Re: [PATCH v3 3/8] net/handshake: Ensure the request is destructed on completion

[Hannes Reinecke <hare@suse.de>]

On 10/7/25 03:22, Alistair Francis wrote:
> On Mon, Oct 6, 2025 at 4:16 PM Hannes Reinecke <hare@suse.de> wrote:
>>
>> On 10/3/25 06:31, alistair23@gmail.com wrote:
>>> From: Alistair Francis <alistair.francis@wdc.com>
>>>
>>> To avoid future handshake_req_hash_add() calls failing with EEXIST when
>>> performing a KeyUpdate let's make sure the old request is destructed
>>> as part of the completion.
>>>
>>> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
>>> ---
>>> v3:
>>>    - New patch
>>>
>>>    net/handshake/request.c | 2 ++
>>>    1 file changed, 2 insertions(+)
>>>
>>> diff --git a/net/handshake/request.c b/net/handshake/request.c
>>> index 0d1c91c80478..194725a8aaca 100644
>>> --- a/net/handshake/request.c
>>> +++ b/net/handshake/request.c
>>> @@ -311,6 +311,8 @@ void handshake_complete(struct handshake_req *req, unsigned int status,
>>>                /* Handshake request is no longer pending */
>>>                sock_put(sk);
>>>        }
>>> +
>>> +     handshake_sk_destruct_req(sk);
>>>    }
>>>    EXPORT_SYMBOL_IF_KUNIT(handshake_complete);
>>>
>> Curious.
>> Why do we need it now? We had been happily using the handshake mechanism
>> for quite some time now, so who had been destroying the request without
>> this patch?
> 
> Until now a handshake would only be destroyed on a failure or when a
> sock is freed (via the sk_destruct function pointer).
> handshake_complete() is only called on errors, not a successful
> handshake so it doesn't remove the request.
> 
> Note that destroying is mostly just removing the entry from the hash
> table with rhashtable_remove_fast(). Which is what we need to be able
> to submit it again.
> 

And we really should've done that in the first place.
Thanks for the explanation.

Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

Hannes--
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
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