[Spice-devel] Questions about Spice pv domUs

[Stefano Stabellini]

On Thu, 7 Nov 2013, Fabio Fantoni wrote:
> Il 06/11/2013 18:16, Stefano Stabellini ha scritto:
> > On Tue, 5 Nov 2013, Fabio Fantoni wrote:
> > > Il 30/09/2013 16:56, Fabio Fantoni ha scritto:
> > > > I'm trying to implement basic spice support on xen pv domUs.
> > > > 
> > > > Test seems ok on Ubuntu 12.04 pv domU except mouse which is not visible.
> > > > I also tried agent-mouse=off on qemu spice options but is not working or
> > > > maybe spicy (from spice-gtk 0.20) has problem in this case (option to
> > > > grab
> > > > mouse is already enabled).
> > > > I can't add vdagent for now on pv because it hasn't  pci support.
> > > > Are there xen parts which may give problem with mouse or couldn't be a
> > > > xen
> > > > related problem?
> > Given that PCI and USB buses are both missing in PV guests, I guess that
> > the issue might be that spice assumes that the mouse is somehow emulated
> > by a USB device? I think it could be difficult to disentangle spice
> > support from usb/pci.
> > You could try to run only the mouse part of the xenfb protocol to get
> > mouse support.
> > 
> > BTW where are you running the spice backend? Is it a standalone daemon?
> > 
> 
> For now I did only fast test forcing qemu parameters for pv dom's on libxl
> code with the same spice paramters used for hvm domUs.
> On first test was not working, then I added xenfb vga, and the screen works
> but mouse not.

Is it possible that you are actually not using spice at all, but just
using straight xenfb?


> > > > Qemu parameters on my test was:
> > > > > libxl: debug: libxl_dm.c:1282:libxl__spawn_local_dm: Spawning
> > > > > device-model
> > > > > /usr/lib/xen/bin/qemu-system-i386 with arguments:
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:
> > > > > /usr/lib/xen/bin/qemu-system-i386
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm: -xen-domid
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   19
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -chardev
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:
> > > > > socket,id=libxl-cmd,path=/var/run/xen/qmp-libxl-19,server,nowait
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -mon
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:
> > > > > chardev=libxl-cmd,mode=control
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm: -nodefaults
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm: -xen-attach
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -name
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   PRECISE
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -k
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   it
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -spice
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:
> > > > > port=6002,tls-port=0,addr=0.0.0.0,disable-ticketing,agent-mouse=off
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -vga
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   xenfb
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -M
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   xenpv
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   -m
> > > > > libxl: debug: libxl_dm.c:1284:libxl__spawn_local_dm:   1025
> > > > I have also another question for qemu developers: I tried to change qemu
> > > > -vga parameter to -device but isn't working and I not found nothing on
> > > > docs
> > > > or man. Is xenfb available with new qemu parameter -device?
> > As I replied in the other email, xenfb is configured and initialized via
> > xenstore. Why do you want a command line parameter for it?
> 
> I tried to do fast greps without find active code about xenfb.
> Can you tell me what I must search for find the new part about xenfb please?

The xenfb code is here:

hw/display/xenfb.c

It is registered here:

hw/i386/xen_machine_pv.c:xen_init_pv