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charset=us-ascii Content-Disposition: inline In-Reply-To: <20261112094059.18f66c2a@fedora> X-Stat-Signature: nzuyk43hidu7y6hxw9p9zsu46fx8yi8o X-Rspamd-Queue-Id: 50CC1180007 X-Rspam-User: X-Rspamd-Server: rspam08 X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_PASS,SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-HE-Tag: 1794496074-933821 X-HE-Meta: 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 rAMLejHU Ke9ADsj936E6RZsjMDdUviY7MZcMYzafshDYtVMtiFr//r7WdlB79Dli7siPTFwqFrLxPbPUnWS3zk+y4MANjsQDRbgdtBtYPeYCxCbmvLsjrmIhDRfge9C/Hw9C9Jos/SB3nVo1PCtOMWFly2fEAqE9L1aJBNorGgcI2OLOJkBM+L1Q7PH3pi5SoLRQz0yn3wyFpf0TDBdEV1akJn3k99LzZa/R2G/yT7uNJ/Vm+uxBxEdCO51Ynm0M5KGvxUu1/X2qrGEcjG2l8RUt0tqh5x3IE/4zI2Gf8zqM3BUbpsiPxDI9X0T7V/t50+A== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Thu, Nov 12, 2026 at 09:40:59AM -0500, Steven Rostedt wrote: > On Thu, 12 Nov 2026 09:13:48 +0100 > Peter Zijlstra wrote: > > > num_possible_cpus() is what I was thinking of. 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? Yes. Voyager did that -- although that code is now long gone. In general we must not assume boot cpu is 0 -- although I don't know of any architecture that currently doesn't have that. Might be fun to have it as a debug option to catch out assumptions.