle) >> 16;
-	channel = channel % AIROHA_NUM_QOS_CHANNELS;
+	channel = TC_H_MIN(opt->parent) % AIROHA_NUM_QOS_CHANNELS;
 
 	switch (opt->command) {
 	case TC_ETS_REPLACE:

---
base-commit: e13caf1c26587434f0b768193100440939c0fb91
change-id: 20260704-airoha-ets-handle-fix-6c166de3d396

Best regards,
-- 
Lorenzo Bianconi [off-list ref]