Re: [Xen-devel] [PATCH net-next] xen-netback: get rid of old udev related code

[JÃrgen GroÃ]

On 12.12.19 20:05, David Miller wrote:
> From: Paul Durrant <pdurrant@xxxxxxxxxx>
> Date: Thu, 12 Dec 2019 13:54:06 +0000
>
> > In the past it used to be the case that the Xen toolstack relied upon
> > udev to execute backend hotplug scripts. However this has not been the
> > case for many releases now and removal of the associated code in
> > xen-netback shortens the source by more than 100 lines, and removes much
> > complexity in the interaction with the xenstore backend state.
> >
> > NOTE: xen-netback is the only xenbus driver to have a functional uevent()
> >        method. The only other driver to have a method at all is
> >        pvcalls-back, and currently pvcalls_back_uevent() simply returns 0.
> >        Hence this patch also facilitates further cleanup.
> >
> > Signed-off-by: Paul Durrant <pdurrant@xxxxxxxxxx>
>
> If userspace ever used this stuff, I seriously doubt you can remove this
> even if it hasn't been used in 5+ years.

Hmm, depends.

This has been used by Xen tools in dom0 only. If the last usage has been
in a Xen version which is no longer able to run with current Linux in
dom0 it could be removed. But I guess this would have to be a rather old
version of Xen (like 3.x?).

Paul, can you give a hint since which Xen version the toolstack no
longer relies on udev to start the hotplug scripts?


Juergen