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cv=none; t=1794494464; b=7SlVU6N6a0sKIRCOO6S4+h3wGjsFZY0R1eqnCQ6wDJpq5fpjgJV295F7cSFMsUY0moekZT OkUj2wGivpHmS9FgFu4NX+vbjeCWZswLcK5JK2t9kVpcGo6NLCeGuRYGM1vwM+Xdbt2boR EGyYfQYuloiExJaba8YLzzWsN28G54Q= Received: from omf11.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 61E59A0600; Thu, 12 Nov 2026 14:41:03 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf11.hostedemail.com (Postfix) with ESMTPA id 7486120029; Thu, 12 Nov 2026 14:41:00 +0000 (UTC) Date: Thu, 12 Nov 2026 09:40:59 -0500 From: Steven Rostedt To: Peter Zijlstra Cc: Huacai Chen , Huacai Chen , Andrew Morton , Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Tiezhu Yang Subject: Re: [PATCH] lib/smp_processor_id: Don't warn if there is only one CPU Message-ID: <20261112094059.18f66c2a@fedora> In-Reply-To: <20261112081348.GB2668804@noisy.programming.kicks-ass.net> References: <20261111092421.3771992-1-chenhuacai@loongson.cn> <20261111170600.GS1779021@noisy.programming.kicks-ass.net> <20261112081348.GB2668804@noisy.programming.kicks-ass.net> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; 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Notably, there is no > requirement that the CPU bitmap is dense. You can have nr_cpu_ids at 256 > and use 255 for your boot CPU. It would be completely daft to do so, but > it is still valid. Hmm, I was under the impression that there would always be a CPU 0. Is it possible to boot with a non zero CPU setup? -- Steve