[PATCH v9 0/8] blk-mq: fix possible deadlocks

[Yu Kuai]

Fix deadlocks:
 - patch 1-2, pcpu_alloc_mutex under q_usage_counter in blk-wbt;
 - patch 3-8, debugfs_mutex under q_usage_counter;

Yu Kuai (8):
  blk-wbt: factor out a helper wbt_set_lat()
  blk-wbt: fix possible deadlock to nest pcpu_alloc_mutex under
    q_usage_counter
  blk-mq-debugfs: factor out a helper to register debugfs for all rq_qos
  blk-rq-qos: fix possible debugfs_mutex deadlock
  blk-mq-debugfs: make blk_mq_debugfs_register_rqos() static
  blk-mq-debugfs: remove blk_mq_debugfs_unregister_rqos()
  blk-mq-debugfs: add missing debugfs_mutex in
    blk_mq_debugfs_register_hctxs()
  blk-mq-debugfs: warn about possible deadlock

 block/blk-mq-debugfs.c |  68 ++++++++++++-------
 block/blk-mq-debugfs.h |   8 +--
 block/blk-rq-qos.c     |  11 ---
 block/blk-sysfs.c      |  39 +----------
 block/blk-wbt.c        | 149 ++++++++++++++++++++++++++++++-----------
 block/blk-wbt.h        |   7 +-
 6 files changed, 159 insertions(+), 123 deletions(-)

-- 
2.51.0