From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1C473C43458 for ; Fri, 3 Jul 2026 15:52:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=3tFkhV9y3YSpG7ZFQq6X18e4oKX1Jy1S3KYwLSR0WpE=; b=fgZ+uIa6utVxSN9aXjCeesPYEx YOga8WT50PhkEjjBxVqs2Sing1ZVv2ogI9uziXyqzyjFfpHecaGQVtoJH3WPyazk0KiTilNAWewZX TZxnGmVSgKAA3x8WH88VSbmNKWXl7+sjh7aQeXKR4aejVAb0oyt3Tgqmzl3cJgyzmBV4Bm9ay6gdy 1AAfFT8j44pPhUT3NM5ieqcgC3mqb6MzBpjf6wudrCh7o9xiw9UCMozXDcSS042mwmDZUFMwGx8s+ /ia8m+6uTSgRA6NmOcFIhPHbXe0U9NcW+weaJmlfEnKLcIG9BA3xgb1YrqON5e9GxVQt/wPLrpk1f 5Se55bUA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wfgBE-00000007Rzd-173E; Fri, 03 Jul 2026 15:51:52 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wfgBC-00000007Ryr-3YCx for linux-arm-kernel@lists.infradead.org; Fri, 03 Jul 2026 15:51:50 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id EBB0960051; Fri, 3 Jul 2026 15:51:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 361A11F000E9; Fri, 3 Jul 2026 15:51:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783093909; bh=3tFkhV9y3YSpG7ZFQq6X18e4oKX1Jy1S3KYwLSR0WpE=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=S1W87LOQhTm4vC9qjjU6evSDA7cIZuPkpXGHrVl4l/Y2SBeuvoH3TBVUAYI6gg35B VMDwmFQDailxQp2+c++0GbmJHxuzaTy2XN9S6wp83hs4sHDycopFzFEGVwUjMObiUT Je63NveeqJD6Bam9yHz6UZ0bTDCVl+eHpKGJeEkLKBIr4CyfnngUwG0MCmPLcc6/4h yYOYIyfExN+aPu8V3GrcFy8GRZPzFJMaCxni28KSWA1qdJf88B3BNZpkckITHIPCoh KkZzB4kXLBDry3iqhIgrM+IQPgQdLa6f1pP+eq1R4oAkPxZVWlMrXwRqEHg1yYZr22 9/n+cUnD34acg== Date: Fri, 3 Jul 2026 16:51:43 +0100 From: Sudeep Holla To: Sneh Mankad Cc: Thomas Gleixner , Daniel Lezcano , Peter Zijlstra , "Rafael J. Wysocki" , Pavel Machek , Len Brown , Catalin Marinas , Mark Rutland , Lorenzo Pieralisi , Will Deacon , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2] arm64: Disallow disabling boot CPU based on config Message-ID: <20260703-competent-adaptable-coot-f8daaf@sudeepholla> References: <20260703-disable_boot_cpu_offline-v2-1-782d16ff58c3@oss.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260703-disable_boot_cpu_offline-v2-1-782d16ff58c3@oss.qualcomm.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org (It is always good to cc all PSCI maintainer for any ARM64 CPU hotpug/suspend related changes) On Fri, Jul 03, 2026 at 04:50:02PM +0530, Sneh Mankad wrote: > The Qualcomm SoCs like LeMans, Monaco support suspend to ram which leads > the SoC to ACPI S3 similar state where SoC is turned off and DDR is > retained. The hardware design on these SoCs forces a constraint to suspend > and resume the system on boot CPU / CPU0. > And you fail to explain why they have that constraint. Is it because some secure context is not allowed to migrate ? We already have a mechanism for that in place and this hack is not at all required. -- Regards, Sudeep