Re: [PATCH] libxl: new parameters for upstream qemu's vga interfaces

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

On Thu, 10 Oct 2013, Fabio Fantoni wrote:
> Il 10/10/2013 11:32, Ian Campbell ha scritto:
> > On Thu, 2013-10-10 at 11:26 +0200, Fabio Fantoni wrote:
> > > Il 30/09/2013 12:12, Fabio Fantoni ha scritto:
> > > > Change the qemu parameters for upstream qemu vgas to the
> > > > new ones (-device), introduced some years ago.
> > > Ping
> > Please CC the qemu maintainers (Stefano & Anthony), although these
> > patches touch the toolstack they are logically qemu patches and need
> > their ack.
> 
> Thanks for your reply, I added Anthony on CC and Stefano was already on it.
> 
> > > > Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
> > > > ---
> > > >    tools/libxl/libxl_dm.c |   12 +++++-------
> > > >    1 file changed, 5 insertions(+), 7 deletions(-)
> > > > 
> > > > diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
> > > > index 43c3bec..2c6f5d9 100644
> > > > --- a/tools/libxl/libxl_dm.c
> > > > +++ b/tools/libxl/libxl_dm.c
> > > > @@ -486,15 +486,13 @@ static char **
> > > > libxl__build_device_model_args_new(libxl__gc *gc,
> > > >               switch (b_info->u.hvm.vga.kind) {
> > > >            case LIBXL_VGA_INTERFACE_TYPE_STD:
> > > > -            flexarray_vappend(dm_args, "-vga", "std", NULL);
> > > > +            flexarray_append_pair(dm_args, "-device", "VGA");
> > > >                break;
> > > >            case LIBXL_VGA_INTERFACE_TYPE_CIRRUS:
> > > > -            flexarray_vappend(dm_args, "-vga", "cirrus", NULL);
> > > > -            if (b_info->video_memkb) {
> > > > -                flexarray_vappend(dm_args, "-global",
> > > > -                    GCSPRINTF("vga.vram_size_mb=%d",
> > > > -                    libxl__sizekb_to_mb(b_info->video_memkb)), NULL);
> > > > -            }
> > > > +            flexarray_append_pair(dm_args, "-device", "cirrus-vga");
> > > > +            flexarray_append_pair(dm_args, "-global",
> > > > +                GCSPRINTF("vga.vram_size_mb=%d",
> > > > +                libxl__sizekb_to_mb(b_info->video_memkb)));
> > > >                break;
> > > >            }

Aside from switching to the new parameter format, this patch also
removes the

if (b_info->video_memkb) {

check before passing the -global paramter. Is it deliberate?
If so, it would be best to write down the motivation in the commit
message.
That said, the parameter change looks OK.