Re: [GIT PULL] remove xend for 4.5 (Was: Re: [PATCH] MAINTAINERS: Exclude xend from toolstack maintainers entry)

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, Mar 31, 2014 at 02:13:31PM +0100, George Dunlap wrote:
> On 03/28/2014 05:09 PM, Konrad Rzeszutek Wilk wrote:
> >On Thu, Mar 27, 2014 at 11:08:47AM +0000, George Dunlap wrote:
> >>On Thu, Mar 27, 2014 at 11:00 AM, Ian Campbell <Ian.Campbell@citrix.com> wrote:
> >>>On Thu, 2014-03-20 at 14:02 +0000, Ian Campbell wrote:
> >>>>On Thu, 2014-03-20 at 13:32 +0000, Jan Beulich wrote:
> >>>>>  Which reminds me - didn't you want to rip out xend
> >>>>>right away after 4.4 (which would render pointless the patch
> >>>>>here)?
> >>>>I still want to do it before 4.5, this is more of a short term thing
> >>>>because people were sending me patches right now.
> >>>>
> >>>>Step one of the removal is to stop osstest from testing xend, I sent a
> >>>>patch for that a week or two ago.
> >>>That patch is now in place in the production osstest. So I propose the
> >>>following pull request (since the actual patch is nearly 3M in size,
> >>>even the diffstat here is bigger than most patches!).
> >>On my list of dependencies for removing xend, I have the following:
> >>
> >>* xend still in tree (x)
> >>  - xl list -l on a dom0-only system
> >>  - xl list -l doesn't contain tty console port
> >>  - xl Alternate transport support for migration*
> >>  - xl PVSCSI support
> >>  - xl PVUSB support
> >>  - xl support for vnc and vnclisten options with PV guests
> >I don't really like adding more of 'xend has this' to the list, but
> >Jan discovered that 'xend' was using the group assigment hypercall for
> >PCI devices while 'xl' is not doing that.
> >That hypercall has certain benefits - you can use it to figure out if
> >all of the PCI devices underneath a bridge are assigned to one
> >guest and not shared amongts the guests.
> 
> I'm copying this into my roadmap list (to hand on to the next
> release coordinator, whoever he or she may be).  Are there any
> references you can give for this?

It kind of started with this thread:
http://lists.xen.org/archives/html/xen-devel/2014-03/msg01053.html

And then Jan clued me in (http://lists.xen.org/archives/html/xen-devel/2014-03/msg01101.html)
and that we could use this group assigment as a way to fix this
problem. That is since each PCI bridge and its devices underneath
would have a group id - you just assign it that group and the
VT-d/AMD-VI would go through and setup contexts for all possible
BDFs underneath.

> 
>  -George