On Thu 09 Aug 2018 11:35:01 PM CEST, Max Reitz wrote: > If the backing file is overridden, this most probably does change the > guest-visible data of a BDS. Therefore, we will need to consider this > in bdrv_refresh_filename(). > > To see whether it has been overridden, we might want to compare > bs->backing_file and bs->backing->bs->filename. However, > bs->backing_file is changed by bdrv_set_backing_hd() (which is just used > to change the backing child at runtime, without modifying the image > header), so bs->backing_file most of the time simply contains a copy of > bs->backing->bs->filename anyway, so it is useless for such a > comparison.
What's the point of bs->backing_file then? In what cases is it different from backing->bs->filename? Berto
