From: Jan Kara jack@suse.cz
stable inclusion from stable-v5.10.121 commit 70a7dea84639bcd029130e00e01792eb9207fb38 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60IHY CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit 09f871868080c33992cd6a9b72a5ca49582578fa upstream.
Track whether bfq_group is still online. We cannot rely on blkcg_gq->online because that gets cleared only after all policies are offlined and we need something that gets updated already under bfqd->lock when we are cleaning up our bfq_group to be able to guarantee that when we see online bfq_group, it will stay online while we are holding bfqd->lock lock.
CC: stable@vger.kernel.org Tested-by: "yukuai (C)" yukuai3@huawei.com Signed-off-by: Jan Kara jack@suse.cz Reviewed-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20220401102752.8599-7-jack@suse.cz Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Jason Yan yanaijie@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- block/bfq-cgroup.c | 3 ++- block/bfq-iosched.h | 2 ++ 2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c index abd01025d043..6846bfe03912 100644 --- a/block/bfq-cgroup.c +++ b/block/bfq-cgroup.c @@ -555,6 +555,7 @@ static void bfq_pd_init(struct blkg_policy_data *pd) */ bfqg->bfqd = bfqd; bfqg->active_entities = 0; + bfqg->online = true; bfqg->rq_pos_tree = RB_ROOT; }
@@ -601,7 +602,6 @@ struct bfq_group *bfq_find_set_group(struct bfq_data *bfqd, struct bfq_entity *entity;
bfqg = bfq_lookup_bfqg(bfqd, blkcg); - if (unlikely(!bfqg)) return NULL;
@@ -959,6 +959,7 @@ static void bfq_pd_offline(struct blkg_policy_data *pd)
put_async_queues: bfq_put_async_queues(bfqd, bfqg); + bfqg->online = false;
spin_unlock_irqrestore(&bfqd->lock, flags); /* diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h index fb51e5ce9400..b116ed48d27d 100644 --- a/block/bfq-iosched.h +++ b/block/bfq-iosched.h @@ -901,6 +901,8 @@ struct bfq_group {
/* reference counter (see comments in bfq_bic_update_cgroup) */ int ref; + /* Is bfq_group still online? */ + bool online;
struct bfq_entity entity; struct bfq_sched_data sched_data;