Re: [PATCH v5 1/4] RDMA/nldev: Add dellink function pointer

[Zhu Yanjun <yanjun.zhu@linux.dev>]

在 2026/3/11 19:04, David Ahern 写道:
> On 3/11/26 4:01 PM, Yanjun.Zhu wrote:
>
>> Got it. The commit log explains how the netdev_notifier mechanism is
> netdev notifiers are the NETDEV_UNREGISTER and friends. This dellink
> handler is not related to that; this is an IB stack thing when the rxe
> link is removed.
>
>> used to clean up the related resources.
>>
>> In the source code, additional comments have been added to explain how
>> the dellink operation for rxe is triggered. For iWARP, this change
>> should not make any difference because iWARP does not implement the
>> dellink function.
>>
>> The commit is shown below. Please take a look and share your comments.
>> If you agree, I will send out the latest commits out very soon.
>>
>>  From c05038dcdf69c5985837736a8926ba76d9f3e8e4 Mon Sep 17 00:00:00 2001
>> From: Zhu Yanjun <yanjun.zhu@linux.dev>
>> Date: Fri, 23 Sep 2022 16:52:45 +0000
>> Subject: [PATCH 1/1] RDMA/nldev: Add dellink function pointer
>>
>> The newlink function pointer was previously added to support
>> dynamic RDMA link creation. In the RXE driver, this path creates
>> a transport socket listening on port 4791. Consequently, a dellink
>> function pointer is required to ensure these sockets are properly
>> closed when a user administratively removes a link via rdma link
>> delete <dev>.
>>
>> Furthermore, RXE does not rely solely on this nldev path for resource
>> management. It also monitors the underlying net_device state via a
>> registered netdev_notifier. The rxe_net_event callback serves as a
>> fallback mechanism to ensure that transport sockets are forcibly closed
>> and all resources are released even if dellink is not explicitly called
>> (e.g., if the parent NIC interface is removed or the driver is forcefully
>> unloaded).
> IMHO, this explanation belongs in the patch that implements dellink for rxe.
>
> This patch adds the handler to allow link implementations to cleanup any
> resources created by newklink as needed.
Thanks for the feedback. I agree that the detailed explanation of RXE's 
resource management (like sockets and notifiers) is more appropriate for 
the subsequent patch that implements the RXE dellink handler.

I will update the commit message for this patch to focus solely on the 
addition of the dellink infrastructure in the RDMA core, and move the 
RXE-specific details to the next patch in the series.

Zhu Yanjun

>
-- 
Best Regards,
Yanjun.Zhu