[Spice-devel] Questions about Spice pv domUs

[Fabio Fantoni]

Il 07/11/2013 16:25, Stefano Stabellini ha scritto:
> 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?
>

Yes, is spice on qemu, simply with xenfb as vga instead of stdvga that I 
use with hvm domUs for now.
About qxl vga (optimal for increase spice performance and more 
resolutions support), seems that requires other modifications/fix xen 
side that are not able to do :(
Latest debug that I tried if can be useful:
http://lists.xen.org/archives/html/xen-devel/2013-10/msg00016.html
Waiting for news about it I'm trying to implement at least the basic 
spice support on pv for use spice for both hvm and pv (atleast the part 
of domUs maintenance).


>>>>> 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

Thanks, then I must search on qemu code what xenstore parameters enable 
xenfb and after search on xen, right?