Xen devel - Mar 2013 - [PATCH] libxl: Add spice vdagent support for upstream qemu

- Enable vdagent on upstream qemu if spice is used.

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
---
 tools/libxl/libxl_dm.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
index a8a36d7..110f1dc 100644
--- a/tools/libxl/libxl_dm.c
+++ b/tools/libxl/libxl_dm.c
@@ -427,6 +427,10 @@ static char ** libxl__build_device_model_args_new(libxl__gc
*gc,
 
             flexarray_append(dm_args, "-spice");
             flexarray_append(dm_args, spiceoptions);
+            flexarray_vappend(dm_args, "-device",
"virtio-serial", "-chardev",
+                "spicevmc,id=vdagent,name=vdagent",
"-device",
+               
"virtserialport,chardev=vdagent,name=com.redhat.spice.0",
+                NULL);
         }
 
         switch (b_info->u.hvm.vga.kind) {
-- 
1.7.9.5

fantonifabio@tiscali.it writes ("[PATCH] libxl: Add spice vdagent support
for upstream qemu"):
> - Enable vdagent on upstream qemu if spice is used.
Forgive my ignorance, but what is this ?  Can you point me to some
docs or something ?

Thanks,
Ian.

Fabio Fantoni writes ("Re: [PATCH] libxl: Add spice vdagent support for
upstream qemu"):
> Spice for now not have very good documentation, his documentation is 
> mainly on kvm even if is working also without kvm, I used vdagent for 
> one year manually without problem on xen, it provide some very useful (I 
> think essential) functions.
> For small and fast description about it probably the description of this 
> package is good:
> http://packages.debian.org/wheezy/spice-vdagent
Hmmm.

Does this then pass more things through to the guest ?  Is there any
security risk to the host ?  This is I''m afraid unclear, and is why
I''m hesitating.

Ian.

On Tue, 2013-03-26 at 17:42 +0000, Fabio Fantoni wrote:
> Il 26/03/2013 17:30, Ian Jackson ha scritto:
> > Fabio Fantoni writes ("Re: [PATCH] libxl: Add spice vdagent
support for upstream qemu"):
> >> Spice for now not have very good documentation, his documentation
is
> >> mainly on kvm even if is working also without kvm, I used vdagent
for
> >> one year manually without problem on xen, it provide some very
useful (I
> >> think essential) functions.
> >> For small and fast description about it probably the description
of this
> >> package is good:
> >> http://packages.debian.org/wheezy/spice-vdagent
> > Hmmm.
> >
> > Does this then pass more things through to the guest ?  Is there any
> > security risk to the host ?  This is I''m afraid unclear, and
is why
> > I''m hesitating.
> I think there aren''t security risk for host because these are only
> operation done between spice client and guest os if this channel is 
> present on qemu of guest and agent is installed on guest os.
Looks like (from http://spice-space.org/page/Whiteboard/AgentProtocol)
this protocol supports things like clipboard sharing, which may or may
not be what the person starting the VM wants depending on who they are
allowing to access the VM remotely.

So I think at a minimum this needs to only be optionally added to the
guest, and probably to default to off even if spice is enabled.

Ian.