Quoting Cornelia Huck (2018-05-15 03:09:49)
> On Tue, 15 May 2018 09:18:52 +0200
> Thomas Huth <th...@redhat.com> wrote:
>
> > On 15.05.2018 08:31, Olaf Hering wrote:
> > > Currently the minimal supported version of glib is 2.22.
> > > Since testing is done with a glib that claims to be 2.22, but in fact
> > > has APIs from newer version of glib, this bug was not caught during
> > > submit of the patch referenced below.
> > >
> > > Replace g_realloc_n, which is available only since 2.24, with g_renew.
> > >
> > > Fixes commit 418026ca43 ("util: Introduce vfio helpers")
> > >
> > > Signed-off-by: Olaf Hering <o...@aepfle.de>
> > > ---
> > > This must go into stable-2.12.
> >
> > In that case please CC: qemu-sta...@nongnu.org (done now).
> >
> > Reviewed-by: Thomas Huth <th...@redhat.com>
> >
> > > util/vfio-helpers.c | 6 ++----
> > > 1 file changed, 2 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
> > > index 006674c916..1d9272efa4 100644
> > > --- a/util/vfio-helpers.c
> > > +++ b/util/vfio-helpers.c
> > > @@ -522,8 +522,7 @@ static IOVAMapping
> > > *qemu_vfio_add_mapping(QEMUVFIOState *s,
> > >
> > > assert(index >= 0);
> > > s->nr_mappings++;
> > > - s->mappings = g_realloc_n(s->mappings, sizeof(s->mappings[0]),
> > > - s->nr_mappings);
> > > + s->mappings = g_renew(IOVAMapping, s->mappings, s->nr_mappings);
> > > insert = &s->mappings[index];
> > > shift = s->nr_mappings - index - 1;
> > > if (shift) {
> > > @@ -577,8 +576,7 @@ static void qemu_vfio_undo_mapping(QEMUVFIOState *s,
> > > IOVAMapping *mapping,
> > > memmove(mapping, &s->mappings[index + 1],
> > > sizeof(s->mappings[0]) * (s->nr_mappings - index - 1));
> > > s->nr_mappings--;
> > > - s->mappings = g_realloc_n(s->mappings, sizeof(s->mappings[0]),
> > > - s->nr_mappings);
> > > + s->mappings = g_renew(IOVAMapping, s->mappings, s->nr_mappings);
> > > }
> > >
> > > /* Check if the mapping list is (ascending) ordered. */
> > >
>
> This looks fine to me, so
>
> Reviewed-by: Cornelia Huck <coh...@redhat.com>
>
> But this leads to another question: What do we do if we want a fix only
> in stable? Hypothetical scenario: Same parameters as for this patch
> (glib version bump, newer function sneaked in), but the older function
> that could be used in stable is clearly worse (IOW, we don't want it in
> the new version). Do we have a process to get a change only into stable?
>
I've answered in the form of a patch :)
"docs: add details regarding submitting stable-specific patches"
but here's a recent example:
https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg04999.html
