From: Zijun Hu quic_zijuhu@quicinc.com
blkcg_fill_root_iostats() iterates over @block_class's devices by class_dev_iter_(init|next)(), but does not end iterating with class_dev_iter_exit(), so causes the class's subsystem refcount leakage.
Fix by ending the iterating with class_dev_iter_exit().
Fixes: ef45fe470e1e ("blk-cgroup: show global disk stats in root cgroup io.stat") Reviewed-by: Michal Koutný mkoutny@suse.com Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: stable@vger.kernel.org Acked-by: Tejun Heo tj@kernel.org Signed-off-by: Zijun Hu quic_zijuhu@quicinc.com --- block/blk-cgroup.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index e68c725cf8d975f53703ecf6e6c50594076204c8..fb9858efdfe9443704cb9a239def0e08addf2518 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1138,6 +1138,7 @@ static void blkcg_fill_root_iostats(void) blkg_iostat_set(&blkg->iostat.cur, &tmp); u64_stats_update_end_irqrestore(&blkg->iostat.sync, flags); } + class_dev_iter_exit(&iter); }
static void blkcg_print_one_stat(struct blkcg_gq *blkg, struct seq_file *s)