* Leon Romanovsky (leon@xxxxxxxxxx) wrote:
> On Mon, May 17, 2021 at 11:06:35AM +0100, Dr. David Alan Gilbert wrote:
> > Hi,
> > Is 'rdma_get_cm_event's behaviour in initialising **event
> > defined in the error case?
> > We don't see anything in the manual page, my reading of the
> > code is it's not set/changed in the case of failure - but is
> > that defined?
> > It would be good if the manpage could explicitly state it.
>
> AFAIK, the general practice do not rely on any output argument if
> function returns an error and I'm not sure that the man update is
> needed.
The case we had was whether we needed to clean up or not in the error
case; the original code in qemu was:
2496 ret = rdma_get_cm_event(rdma->channel, &cm_event);
2497 if (ret) {
2498 perror("rdma_get_cm_event after rdma_connect");
2499 ERROR(errp, "connecting to destination!");
2500 rdma_ack_cm_event(cm_event);
2501 goto err_rdma_source_connect;
2502 }
and Li spotted that rdma_ack_cm_event would seg in the case
rdma_get_cm_event failed.
While I agree on not relying on an output; without a definition you're
stuck between not knowing if you're leaking an event that should
have been cleaned up.
Dave
> Thanks
>
> >
> > Dave
> > --
> > Dr. David Alan Gilbert / dgilbert@xxxxxxxxxx / Manchester, UK
> >
>
--
Dr. David Alan Gilbert / dgilbert@xxxxxxxxxx / Manchester, UK
