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Mon, 02 Feb 2026 07:21:33 -0800 (PST) From: Jens Axboe To: Yu Kuai Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Ming Lei , Nilay Shroff , Hannes Reinecke In-Reply-To: <20260202080523.3947504-1-yukuai@fnnas.com> References: <20260202080523.3947504-1-yukuai@fnnas.com> Subject: Re: [PATCH v9 0/8] blk-mq: fix possible deadlocks Message-Id: <177004569337.1085433.15214183568484883142.b4-ty@kernel.dk> Date: Mon, 02 Feb 2026 08:21:33 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Mailer: b4 0.14.3 On Mon, 02 Feb 2026 16:05:15 +0800, Yu Kuai wrote: > 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 > > [...] Applied, thanks! [1/8] blk-wbt: factor out a helper wbt_set_lat() commit: 2751b90051a0211ed7c78f26eb2a9b7038804b9b [2/8] blk-wbt: fix possible deadlock to nest pcpu_alloc_mutex under q_usage_counter commit: 41afaeeda5099d9cd07eaa7dc6c3d20c6f1dd9e9 [3/8] blk-mq-debugfs: factor out a helper to register debugfs for all rq_qos commit: 3f0bea9f3b9e7d9bdc3794103575168ef007d309 [4/8] blk-rq-qos: fix possible debugfs_mutex deadlock commit: 3c17a346ffc613615f48c6f1ed30cdf328bab805 [5/8] blk-mq-debugfs: make blk_mq_debugfs_register_rqos() static commit: 70bafa5e31ff979c4c38ac9838cc960a32c04f49 [6/8] blk-mq-debugfs: remove blk_mq_debugfs_unregister_rqos() commit: 5ae4b12ee6422a816efca4ede8411e4d5503b5ac [7/8] blk-mq-debugfs: add missing debugfs_mutex in blk_mq_debugfs_register_hctxs() commit: 9d20fd6ce1ba9733cd5ac96fcab32faa9fc404dd [8/8] blk-mq-debugfs: warn about possible deadlock commit: 65d466b6298470ce21ab21ebfdb51309d515737d Best regards, -- Jens Axboe