On 07/10/2014 05:37 AM, Daniel Borkmann wrote: > On 07/10/2014 11:02 AM, David Laight wrote: >> From: Neil Horman >> ... >>>> No there is not direct overlap between the two. However, as Michael pointed out, >>>> there is a new option to control SCTP_RCVINFO. So would could add a deprecation >>>> warning to the over SCTP_EVENTS option and carry SCTP_SNDRCVINFO with it. >>>> Once SCTP_EVENTS goes away so can SCTP_SNDRCVINFO. >>>> >>> Ok, so we should still consider deprecation warnings then. Daniel, what about >>> ratelimited warnings with pids included then? >> >> Can you defer any deprecation warnings for a few kernel versions? >> This gives time for applications to be recoded. > > I am fine either way, adding the warning a bit later seems fine, too. > > Right now, even in-kernel users like dlm would hit it if we include > it immediately. > > Otherwise, I'll just add something like the below ... > > diff --git a/net/sctp/socket.c b/net/sctp/socket.c > index d95a50c..6a0e5a4 100644 > --- a/net/sctp/socket.c > +++ b/net/sctp/socket.c > @@ -2205,8 +2205,13 @@ static int sctp_setsockopt_events(struct sock *sk, char __user > *optval, > if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen)) > return -EFAULT; > > - /* > - * At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT, > + if (sctp_sk(sk)->subscribe.sctp_data_io_event) > + pr_warn_ratelimited(DEPRECATED "%s (pid %d) " > + "Requested SCTP_SNDRCVINFO event.\n" > + "Use SCTP_RCVINFO through SCTP_RECVRCVINFO option instead.\n", > + current->comm, task_pid_nr(current)); > + > + /* At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT, > * if there is no data to be sent or retransmit, the stack will > * immediately send up this notification. > */ > This is OK for step 1. Once we implement SCTP_EVENT, we can cover the rest of the events. -vlad >> Including argv[0] (even just the exec-time value) is much more use than the pid. >> >> Actually this is 'right PITA' for an application. >> A program binary that needs to work with old and new kernels will have to >> try the new option, and if it fails fall back to the old one, and then >> conditionally create/inspect the cmsg data. >> I can't actually imagine anyone bothering! >> >> Our sctp code is actually in a kernel module, so we can look at the kernel >> version when (part of) the driver is compiled on the target system. >> >> David >> >> >> -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
