thr3ads.net - Xen devel - [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default [Jun 2011]

If this information is useful, please help other people find it:
Share via:

Stefano Stabellini

2011-Jun-24 16:29 UTC

[Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

PV on HVM drivers can connect to the vkbd device to receive mouse and
keyboard events from Qemu. The advantage over USB is that vkbd doesn''t
require frequent wakeups in Qemu.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

diff -r f17956fd6976 tools/libxl/libxl_create.c
--- a/tools/libxl/libxl_create.c	Fri Jun 17 16:10:48 2011 +0000
+++ b/tools/libxl/libxl_create.c	Fri Jun 24 16:19:29 2011 +0000
@@ -469,6 +469,7 @@ static int do_domain_create(libxl__gc *g
     }
     if (d_config->c_info.hvm) {
         libxl_device_console console;
+        libxl_device_vkb vkb;
 
         ret = init_console_info(&console, 0);
         if ( ret )
@@ -476,6 +477,11 @@ static int do_domain_create(libxl__gc *g
         libxl__device_console_add(gc, domid, &console, &state);
         libxl_device_console_destroy(&console);
 
+
+        memset(&vkb, 0x00, sizeof(vkb));
+        libxl_device_vkb_add(ctx, domid, &vkb);
+        libxl_device_vkb_destroy(&vkb);
+
         dm_info->domid = domid;
         ret = libxl__create_device_model(gc, dm_info,
                                         d_config->disks,
d_config->num_disks,

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Ian Campbell

2011-Jun-27 09:44 UTC

head link

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

On Fri, 2011-06-24 at 17:29 +0100, Stefano Stabellini
wrote:> PV on HVM drivers can connect to the vkbd device to receive mouse and
> keyboard events from Qemu. The advantage over USB is that vkbd
doesn''t
> require frequent wakeups in Qemu.
Do we need an unplug protocol in order to stop these frequent wakeups?

Do frontends/guests generally cope with two keyboards correctly?
(whatever correctly means, I guess it''s not obvious once you have a vfb
as well as emulated VGA).
> 
> Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> 
> diff -r f17956fd6976 tools/libxl/libxl_create.c
> --- a/tools/libxl/libxl_create.c	Fri Jun 17 16:10:48 2011 +0000
> +++ b/tools/libxl/libxl_create.c	Fri Jun 24 16:19:29 2011 +0000
> @@ -469,6 +469,7 @@ static int do_domain_create(libxl__gc *g
>      }
>      if (d_config->c_info.hvm) {
>          libxl_device_console console;
> +        libxl_device_vkb vkb;
>  
>          ret = init_console_info(&console, 0);
>          if ( ret )
> @@ -476,6 +477,11 @@ static int do_domain_create(libxl__gc *g
>          libxl__device_console_add(gc, domid, &console, &state);
>          libxl_device_console_destroy(&console);
>  
> +
> +        memset(&vkb, 0x00, sizeof(vkb));
> +        libxl_device_vkb_add(ctx, domid, &vkb);
> +        libxl_device_vkb_destroy(&vkb);
> +
>          dm_info->domid = domid;
>          ret = libxl__create_device_model(gc, dm_info,
>                                          d_config->disks,
d_config->num_disks,
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Ian Campbell

2011-Jun-27 12:14 UTC

head link

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

On Mon, 2011-06-27 at 13:14 +0100, Stefano Stabellini
wrote:> On Mon, 27 Jun 2011, Ian Campbell wrote:
> > On Fri, 2011-06-24 at 17:29 +0100, Stefano Stabellini wrote:
> > > PV on HVM drivers can connect to the vkbd device to receive mouse
and
> > > keyboard events from Qemu. The advantage over USB is that vkbd
doesn''t
> > > require frequent wakeups in Qemu.
> > 
> > Do we need an unplug protocol in order to stop these frequent wakeups?
> 
> No, we just need to disable USB. The only reason to have USB is to have
> USB tablet support (absolute mouse coordinates).
That means users need to be aware that they have the appropriate
frontends and manually edit their guest config?
> > Do frontends/guests generally cope with two keyboards correctly?
> > (whatever correctly means, I guess it''s not obvious once you
have a vfb
> > as well as emulated VGA).
> 
> Yes, without any problems. Having multiple vfbs would be more
> complicated but it is not part of this series.
OK

Ian.


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Stefano Stabellini

2011-Jun-27 12:14 UTC

head link

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

On Mon, 27 Jun 2011, Ian Campbell wrote:> On Fri, 2011-06-24 at 17:29 +0100, Stefano Stabellini wrote:
> > PV on HVM drivers can connect to the vkbd device to receive mouse and
> > keyboard events from Qemu. The advantage over USB is that vkbd
doesn''t
> > require frequent wakeups in Qemu.
> 
> Do we need an unplug protocol in order to stop these frequent wakeups?
No, we just need to disable USB. The only reason to have USB is to have
USB tablet support (absolute mouse coordinates).

> Do frontends/guests generally cope with two keyboards correctly?
> (whatever correctly means, I guess it''s not obvious once you have
a vfb
> as well as emulated VGA).
Yes, without any problems. Having multiple vfbs would be more
complicated but it is not part of this series.

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Stefano Stabellini

2011-Jun-27 13:20 UTC

head link

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

On Mon, 27 Jun 2011, Ian Campbell wrote:> On Mon, 2011-06-27 at 13:14 +0100, Stefano Stabellini wrote:
> > On Mon, 27 Jun 2011, Ian Campbell wrote:
> > > On Fri, 2011-06-24 at 17:29 +0100, Stefano Stabellini wrote:
> > > > PV on HVM drivers can connect to the vkbd device to receive
mouse and
> > > > keyboard events from Qemu. The advantage over USB is that
vkbd doesn''t
> > > > require frequent wakeups in Qemu.
> > > 
> > > Do we need an unplug protocol in order to stop these frequent
wakeups?
> > 
> > No, we just need to disable USB. The only reason to have USB is to
have
> > USB tablet support (absolute mouse coordinates).
> 
> That means users need to be aware that they have the appropriate
> frontends and manually edit their guest config?
Consider that usb is already off by default, users need to add usb=1 to
the config file in order to enable it.
Also even with usb=0 everything will keep working as expected, only the
"mouse experience" will be worse.

So I don''t see this as a particular problem either way, maybe we should
just add a note to the 4.2 xen release about the PV mouse and keyboard
protocol and why it is a good idea to disable usb.

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel

Xen devel - Jun 2011 - [PATCH] libxl: add a vkbd device to HVM guests by default

[Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default

Re: [Xen-devel] [PATCH] libxl: add a vkbd device to HVM guests by default