From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Sat, 11 Mar 2023 10:34:39 +0100
Subject: [PATCH] Revert "blk-cgroup: dropping parent refcount after
 pd_free_fn() is done"
References: bsc#1012628
Patch-mainline: 6.2.4
Git-commit: c7241babf0855d8a6180cd1743ff0ec34de40b4e

This reverts commit 57a425badc05c2e87e9f25713e5c3c0298e4202c which is
commit c7241babf0855d8a6180cd1743ff0ec34de40b4e upstream.

It is reported to cause problems, as only 2 of the 3 patch series were
applied to the stable branches.

Reported-by: Mike Cloaked <mike.cloaked@gmail.com>
Reported-by: Eric Biggers <ebiggers@kernel.org>
Cc: Yu Kuai <yukuai3@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Sasha Levin <sashal@kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217174
Link: https://lore.kernel.org/r/ZAuPkCn49urWBN5P@sol.localdomain
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 block/blk-cgroup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index aa890e3e..9ac1efb0 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -124,8 +124,6 @@ static void blkg_free_workfn(struct work_struct *work)
 		if (blkg->pd[i])
 			blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
 
-	if (blkg->parent)
-		blkg_put(blkg->parent);
 	if (blkg->q)
 		blk_put_queue(blkg->q);
 	free_percpu(blkg->iostat_cpu);
@@ -160,6 +158,8 @@ static void __blkg_release(struct rcu_head *rcu)
 
 	/* release the blkcg and parent blkg refs this blkg has been holding */
 	css_put(&blkg->blkcg->css);
+	if (blkg->parent)
+		blkg_put(blkg->parent);
 	blkg_free(blkg);
 }
 
-- 
2.35.3