On Mon, 20 May 2013, Oskar Andero wrote: > Add a BUG_ON to catch any illegal value from the shrinkers. This fixes a > potential bug if scan_objects returns a negative other than -1, which > would lead to undefined behaviour. > > Cc: Glauber Costa <glom...@openvz.org> > Cc: Dave Chinner <dchin...@redhat.com> > Cc: Andrew Morton <a...@linux-foundation.org> > Cc: Hugh Dickins <hu...@google.com> > Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org> > Signed-off-by: Oskar Andero <oskar.and...@sonymobile.com> > --- > mm/vmscan.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 6bac41e..fbe6742 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -293,6 +293,7 @@ shrink_slab_one(struct shrinker *shrinker, struct > shrink_control *shrinkctl, > ret = shrinker->scan_objects(shrinker, shrinkctl); > if (ret == -1) > break; > + BUG_ON(ret < -1); > freed += ret; > > count_vm_events(SLABS_SCANNED, nr_to_scan);
Nack, this doesn't fix anything. I can see the intention, and for that it might make sense to turn this into VM_BUG_ON() so that anybody debugging an issue related to this with CONFIG_DEBUG_VM would get the indication, but I don't think we need to enforce the API with BUG_ON(). -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
