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McKenney" , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, rcu@vger.kernel.org, linux-doc@vger.kernel.org, John Ogness , Jonathan Corbet , Shuah Khan , Randy Dunlap , Ingo Molnar , Peter Zijlstra , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , K Prateek Nayak , luca abeni , Yuri Andriaccio , Yuri Andriaccio , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Boqun Feng , Uladzislau Rezki , Mathieu Desnoyers , Lai Jiangshan , Zqiang , Davidlohr Bueso , Tejun Heo , Johannes Weiner , Michal =?utf-8?Q?Koutn=C3=BD?= , Qais Yousef Subject: Re: [PATCH v2 0/7] sched: RT throttling cleanup and a bit of documentation Message-ID: <20261112152446.r1FzXVCR@linutronix.de> References: <20261110-sched_dl-v2-0-cc9399f7aeb1@linutronix.de> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On 2026-11-12 16:01:06 [+0100], Juri Lelli wrote: > Hello, Hi, > I wonder if this fixes is > > https://lore.kernel.org/lkml/20261108185406.1549770-6-mathieu.desnoyers@efficios.com/ Looks like it. I delayed the update to the thread which runs on the CPU and replaced the cpu_online() check with cpu_active(). It still aborts if it is not up. The other alternative is to skip sched_init_dl_servers() with RCU_TORTURE built-in. Side note: If you boot a 4 CPU system with maxcpus=2 then CPU 2+3 is offline. You can online them manually. sched_init_dl_servers() will not initialise them. > Thanks, > Juri Sebastian