From: Leon Romanovsky <leon@kernel.org>
To: Ka-Cheong Poon <ka-cheong.poon@oracle.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>, linux-rdma@vger.kernel.org
Subject: Re: RDMA subsystem namespace related questions (was Re: Finding the namespace of a struct ib_device)
Date: Wed, 7 Oct 2020 14:16:36 +0300 [thread overview]
Message-ID: <20201007111636.GD3678159@unreal> (raw)
In-Reply-To: <ad892ef5-9b86-2e75-b0f8-432d8e157f60@oracle.com>
On Wed, Oct 07, 2020 at 04:38:45PM +0800, Ka-Cheong Poon wrote:
> On 10/6/20 8:46 PM, Jason Gunthorpe wrote:
> > On Tue, Oct 06, 2020 at 05:36:32PM +0800, Ka-Cheong Poon wrote:
> >
> > > > > > Kernel modules should not be doing networking unless commanded to by
> > > > > > userspace.
> > > > >
> > > > > It is still not clear why this is an issue with RDMA
> > > > > connection, but not with general kernel socket. It is
> > > > > not random networking. There is a purpose.
> > > >
> > > > It is a problem with sockets too, how do the socket users trigger
> > > > their socket usages? AFAIK all cases originate with userspace
> > >
> > > A user starts a namespace. The module is loaded for servicing
> > > requests. The module starts a listener. The user deletes
> > > the namespace. This scenario will have everything cleaned up
> > > properly if the listener is a kernel socket. This is not the
> > > case with RDMA.
> >
> > Please point to reputable code in upstream doing this
>
>
> It is not clear what "reputable" here really means. If it just
> means something in kernel, then nearly all, if not all, Internet
> protocols code in kernel create a control kernel socket for every
> network namespaces. That socket is deleted in the per namespace
> exit function. If it explicitly means listening socket, AFS and
> TIPC in kernel do that for every namespaces. That socket is
> deleted in the per namespace exit function.
>
> It is very common for a network protocol to have something like
> this for protocol processing. It is not clear why RDMA subsystem
> behaves differently and forbids this common practice. Could you
> please elaborate the issues this practice has such that the RDMA
> subsystem cannot support it?
Just curious, are we talking about theoretical thing here or do you
have concrete and upstream ULP code to present?
Thanks
>
>
>
> --
> K. Poon
> ka-cheong.poon@oracle.com
>
>
next prev parent reply other threads:[~2020-10-07 11:16 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-03 14:02 Finding the namespace of a struct ib_device Ka-Cheong Poon
2020-09-03 17:39 ` Jason Gunthorpe
2020-09-04 4:01 ` Ka-Cheong Poon
2020-09-04 11:32 ` Jason Gunthorpe
2020-09-04 14:02 ` Ka-Cheong Poon
2020-09-06 7:44 ` Leon Romanovsky
2020-09-07 3:33 ` Ka-Cheong Poon
2020-09-07 7:18 ` Leon Romanovsky
2020-09-07 8:24 ` Ka-Cheong Poon
2020-09-07 9:04 ` Leon Romanovsky
2020-09-07 9:28 ` Ka-Cheong Poon
2020-09-07 10:22 ` Leon Romanovsky
2020-09-07 13:48 ` Ka-Cheong Poon
2020-09-29 16:57 ` RDMA subsystem namespace related questions (was Re: Finding the namespace of a struct ib_device) Ka-Cheong Poon
2020-09-29 17:40 ` Jason Gunthorpe
2020-09-30 10:32 ` Ka-Cheong Poon
2020-10-02 14:04 ` Jason Gunthorpe
2020-10-05 10:27 ` Ka-Cheong Poon
2020-10-05 13:16 ` Jason Gunthorpe
2020-10-05 13:57 ` Ka-Cheong Poon
2020-10-05 14:25 ` Jason Gunthorpe
2020-10-05 15:02 ` Ka-Cheong Poon
2020-10-05 15:45 ` Jason Gunthorpe
2020-10-06 9:36 ` Ka-Cheong Poon
2020-10-06 12:46 ` Jason Gunthorpe
2020-10-07 8:38 ` Ka-Cheong Poon
2020-10-07 11:16 ` Leon Romanovsky [this message]
2020-10-08 10:22 ` Ka-Cheong Poon
2020-10-08 10:36 ` Leon Romanovsky
2020-10-08 11:08 ` Ka-Cheong Poon
2020-10-08 16:08 ` Jason Gunthorpe
2020-10-08 16:21 ` Chuck Lever
2020-10-08 16:46 ` Jason Gunthorpe
2020-10-09 4:49 ` Ka-Cheong Poon
2020-10-09 14:39 ` Jason Gunthorpe
2020-10-09 14:48 ` Chuck Lever
2020-10-09 14:57 ` Jason Gunthorpe
2020-10-09 15:00 ` Chuck Lever
2020-10-09 15:07 ` Jason Gunthorpe
2020-10-09 15:27 ` Chuck Lever
2020-10-09 15:34 ` Jason Gunthorpe
2020-10-09 15:52 ` Chuck Lever
2020-10-12 8:20 ` Ka-Cheong Poon
2020-10-16 18:54 ` Jason Gunthorpe
2020-10-16 20:49 ` Chuck Lever
2020-10-19 18:31 ` Jason Gunthorpe
2020-10-07 12:28 ` Jason Gunthorpe
2020-10-08 10:49 ` Ka-Cheong Poon
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