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Mon, 15 Sep 2025 12:06:10 -0700 (PDT) From: Jens Axboe To: Fengnan Chang , Sasha Levin , Diangang Li , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, Max Kellermann Cc: stable@vger.kernel.org In-Reply-To: <20250912000609.1429966-1-max.kellermann@ionos.com> References: <20250912000609.1429966-1-max.kellermann@ionos.com> Subject: Re: [PATCH] io_uring/io-wq: fix `max_workers` breakage and `nr_workers` underflow Message-Id: <175796316976.265356.16431775523856266594.b4-ty@kernel.dk> Date: Mon, 15 Sep 2025 13:06:09 -0600 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-dev-2ce6c On Fri, 12 Sep 2025 02:06:09 +0200, Max Kellermann wrote: > Commit 88e6c42e40de ("io_uring/io-wq: add check free worker before > create new worker") reused the variable `do_create` for something > else, abusing it for the free worker check. > > This caused the value to effectively always be `true` at the time > `nr_workers < max_workers` was checked, but it should really be > `false`. This means the `max_workers` setting was ignored, and worse: > if the limit had already been reached, incrementing `nr_workers` was > skipped even though another worker would be created. > > [...] Applied, thanks! [1/1] io_uring/io-wq: fix `max_workers` breakage and `nr_workers` underflow (no commit info) Best regards, -- Jens Axboe