On 23/05/2022 17:21, liuyacan@xxxxxxxxxxxxxxxx wrote: >>>> 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()? >> >> What I had in mind was to eventually call sock_put() in __smc_release() even if sk->sk_state == SMC_INIT >> (currently the extra check in the if() for sk->sk_state != SMC_INIT prevents the sock_put()), but only >> when it is sure that we actually reached the sock_hold() in smc_connect() before. >> >> But maybe we find out that the sock_hold() is not needed for fallback sockets, I don't know... > > I do think the sock_hold()/sock_put() for smc->sk is a bit complicated, Emm, I'm not sure if it > can be simplified.. > > In fact, I'm sure there must be another ref count issue in my environment,but I haven't caught it yet. > Can you check my latest mail from a minute ago in thread "Re: [PATCH net-next v2] net/smc: align the connect behaviour with TCP" I think this answer also affects our discussion.
