From: weiping zhang <zhangweiping@didichuxing.com>
Date: Tue, 10 Oct 2017 22:53:46 +0800
Subject: [PATCH] blkcg: check pol->cpd_free_fn before free cpd
Git-commit: 58a9edce0aa912640abe47d3fc039e6230ef848b
Patch-mainline: v4.15-rc1
References: bsc#1104967,FATE#325924

check pol->cpd_free_fn() instead of pol->cpd_alloc_fn() when free cpd.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: weiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Hannes Reinecke <hare@suse.com>
---
 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 d3f56baee936..e7ec676043b1 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1452,7 +1452,7 @@ int blkcg_policy_register(struct blkcg_policy *pol)
 	return 0;
 
 err_free_cpds:
-	if (pol->cpd_alloc_fn) {
+	if (pol->cpd_free_fn) {
 		list_for_each_entry(blkcg, &all_blkcgs, all_blkcgs_node) {
 			if (blkcg->cpd[pol->plid]) {
 				pol->cpd_free_fn(blkcg->cpd[pol->plid]);
@@ -1492,7 +1492,7 @@ void blkcg_policy_unregister(struct blkcg_policy *pol)
 	/* remove cpds and unregister */
 	mutex_lock(&blkcg_pol_mutex);
 
-	if (pol->cpd_alloc_fn) {
+	if (pol->cpd_free_fn) {
 		list_for_each_entry(blkcg, &all_blkcgs, all_blkcgs_node) {
 			if (blkcg->cpd[pol->plid]) {
 				pol->cpd_free_fn(blkcg->cpd[pol->plid]);
-- 
2.16.4