On Mon, Nov 22, 2021 at 05:47:43PM +0100, Karsten Graul wrote: > On 17/11/2021 17:19, Karsten Graul wrote: > > On 16/11/2021 04:30, Tony Lu wrote: > >> We found an issue when replacing TCP with SMC. When the actively closed > >> peer called close() in userspace, the clcsock of peer doesn't enter TCP > >> active close progress, but the passive closed peer close it first, and > >> enters TIME_WAIT state. It means the behavior doesn't match what we > >> expected. After reading RFC7609, there is no clear description of the > >> order in which we close clcsock during close progress. > > > > Thanks for your detailed description, it helped me to understand the problem. > > Your point is that SMC sockets should show the same behavior as TCP sockets > > in this situation: the side that actively closed the socket should get into > > TIME_WAIT state, and not the passive side. I agree with this. > > Your idea to fix it looks like a good solution for me. But I need to do more > > testing to make sure that other SMC implementations (not Linux) work as > > expected with this change. For example, Linux does not actively monitor the > > clcsocket state, but if another implementation would do this it could happen > > that the SMC socket is closed already when the clcsocket shutdown arrives, and > > pending data transfers are aborted. > > > > I will respond to your RFC when I finished my testing. > > > > Thank you. > > > > Testing and discussions are finished, the patch looks good. > Can you please send your change as a patch to the mailing list? Thanks for your advice and testing. I will send it soon. Cheers, Tony Lu