On Mon, Mar 01, 2021 at 10:54:21AM -0600, Bob Pearson wrote: > I agree that ib_device_get/put is attempting to solve a problem that it not > really very critical since ib_device is very unlikely to be shut down in the > middle of a data transfer. The driver never worried about this for years. > But now that it's been put on the table it should be done right. A data packet > arriving is completely independent of the verbs API which *could* delete all the > QPs and shut down the HCA while it was wondering around the universe or worse > yet while the packet is being processed. If driver shutdown can guarentee that all pointers involved in multicast are revoked before shutdown can finish then you don't need this refcounting. It was only brought up because the API that returns the ib_device from the netdev requires the refcounts as it is general purpose Jason
