blkcg: use blkg_free() in blkcg_init_queue() failure path
When blkcg_init_queue() fails midway after creating a new blkg, it
performs kfree() directly; however, this doesn't free the policy data
areas. Make it use blkg_free() instead. In turn, blkg_free() is
updated to handle root request_list special case.
While this fixes a possible memory leak, it's on an unlikely failure
path of an already cold path and the size leaked per occurrence is
miniscule too. I don't think it needs to be tagged for -stable.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 1db904f..cd25183 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -70,7 +70,8 @@
for (i = 0; i < BLKCG_MAX_POLS; i++)
kfree(blkg->pd[i]);
- blk_exit_rl(&blkg->rl);
+ if (blkg->blkcg != &blkcg_root)
+ blk_exit_rl(&blkg->rl);
kfree(blkg);
}
@@ -938,7 +939,7 @@
radix_tree_preload_end();
if (IS_ERR(blkg)) {
- kfree(new_blkg);
+ blkg_free(new_blkg);
return PTR_ERR(blkg);
}