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To:     kgraul@linux.ibm.com
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Subject: Re: [PATCH v2 net] net/smc: postpone sk_refcnt increment in connect()
Date:   Mon, 23 May 2022 22:19:05 +0800
Message-Id: <20220523141905.2791310-1-liuyacan@corp.netease.com>
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> This is a rather unusual problem that can come up when fallback=true BEFORE smc_connect()
> is called. But nevertheless, it is a problem.
> 
> Right now I am not sure if it is okay when we NOT hold a ref to smc->sk during all fallback
> processing. This change also conflicts with a patch that is already on net-next (3aba1030).

Do you mean put the ref to smc->sk during all fallback processing unconditionally and remove 
the fallback branch sock_put() in __smc_release()?

> With the new patch on net-next it would also be possible to detect in __smc_release() that
> the socket is in state sk->sk_state == SMC_INIT but the sock->state is SS_CONNECTING or 
> SS_CONNECTED and call sock_put() in this case.
> What do you think?

Oh, I didn't notice this patch on net-next. Emm, I think I need to do some testing with this 
patch.

Thank you.