Merge tag 'for-5.13/block-2021-04-27' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Pretty quiet round this time, which is nice. In detail:

   - Series revamping bounce buffer support (Christoph)

   - Dead code removal (Christoph, Bart)

   - Partition iteration revamp, now using xarray (Christoph)

   - Passthrough request scheduler improvements (Lin)

   - Series of BFQ improvements (Paolo)

   - Fix ioprio task iteration (Peter)

   - Various little tweaks and fixes (Tejun, Saravanan, Bhaskar, Max,
     Nikolay)"

* tag 'for-5.13/block-2021-04-27' of git://git.kernel.dk/linux-block: (41 commits)
  blk-iocost: don't ignore vrate_min on QD contention
  blk-mq: Fix spurious debugfs directory creation during initialization
  bfq/mq-deadline: remove redundant check for passthrough request
  blk-mq: bypass IO scheduler's limit_depth for passthrough request
  block: Remove an obsolete comment from sg_io()
  block: move bio_list_copy_data to pktcdvd
  block: remove zero_fill_bio_iter
  block: add queue_to_disk() to get gendisk from request_queue
  block: remove an incorrect check from blk_rq_append_bio
  block: initialize ret in bdev_disk_changed
  block: Fix sys_ioprio_set(.which=IOPRIO_WHO_PGRP) task iteration
  block: remove disk_part_iter
  block: simplify diskstats_show
  block: simplify show_partition
  block: simplify printk_all_partitions
  block: simplify partition_overlaps
  block: simplify partition removal
  block: take bd_mutex around delete_partitions in del_gendisk
  block: refactor blk_drop_partitions
  block: move more syncing and invalidation to delete_partition
  ...

1 files changed, 8 insertions, 0 deletions

diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 271f6596435b..2a75bc7401df 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -972,6 +972,14 @@ void blk_mq_debugfs_register_sched_hctx(struct request_queue *q,
 {
 	struct elevator_type *e = q->elevator->type;
 
+	/*
+	 * If the parent debugfs directory has not been created yet, return;
+	 * We will be called again later on with appropriate parent debugfs
+	 * directory from blk_register_queue()
+	 */
+	if (!hctx->debugfs_dir)
+		return;
+
 	if (!e->hctx_debugfs_attrs)
 		return;