From: Tejun Heo tj@kernel.org
mainline inclusion from mainline-5.3-rc1 commit 71c814077de60b2e7415dac6f5c4e98f59d521fd category: feature bugzilla: 38688 CVE: NA
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When blkcg_activate_policy() is creating blkg_policy_data for existing blkgs, it did in the wrong order - descendants first. Fix it. None of the existing controllers seem affected by this.
Signed-off-by: Tejun Heo tj@kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk
Conflict: block/blk-cgroup.c Signed-off-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Hou Tao houtao1@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- block/blk-cgroup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index 8038c2b83f853..4a8151ecd8a66 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1445,7 +1445,8 @@ int blkcg_activate_policy(struct request_queue *q,
spin_lock_irq(q->queue_lock);
- list_for_each_entry(blkg, &q->blkg_list, q_node) { + /* blkg_list is pushed at the head, reverse walk to init parents first */ + list_for_each_entry_reverse(blkg, &q->blkg_list, q_node) { struct blkg_policy_data *pd;
if (blkg->pd[pol->plid])