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Message-Id: <20250917213203.4608d54da45a5b8bc80c2004@linux-foundation.org> In-Reply-To: References: <20250917212959.355656-1-sunjunchao@bytedance.com> <20250917152155.5a8ddb3e4ff813289ea0b4c9@linux-foundation.org> <20250917202606.4fac2c6852abc5ba8894f8ee@linux-foundation.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: D7D5FC0003 X-Stat-Signature: 13g9uw4uktxno3octayykhwiz7w4jhut X-Rspam-User: X-HE-Tag: 1758169925-992143 X-HE-Meta: U2FsdGVkX19tGcgZXBW7CzLjcto63K2JvXf9bplgRVoN75cpEghEuaXa0Y3scvjIx2gVCLY2/UWANnj4tzhHv8h6jzVlHCO41GdOjhi5Cd/1L6AJ+hstGxv/rBx4lp4kuC+8DRmv34FA4X+ba7zeg07bgn6iiXRh583E2IeN7DQDUcfilIgaBikNsk4SSyrmFR/DQnXd2ebv5fS75EhehpFc1AFXysFRva2ViqC215R7lRY5gRX6m9k18yvTf+SjxXb+T8+SXPvs7JreVTsTPuEiwxdf4P//zlGBhse06oFEAOMDPZhTLcQYgH/ACZGpW6jc/Uc1ehoK5qeSp61dGsLVmaq7vb4xBQ8p4Qtm3AwEIltgPrbTujh5jUu49yb9Yi8Cy9dP7R4/BfwZhubb9wUpX4XYViLdlvQibQpZUt2Tdg0d+TocNKfeWQiVbPTGjf9EYu7uXYfo03GtyXDGMom0yJtPo4KObPs97jjDvoe4en0Vl7azHRJEoVz/eRs97/hBBVAvosSlj8+E5OKPflOzXV8HvH4uVJRO6FOkoY3/A7vRQi0lf6wo89j3tTyVTTQrvMJRj0vld+Dm65HU88UFp5wo9miY+pinU3BdOFNhzfKOQJo8NuUB/YrCrn/0E5xwsQhgnD9RNRM6AkHs0CQBFrpFMOmWf1WBQrUNYNhtaSPtZ7Fh7d/0F84q0VGQbSSu93l8K3zOzYuNXhxgdVq0bd/kAOc3YHvM2lSH/9qznarfjKKPMhKe+HETuJ1860MQu1Q6sICKOBIUvKSnlftGKAKBFanPGeDJXkONDgA99Q6aj5n9j/anmxVENZ3/kHXfcRITE14Gw1mXbYYNeOehqXO4fNA4yHcenbK8mZb9upHJwFqDKYTi1QbEQGQh++WF9tAD0VM97dk8S3LTFG9cDAIeBXt7wEcpxUfJeGaHdSMJemOZ5ywrOXjMHznu4GPsCp6MDBLVx1MmgSh 1MjAAOQI 1gP0GnLKoZt8EjGpmlQ2Ex2W+n14jBjmInYRiFnC4KlBbItIWhLm9AB1xHmfiGWexFyaQh04v4WOK82Zdoyug+glEjNh37oBljFSfeyS8UU6KidqTYOCYOWxKQVrjkgmQiJUcgKTHBJMNT6kFszAuzUZOYS/DlLBwPFo880ie6x3pYZymyNIPUxpICtmQtOehG3gDI17SeTUyeV6iBb7rgEiZagLwUItyU6SO9qSl18q1TaSc0bPUFzysBcbIGEaL50ZLqJvy8tVGc/L2DoexaKdyxzrYVsvHivx8G7Uraowb/f0= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, 18 Sep 2025 12:22:35 +0800 Julian Sun wrote: > > Seems the intent here is mainly to prevent the warning. If that > > warning wasn't coming out, would we bother making these changes? If > > no, just kill the warning. > > Got it. Seems like there's no more impact other than the pesky warning. > BTW, I'm also seeing many hung task warnings when the mount/umount > syscall is waiting for the s_umount semaphore—while s_umount is held > by the writeback code path. I think the hung task is also undesirable, > right? Since AFAICS there's also no more impact instead of the pesky > warnings. Sure. Writeback is famous for potentially taking vast amounts of time and that's perfectly reasonable and expected - lots of dirty data takes lots of time to write out. There is no misbehavior in this and warning the operator about it is just silly. If there is no action either they or we can take to prevent the warning then just squash the warning.