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[144.49.247.120]) by smtp-relay.gmail.com with ESMTPS id 98e67ed59e1d1-3adde20c410sm487560a91.3.2026.10.23.10.12.28 for (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 23 Oct 2026 10:12:29 -0700 (PDT) X-Relaying-Domain: broadcom.com X-CFilter-Loop: Reflected Received: by mail-ua1-f70.google.com with SMTP id a1e0cc1a2514c-99082f450bfso962051241.2 for ; Fri, 23 Oct 2026 10:12:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; t=1792775548; x=1793380348; darn=lists.infradead.org; h=content-transfer-encoding:content-type:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to :content-type; bh=vQ88d76TUq4k99QsUORpvk5GOBTjh2+OybJMDVnHW0U=; b=aXIrH1zDuaS3JqhJH4+febDXbwgEobOKJ08EhOhCGHSskEm2g2iZ0NmXvmCdlayPll NB6UJC/lvvMk3LKUDsRJxFiwQrM6jSVEY+1PijlHEE9pmLAgFmPf4QWoiQLaHmHmPo/Q oFafoYuzyxlKlOG7guQ+3n40mabDufcqmi7As= X-Forwarded-Encrypted: i=1; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-DetectorID-Processed: b00c1d49-9d2e-4205-b15f-d015386d3d5e X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261023_101230_690408_1AB233CB X-CRM114-Status: GOOD ( 12.44 ) X-Spam-Score: -2.4 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-7.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 10/19/26 06:08, Frederic Weisbecker wrote: > Between CPUHP_TEARDOWN_CPU and CPUHP_AP_OFFLINE, stop_machine executes > all the teardown callbacks while stopping all CPUs in the system. This > doesn't mix-up well with running RT or isolated tasks. > > In order to transition smoothly from global stop_machine to finer > grained synchronization between teardown callbacks and the other CPUs, > a new stop machine post function has been introduced to be executed > after the main one with IRQs still disabled while other CPUs can exit > stop_machine(). > > It *looks ok* to disable the cache readahead globally while the other > CPUs are running. Yes I think it is safe given that b15_rac_dying_cpu() will run on the dying CPU and any CPU that is left will basically re-enable the RAC afterwards if necessary in b15_rac_dead_cpu(). The hardware to test this is quite ancient, but if you give me a test case to exercise, I can give it a spin. Thank you Frederic! -- Florian