Re: [PATCH net v2] net: mana: Ring doorbell at 4 CQ wraparounds

patchwork-bot+netdevbpf
2026-02-28T03:40:04Z

Hello:

This patch was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Thu, 26 Feb 2026 11:28:33 -0800 you wrote:
> MANA hardware requires at least one doorbell ring every 8 wraparounds
> of the CQ. The driver rings the doorbell as a form of flow control to
> inform hardware that CQEs have been consumed.
>
> The NAPI poll functions mana_poll_tx_cq() and mana_poll_rx_cq() can
> poll up to CQE_POLLING_BUFFER (512) completions per call. If the CQ
> has fewer than 512 entries, a single poll call can process more than
> 4 wraparounds without ringing the doorbell. The doorbell threshold
> check also uses ">" instead of ">=", delaying the ring by one extra
> CQE beyond 4 wraparounds. Combined, these issues can cause the driver
> to exceed the 8-wraparound hardware limit, leading to missed
> completions and stalled queues.
>
> [...]

Here is the summary with links:
- [net,v2] net: mana: Ring doorbell at 4 CQ wraparounds
https://git.kernel.org/netdev/net/c/dabffd08545f

You are awesome, thank you!
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