[libvirt] [PATCH 2/2] qemu: Allow seamless migration for domains with multiple graphics

[Jiri Denemark]

On Wed, Jul 03, 2013 at 12:10:23 +0100, Daniel Berrange wrote:
> On Tue, Jul 02, 2013 at 03:46:01PM +0200, Martin Kletzander wrote:
> > Since commit 23e8b5d8, the code is refactored in a way that supports
> > domains with multiple graphics elements and commit 37b415200 allows
> > starting such domains.  However none of those commits take migration
> > into account.  Even though qemu doesn't support relocation for
> > anything else than VNC and for no more than one graphics, there is no
> > reason to hardcode one graphics into this part of the code as well.
> 
> I think you mean  s/VNC/SPICE/ here.
> 
> > 
> > Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
> > ---
> >  src/qemu/qemu_migration.c | 29 ++++++++++++++++++-----------
> >  1 file changed, 18 insertions(+), 11 deletions(-)
> > 
> > diff --git a/src/qemu/qemu_migration.c b/src/qemu/qemu_migration.c
> > index 69d5398..d1a86b7 100644
> > --- a/src/qemu/qemu_migration.c
> > +++ b/src/qemu/qemu_migration.c
> > @@ -427,19 +427,21 @@ qemuMigrationCookieAddGraphics(qemuMigrationCookiePtr mig,
> >                                 virQEMUDriverPtr driver,
> >                                 virDomainObjPtr dom)
> >  {
> > +    size_t i = 0;
> > +
> >      if (mig->flags & QEMU_MIGRATION_COOKIE_GRAPHICS) {
> >          virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> >                         _("Migration graphics data already present"));
> >          return -1;
> >      }
> > 
> > -    if (dom->def->ngraphics == 1 &&
> > -        (dom->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_VNC ||
> > -         dom->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_SPICE)) {
> > -        if (!(mig->graphics =
> > -              qemuMigrationCookieGraphicsAlloc(driver, dom->def->graphics[0])))
> > -            return -1;
> > -        mig->flags |= QEMU_MIGRATION_COOKIE_GRAPHICS;
> > +    for (i = 0; i < dom->def->ngraphics; i++) {
> > +       if (dom->def->graphics[i]->type == VIR_DOMAIN_GRAPHICS_TYPE_SPICE) {
> > +           if (!(mig->graphics =
> > +                 qemuMigrationCookieGraphicsAlloc(driver, dom->def->graphics[i])))
> > +               return -1;
> > +           mig->flags |= QEMU_MIGRATION_COOKIE_GRAPHICS;
> > +       }
> >      }

I think you should break the loop inside the if statement to make it
clear qemuMigrationCookieGraphicsAlloc won't be called more than once
causing a memory leak.

Jirka