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 X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9CB5C282E1 for ; Sat, 25 May 2019 00:22:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 999DD21851 for ; Sat, 25 May 2019 00:22:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="U3fzjaiN" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726262AbfEYAWt (ORCPT ); Fri, 24 May 2019 20:22:49 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:44204 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726166AbfEYAWt (ORCPT ); Fri, 24 May 2019 20:22:49 -0400 Received: by mail-pg1-f196.google.com with SMTP id n2so5867827pgp.11; Fri, 24 May 2019 17:22:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=7MZFVL6BQOoEldIxODirdsUOwMtCHcXwhPVYVkRjlWA=; b=U3fzjaiN70Tkffyo7D37fJ/8//S148cw2r1qtvNaX3GvGQ+gtdl4yOP0L7Yo8sy0D8 +C/xQyb/jdXwEx9FUve4BUfVoE/Goi3sMQ3fph8MFjahikqLvCb9oqAdinl1D5bINwFS /8nnjA9yq5x9HcXSH4reh7I2GSNiZfEL8sWTg3Ocf+BxeqqAq6TzUApx04xO6TxmgSk8 viTrnR7HLQw+L6VSaj+5gxoComeTXKD5YfngAL4H6GlURrrfOupGh9FZa7aP4Q15X3eh qmqQXyirjn3TPOOIOdO9RStQiDp/e9uu+1d/A+Fk45qZ9ISnSW1lwyvYdUc8UxWNBrIC WDmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=7MZFVL6BQOoEldIxODirdsUOwMtCHcXwhPVYVkRjlWA=; b=dVh9DH7BxxvQewvqUrTi4cFVgg9Q62JV57aAugLEOWsIi54nuzcUZM7Bo8iuVcndju A/T5bqIg9sseY+X4MxmqJ9Hbq4IsVsWTM5SoYlwIoWTAHNI4IQPLP17Qw0gdXVCDbrpI FBEpQWmuBnFOwuvbjHxBc3H+to+1gO1SF3A8xAvBXs/B/BV8Xy2Wlw5EDgYihdsheyw9 HExEpDcP1M1oULDedGbH1wGa7SZGBQBMOY5rI1audxnbECojluyupNsvjKVufg6ur1e0 Q4YimG+xgBgGUy04VJNuHv8ouQKnF2EzguuRokaMTqLFH+/snCimxxsSPd+tkhOYI448 2JoA== X-Gm-Message-State: APjAAAXePglFrDEbyHD1N9n7RKf8MIITzx3qUAQ5rNi6pqWkb9WXH42a DuPttujYC/Pus7RzCqI3NVnPSYkr X-Google-Smtp-Source: APXvYqyDNBrKpadgNtJa1k0AdKOxS6UC831LZTk4NOZNI9cSfDeSuhRNM1nbsMxhKNERdbGyg7ZmLA== X-Received: by 2002:a63:9a52:: with SMTP id e18mr6546603pgo.335.1558743768695; Fri, 24 May 2019 17:22:48 -0700 (PDT) Received: from [192.168.1.70] (c-24-6-192-50.hsd1.ca.comcast.net. [24.6.192.50]) by smtp.gmail.com with ESMTPSA id e184sm5689646pfa.169.2019.05.24.17.22.47 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 24 May 2019 17:22:48 -0700 (PDT) Subject: Re: [PATCH v1 0/5] Solve postboot supplier cleanup and optimize probe ordering To: Saravana Kannan Cc: Rob Herring , Mark Rutland , Greg Kroah-Hartman , "Rafael J. Wysocki" , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Android Kernel Team References: <20190524010117.225219-1-saravanak@google.com> <06b479e2-e8a0-b3e8-567c-7fa0f1c5bdf6@gmail.com> From: Frank Rowand Message-ID: <6d3995c1-e1e7-35ff-d091-501822c97ecd@gmail.com> Date: Fri, 24 May 2019 17:22:47 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/24/19 2:53 PM, Saravana Kannan wrote: > On Fri, May 24, 2019 at 10:49 AM Frank Rowand wrote: >> >> On 5/23/19 6:01 PM, Saravana Kannan wrote: < snip > >> Another flaw with this method is that existing device trees >> will be broken after the kernel is modified, because existing >> device trees do not have the depends-on property. This breaks >> the devicetree compatibility rules. > > This is 100% not true with the current implementation. I actually > tested this. This is fully backwards compatible. That's another reason > for adding depends-on and going by just what it says. The existing > bindings were never meant to describe only mandatory dependencies. So > using them as such is what would break backwards compatibility. Are you saying that an existing, already compiled, devicetree (an FDT) can be used to boot a new kernel that has implemented this patch set? The new kernel will boot with the existing FDT that does not have any depends-on properties? -Frank