Re: [RFC PATCH 1/1] Add a usbredir kernel module to remotely connect USB devices over IP.

Greg KH
2015-07-22T14:34:12Z

On Wed, Jul 22, 2015 at 09:03:53AM -0500, Jeremy White wrote:
> On 07/09/2015 05:06 AM, Alex Elsayed wrote:
> >Alan Stern wrote:
> >
> >>On Mon, 6 Jul 2015, Jeremy White wrote:
> >>
> >>>Anything else fundamental to usbip that should inform the design of a
> >>>usbredir driver? usbip appears to be based off a 2004 vintage of
> >>>dummy_hcd. I'll look thoughtfully at the current dummy_hcd; please let
> >>>me know if there is anything else I should consider.
> >>
> >>One thing that springs to mind is USB-3 streams. When dummy-hcd was
> >>expanded to include USB-3, that was the major new ingredient.
> >
> >Another thing that comes to mind is that the USB-IF has its own official
> >standard for this kind of thing now, called Media-Agnostic USB[1]. In
> >November of 2014 a driver[2] was posted, followed by a second version[3],
> >and it is apparently being refined inside Intel[4].
> >
> >[1]
> >http://www.usb.org/developers/docs/devclass_docs/Media_Agnostic_USB_v1.0.zip
> >[2] http://thread.gmane.org/gmane.linux.kernel/1820297
> >[3] http://thread.gmane.org/gmane.linux.drivers.driver-project.devel/60498
> >[4] http://article.gmane.org/gmane.linux.drivers.driver-project.devel/60757
>
> Thanks for the pointer, Alex.
>
> I spent some time with the spec and their proposed code. It does seem
> plausible that XSpice could use a mausb/usbredir protocol converter. So if
> there was a mausb kernel module, I could potentially implement support in
> XSpice in user space and not need a usbredir module.
>
> I sent an email to the two developers at Intel to ask if there had been any
> further progress and if I could collaborate with them. I have not heard
> back.
>
> The MA spec is substantial and seems well thought out. But the usbredir
> protocol has the virtue of being relatively mature - it's 5 years old, with
> code in daily use.
>
> At this point it seems the best path forward is to continue work on the
> usbredir kernel module, which I will do unless I get some new information.

Please work with the existing people, or with the existing spec, I don't
want to be adding multiple versions of this type of protocol to the
kernel. As it is, I really don't even want to take your code, given
that usbip is already there. Ignoring it isn't ok.

thanks,

greg k-h