Re: [PATCH net v2] net: ethernet: mediatek: preserve sibling PPE bindings

[Simon Horman <horms@kernel.org>]

On Thu, Oct 29, 2026 at 06:05:17PM -0700, Alexander Goodkind wrote:
> __mtk_ppe_check_skb() clears entry->hash for flows bound to other
> hardware slots in the same software hash bucket. mtk_flow_offload_stats()
> then skips their hardware counter updates. L2 cleanup also frees sibling
> subflows without invalidating their hardware rules.
> 
> Restrict both cleanup paths to entries assigned to the inspected slot.
> 
> Two UDP trials reproduced the counter failure on a GL-MT3000/MT7981
> running unmodified OpenWrt 25.12.5 with Linux 6.12.94:
> 
> 1. Start a UDP connection.
> 2. Add a control connection in a different hash bucket.
> 3. Add a connection in the first connection's hash bucket.
> 
> AI code review of the original patch identified the cleanup problem
> in L2 subflows.
> 
> Full ARM64 builds with allmodconfig and allyesconfig passed before
> and after the patch using GCC 14.2.0 and W=1, without new warnings.
> The builds used CONFIG_WERROR=n because the unmodified ARM64 kernel
> already emits warnings. Hardware testing has not run for this revision.
> 
> Fixes: c4f033d9e03e ("net: ethernet: mtk_eth_soc: rework hardware flow table management")
> Fixes: 33fc42de3327 ("net: ethernet: mtk_eth_soc: support creating mac address based offload entries")
> Link: https://github.com/openwrt/openwrt/pull/26107
> Assisted-by: LLM
> Signed-off-by: Alexander Goodkind <alex@goodkind.io>
> ---
> Changes in v2:
> - Apply the slot check to L2 subflow cleanup as well.
> - Add the Fixes tag for L2 offload support.
> 
> V1: https://lore.kernel.org/netdev/20261023012529.5994-1-alex@goodkind.io/
> 
> Codex assisted with investigating the counters and preparing the patch.

Thanks for the updates.

Reviewed-by: Simon Horman <horms@kernel.org>