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 0B5B5E73158 for ; Mon, 2 Feb 2026 11:11:18 +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:Content-Type:MIME-Version: References:In-Reply-To:Subject:Cc:To:From:Message-ID: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=5GaSxpL0c1F3l2pT2M34z9KbB0HtDXYwv2jEguO8oOA=; b=3S1hGlo6zSN8YYttIkHNLMK8Qj VH2y5ArfqPNgZtpr+YOI1jLyn8TxXPRvezOBv7vT8CmKf8+/8Zg9Ix1lqNORsjYgPiJ7Sr92Wj3u1 CYv3Eh6r73/fiZSvW8XEOo2UywHrgVpt7nqO1pbAYrMADq7Ge25lLumT8COGwYnH6n91E7Xhx+lqr QaxYZ3GgAbSU5fItPY1cdkZwkavypo6uGADCOTJhXUYEFNAWCl/GQvVNQOxn/RTf5Swym2Jy7jwHj gNq+ZtJkoGdyRoh0QymdDmCk0NiwrrjIHdG8rj4NWvBH+PuzJ+a8ht26DhQUQVy5OH6Z7TdNlHxDY sfDfZ9uQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vmrpo-00000004scY-2Qch; Mon, 02 Feb 2026 11:11:12 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vmrpl-00000004scA-39VK for linux-arm-kernel@lists.infradead.org; Mon, 02 Feb 2026 11:11:11 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id F0A8443DA7; Mon, 2 Feb 2026 11:11:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CA0EFC116C6; Mon, 2 Feb 2026 11:11:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770030668; bh=p759RUX5e3pnwmjWak5xYVtt1mYivnUA03Hiv54OSFQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=SPppoJVVbE+TBYd2ofa58Jo3oyAnysjG2V0tChex+m+fQYGGaNVBDUmuGRs0ccsFE fNqROvL7jJYe98XLNiyYsGWGcUytMjIU9jRFcHdpgkK79f8EGTBrjKlDdp0x/ztCIL dGQe4Nu4haxGZSJnrnQxhNAT191PnTKf6o7fuYPPgz3m/PQufWOTrzwPZAutaAtRbS h+WkwQ85Gz0fZDcn/eynGHUxZAUYR720BhoxLBM3M7KGsWNjJmk+iCiTImdLsnkNLW 8B2uxx49rUoQyuF3Z6+ZpoabSrxBn5+13xqsZFRMZIY+czSEplFYiDmm3h/fNqIOLl pP5bn1KA+1MdQ== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vmrpi-00000007kae-1kH1; Mon, 02 Feb 2026 11:11:06 +0000 Date: Mon, 02 Feb 2026 11:11:05 +0000 Message-ID: <86v7gf9z92.wl-maz@kernel.org> From: Marc Zyngier To: "Christian Marangi (Ansuel)" Cc: "Russell King (Oracle)" , Geert Uytterhoeven , Linus Walleij , Arnd Bergmann , Andrew Morton , Geert Uytterhoeven , "Kirill A. Shutemov" , Thomas Gleixner , Jonathan Corbet , "Mike Rapoport (IBM)" , Eric DeVolder , Nathan Chancellor , Kees Cook , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Bjorn Andersson , Konrad Dybcio , John Crispin Subject: Re: [PATCH v2 0/2] ARM: decompressor: support AUTO_ZRELADDR and appended DTB In-Reply-To: References: <20240121203009.9257-1-ansuelsmth@gmail.com> <65d62b60.050a0220.c7b96.614e@mx.google.com> <666ad6e0.df0a0220.f8b16.4a5e@mx.google.com> <666b2379.5d0a0220.c7eec.8b6f@mx.google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: ansuelsmth@gmail.com, linux@armlinux.org.uk, geert@linux-m68k.org, linus.walleij@linaro.org, arnd@arndb.de, akpm@linux-foundation.org, geert+renesas@glider.be, kirill.shutemov@linux.intel.com, tglx@linutronix.de, corbet@lwn.net, rppt@kernel.org, eric.devolder@oracle.com, nathan@kernel.org, keescook@chromium.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, andersson@kernel.org, konrad.dybcio@somainline.org, john@phrozen.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260202_031109_962909_6FA9EA05 X-CRM114-Status: GOOD ( 39.90 ) 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 On Mon, 02 Feb 2026 11:03:24 +0000, "Christian Marangi (Ansuel)" wrote: > > Il giorno lun 2 feb 2026 alle ore 11:58 Russell King (Oracle) > ha scritto: > > > > On Mon, Feb 02, 2026 at 11:26:49AM +0100, Geert Uytterhoeven wrote: > > > FTR, I did provide my Tested-by for the first patch in [1]. > > > I still have this series in my local tree, which I test regularly on > > > a variety of Renesas ARM32 platforms and on BeagleBone Black. > > > > > > In fact, I had completely forgotten about this series, to the point > > > that I bisected a failure in booting mainline on one of my boards > > > using my current .config to the absence of the first patch ;-) > > > Apparently during the past years, I had modified my .config to make it > > > more generic, and make better use of the DTB (incl. chosen/bootargs), > > > which has a dependency on the first patch... > > > > What I would like to know is why anyone is using appended DTBs in this > > day and age, when surely by now, Arm based boot loaders have realised > > that Arm moved to use device trees ages ago, and the kernel requires > > a DTB in addition to the kernel image itself. > > > > Appended DTB support was only there as a stop-gap for those boot > > loaders that were around before DTB support was added, and have no > > capability of dealing with a separate DTB. > > > > Come on. It's 2026. DTB has been supported on 32-bit ARM for fifteen > > years. Surely everyone's now got modern boot loaders. > > > > If not, it's time to say this: fix the boot loader. > > > > The main problem is that sometimes it's not possible to update the bootloader > at all. Either they never provided the source or Uboot is not even used. > > And on some device updating the bootloader is risky as you would end up > in a brick. (no way to recover it) > > Also other case usually sign the bootloader and permit to load whatever > image you want so also problematic to update the bootloader. > > Sadly for these device, it's full of corner situation where the Vendor used > a badly configured SDK and made a single bootloader on it. > > For example QCOM Uboot SDK still target ancient 2012 version if I'm not > wrong. If you can boot the kernel, you can also boot a secondary bootloader that will do the right thing by exposing a DT. Fixing the boot flow should be the priority, rather than adding more band-aids to the kernel. Thanks, M. -- Without deviation from the norm, progress is not possible.