On 28/03/2022 08:10, Wen Gu wrote:
> The current autocork algorithms will delay the data transmission
> in BH context to smc_release_cb() when sock_lock is hold by user.
>
> So there is a possibility that when connection is being actively
> closed (sock_lock is hold by user now), some corked data still
> remains in sndbuf, waiting to be sent by smc_release_cb(). This
> will cause:
>
> - smc_close_stream_wait(), which is called under the sock_lock,
> has a high probability of timeout because data transmission is
> delayed until sock_lock is released.
>
> - Unexpected data sends may happen after connction closed and use
> the rtoken which has been deleted by remote peer through
> LLC_DELETE_RKEY messages.
>
> So this patch will try to send out the remaining corked data in
> sndbuf before active close process, to ensure data integrity and
> avoid unexpected data transmission after close.
>
> Reported-by: Guangguan Wang <guangguan.wang@xxxxxxxxxxxxxxxxx>
> Fixes: 6b88af839d20 ("net/smc: don't send in the BH context if sock_owned_by_user")
> Signed-off-by: Wen Gu <guwen@xxxxxxxxxxxxxxxxx>
> ---
Thank you,
Acked-by: Karsten Graul <kgraul@xxxxxxxxxxxxx>
