Re: [PATCH] block, bfq: fix null pointer dereference in bfq_bio_bfqg()

[Yu Kuai]

Hi!

在 2022/11/08 20:48, Jan Kara 写道:
> Hum, that is indeed contrieved ;). Your fixup makes sense so feel free to
> add:
>
> Reviewed-by: Jan Kara <jack@xxxxxxx>

Thanks for the review, our test do many unusual operations together...

Thanks,
Kuai
> 								Honza
>
> > diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
> > index 144bca006463..7d624a3a3f0f 100644
> > --- a/block/bfq-cgroup.c
> > +++ b/block/bfq-cgroup.c
> > @@ -610,6 +610,10 @@ struct bfq_group *bfq_bio_bfqg(struct bfq_data *bfqd, struct bio *bio)
> >   	struct bfq_group *bfqg;
> >   
> >   	while (blkg) {
> > +		if (!blkg->online) {
> > +			blkg = blkg->parent;
> > +			continue;
> > +		}
> >   		bfqg = blkg_to_bfqg(blkg);
> >   		if (bfqg->online) {
> >   			bio_associate_blkg_from_css(bio, &blkg->blkcg->css);
> > --
> > 2.31.1