>>> On 09.11.15 at 10:51, <paul.durr...@citrix.com> wrote: >> -----Original Message----- >> From: Andrew Cooper [mailto:andrew.coop...@citrix.com] >> Sent: 06 November 2015 18:08 >> To: Paul Durrant; xen-de...@lists.xenproject.org >> Cc: Keir (Xen.org); Ian Campbell; Tim (Xen.org); Ian Jackson; Jan Beulich >> Subject: Re: [Xen-devel] [PATCH 3/4] docs: Document xenstore paths for >> domain hotplug features >> >> On 06/11/15 17:21, Paul Durrant wrote: >> > Without some indication from an HVM domain it is not possible for a >> > toolstack to know whether instantiation of a new vbd or vif should >> > result in a new PV device of the appropriate type being instantiated >> > in a guest. (In other words whether PV drivers are present and >> > functioning). >> > >> > This patch document two paths which vif and vbd frontend drivers can >> > use to advertise their ability to respond to new vif or vbd >> > instantiations. >> > >> > Signed-off-by: Paul Durrant <paul.durr...@citrix.com> >> > Cc: Ian Campbell <ian.campb...@citrix.com> >> > Cc: Ian Jackson <ian.jack...@eu.citrix.com> >> > Cc: Jan Beulich <jbeul...@suse.com> >> > Cc: Keir Fraser <k...@xen.org> >> > Cc: Tim Deegan <t...@xen.org> >> > --- >> > docs/misc/xenstore-paths.markdown | 12 ++++++++++++ >> > 1 file changed, 12 insertions(+) >> > >> > diff --git a/docs/misc/xenstore-paths.markdown b/docs/misc/xenstore- >> paths.markdown >> > index 7701632..9e98d6f 100644 >> > --- a/docs/misc/xenstore-paths.markdown >> > +++ b/docs/misc/xenstore-paths.markdown >> > @@ -387,6 +387,18 @@ A domain writable path. Available for arbitrary >> domain use. >> > A domain may write version information for PV driver $NAME using >> > this path. >> > >> > +#### ~/feature/hotplug/vif = ("0"|"1") [w,HVM] >> > + >> > +An HVM domain can indicate to a toolstack that it is capable >> > +of responding to instantiation of a new vif by bringing online a >> > +new PV network device without the need for a reboot. >> > + >> > +#### ~/feature/hotplug/vbd = ("0"|"1") [w,HVM] >> > + >> > +An HVM domain can indicate to a toolstack that it is capable >> > +of responding to instantiation of a new vbd by bringing online a >> > +new PV block device without the need for a reboot. >> >> These flags are not inherently restricted to HVM guests. Therefore, I >> would avoid specifying them as such. (It is quite possible for a PV >> guest not to be able to hotplug a vbd for example.) > > I wasn't sure that was true. My belief was that all pure PV guests would > have frontends handling hot attach. I'm happy to drop the HVM tag in v2 > though.
With intermediate steps between HVM and PVH planned to become possible, I think not overly limiting the scope of such entries would indeed desirable. Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
