Hi Jason- > On Oct 9, 2020, at 10:39 AM, Jason Gunthorpe <jgg@xxxxxxxx> wrote: > > On Fri, Oct 09, 2020 at 12:49:30PM +0800, Ka-Cheong Poon wrote: >> As I mentioned before, this is a very serious restriction on how >> the RDMA subsystem can be used in a namespace environment by kernel >> module. The reason given for this restriction is that any kernel >> socket without a corresponding user space file descriptor is "rogue". >> All Internet protocol code create a kernel socket without user >> interaction. Are they all "rogue"? > > You should work with Chuck to make NFS use namespaces properly and > then you can propose what changes might be needed with a proper > justification. The NFS server code already uses namespaces for creating listener endpoints, already has a user space component that drives the creation of listeners, and already passes an appropriate struct net to rdma_create_id. As far as I am aware, it is namespace-aware and -friendly all the way down to rdma_create_id(). What more needs to be done? > The rules for lifetime on IB clients are tricky, and the interaction > with namespaces makes it all a lot more murky. I think what Ka-cheong is asking is for a detailed explanation of these lifetime rules so we can understand why rdma_create_id bumps the namespace reference count. -- Chuck Lever chucklever@xxxxxxxxx
