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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3CB07C433F5 for ; Fri, 1 Oct 2021 12:01:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2952C61A6F for ; Fri, 1 Oct 2021 12:01:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354231AbhJAMCw (ORCPT ); Fri, 1 Oct 2021 08:02:52 -0400 Received: from mout.kundenserver.de ([212.227.17.24]:46239 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231321AbhJAMCu (ORCPT ); Fri, 1 Oct 2021 08:02:50 -0400 Received: from mail-wr1-f50.google.com ([209.85.221.50]) by mrelayeu.kundenserver.de (mreue107 [213.165.67.113]) with ESMTPSA (Nemesis) id 1N6c0W-1msZ7H0NNG-0180nj; Fri, 01 Oct 2021 14:01:05 +0200 Received: by mail-wr1-f50.google.com with SMTP id v25so4479815wra.2; Fri, 01 Oct 2021 05:01:04 -0700 (PDT) X-Gm-Message-State: AOAM533ioC2e3WWC+NmDbLYA5DUzZjwMKgsxKwfRAGzzx0iCCpsfAaB8 IrM+0oWGWECP8XyL72ngiVXnPDedjeofOp1WiWs= X-Google-Smtp-Source: ABdhPJxF7qwzgMOFRomdZPfIPBjV2u63kV0wQz6BuSjHgJ/rhb/kjnzII6TF6JxnJJ0KLkUW4F1MOePcz4q52bkqPzc= X-Received: by 2002:adf:a505:: with SMTP id i5mr638099wrb.428.1633089664533; Fri, 01 Oct 2021 05:01:04 -0700 (PDT) MIME-Version: 1.0 References: <20210928235635.1348330-1-willmcvicker@google.com> <7766faf8-2dd1-6525-3b9a-8ba790c29cff@canonical.com> In-Reply-To: From: Arnd Bergmann Date: Fri, 1 Oct 2021 14:00:47 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 00/12] arm64: Kconfig: Update ARCH_EXYNOS select configs To: Saravana Kannan Cc: Olof Johansson , Will McVicker , Krzysztof Kozlowski , Russell King , Catalin Marinas , Will Deacon , Michael Turquette , Stephen Boyd , Sylwester Nawrocki , Tomasz Figa , Chanwoo Choi , Linus Walleij , Alessandro Zummo , Alexandre Belloni , John Stultz , Thomas Gleixner , Lee Jones , Geert Uytterhoeven , "Cc: Android Kernel" , Linux ARM , Linux Kernel Mailing List , linux-samsung-soc , linux-clk , "open list:GPIO SUBSYSTEM" , linux-rtc@vger.kernel.org, Arnd Bergmann Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:foxnByHIMO41LZr2Z9LmJI+Xn9wMZxV+n7u/copOM8vplzqsmPq jR0qYunbX8ndaxF6fiJEnYKZ9QTe5YOqMK0OUEoCvLlMygoU7UBRCW3ZFeJV69c0fQhGMyU KdyNuOQRzyq+2oUnJVvEtvJRkHCMggf+sChlcywy2b/+o7SuV/BTtxlZK6sB41ilXcbhMoe Dmr6Rw9ls3MUfGuGRRjoA== X-UI-Out-Filterresults: notjunk:1;V03:K0:+EeM5I3yKm4=:BAfcGYStGatexgBFCaTvFU oiQpdFuvN4v0TRZjsV+YhZZotQduvRA0vDXaUAQTJcs9OlonWzFb0S0LVMGiKh1dXOywRnEtx DuwokwP5UM3PhQ5uoTIgx3ipQhpEthQ7Eit7Oz4/VO25jmDYxzVXdA3X5XWABXmU+m+soE1De Co1EBCoSavOaKaCKdLvHLnfitOsNwM/nPU/y8O98i4+gECri0B4LXN7dowu0U+vpYiVgU8hB4 enUhTY1su97SP6ItKlUAPAHgG/piBQA4dzmdX5aJz4vj4Wr15LLZ4JTriyXGPfA6Sf3nTn6CJ GTVt3ML9VUI6wBswEC8wT0KhjhO81hlNi8vdt/fQuIeRWoeSumTCdTc/6GCeBZSybDCVigFqw miUo4/6mdWnh5B4lRApFzNXAqdl8otP7n1kI+4uECuWym/Mr8qiM6ecM3b175YMw4m/GHN7dW LKJ9HSlGnnjGSAlRpX+iSP1UAnJJ8EwpjYhQh1xp418H10ujJUUG3CFFF+4pycXvVUKEEw6x9 oaMmLdWOhAYygO11OrqqkDZy1WR2nHaTQmAqOPRcOQQyQPVtUmTmDh3m3hVy8lfb2PndJvEgQ ul5kxDkaYPQHRTuz+cj52ZuR2uece/3paDTMAwnmMa83ePMDs4uAPZhwA2kSNMshq+ZU2c+vX 8wQGTi2UHweGAQ1dllSA07lqMGiy80hAfswcbqoBMSIUoQS1Dh2/tQ3Gsrh/d8ft6MQZ7QtSv 5cfuBFRnEXHeZRtQQr3feYQT7emRtFUmk053Vd6Y6giirKVOlnRVHOylSdean2esrUCYenSpK XqnNaRPLkdgUUTbOsqZLxViDsV9CzgCZmSqddDiIv70VI+bzMU7Nr0zHIjPuTB5oa/oso1yNZ K5kMYC3dRwa3WdnnViSg== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 1, 2021 at 8:02 AM Saravana Kannan wrote: > > A much more valuable approach would be to work towards being able to > > free up memory by un-probed drivers at the end of boot. That would > > possibly benefit all platforms on all architectures. > > Sure it would help memory after boot, but it won't help with size on > "disk", kernel load time, etc. And some of the devices have very tight > boot requirements. Think battery operated outdoor cameras for example. I think we can draw a clear line (or several lines) between devices that boot from strictly constrained NOR flash and those that run a platform-independent kernel. Also, when I look at a distro kernel, I see over 5000 kernel modules that need to be stored on disk, but only a small fraction of those are platform specific while most are for general-purpose pluggable devices, network features or file systems that could be used on any system. The vmlinux file is clearly too big and includes too much stuff that should be in loadable modules, but I'm not really that worried about disk space for the platform specific code. Arnd