Re: [PATCH] io_uring/zcrx: requeue multishot receives stopped by a local resource

[Pavel Begunkov <asml.silence@gmail.com>]

On 9/23/26 10:20, Junyuan Feng wrote:
> A multishot RECV_ZC can go idle with unread TCP data when a receiver-local
> resource runs out. An empty copy-fallback niov freelist returns -ENOMEM;
> a full CQ returns -ENOSPC. After partial progress the stop reason is
> lost: io_zcrx_copy_chunk() and io_zcrx_recv_skb() report the copied
> bytes, and tcp_read_sock() drops an error from a later call once earlier
> data was consumed. The edge-triggered request is then not requeued, so
> it cannot consume the remaining data until another socket event arrives.
> 
> Record in io_zcrx_recv_skb() when a walk stops before consuming the
> length it was offered, and requeue if the pass still returned data. The
> failed chunk is first on the next pass. The resource is usually still
> exhausted by then, so that pass fails at once and ends the request with
> an error CQE, which the application must handle by re-arming. The
> request does not spin, and the stall becomes a visible error. Keep the
> existing skb limit and SOCK_DONE handling.

Looks good

Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>

-- 
Pavel Begunkov