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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 E485EC432BE for ; Wed, 25 Aug 2021 22:06:20 +0000 (UTC) Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E57DA61056 for ; Wed, 25 Aug 2021 22:06:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E57DA61056 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=konsulko.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.denx.de Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id 0746D81EBD; Thu, 26 Aug 2021 00:06:17 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=none (p=none dis=none) header.from=konsulko.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Authentication-Results: phobos.denx.de; dkim=pass (1024-bit key; unprotected) header.d=konsulko.com header.i=@konsulko.com header.b="QoU5OzFK"; dkim-atps=neutral Received: by phobos.denx.de (Postfix, from userid 109) id 6953D81F7B; Thu, 26 Aug 2021 00:06:15 +0200 (CEST) Received: from mail-qt1-x82f.google.com (mail-qt1-x82f.google.com [IPv6:2607:f8b0:4864:20::82f]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits)) (No client certificate requested) by phobos.denx.de (Postfix) with ESMTPS id 363BC80ECC for ; Thu, 26 Aug 2021 00:06:10 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=none (p=none dis=none) header.from=konsulko.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=trini@konsulko.com Received: by mail-qt1-x82f.google.com with SMTP id b1so812762qtx.0 for ; Wed, 25 Aug 2021 15:06:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=konsulko.com; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=/RflMYpJdo+ia1sOWFzuw/4RPNa9QGqTo+Sa9wLSkmE=; b=QoU5OzFKjbyggdbOYsCyM0wITQr2ZqU3W9QX7EmuSn2+p9tPkS/onw7zifzWmCFXOm 3fgLI0kWrtm8siVvp4u2Ox/uRQk3SWI7jqB22kXcSsMHx9ssjctSO5QBhMYoHTDnhYyY P9NppQ1S1JukyGm/HdmiJz53M8lBidkyJZY0g= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=/RflMYpJdo+ia1sOWFzuw/4RPNa9QGqTo+Sa9wLSkmE=; b=c0hVv20sX6IU4x5DuNWaXhB2O2ORAho0E/uTuugkDd3mZdCwipbl6LgFn4ruQbRfOt b9tKZKyQPTGmZBDdNsAEQPfZJhu4upsFF3vCh3/ncOd5Gw/k7wtf3ODSlzzi19dZe+A0 02MgpSEmkO6ylLEK2YuPUaGS97PXfjTubbhZ1otmWfnHhewQGUYCnI+DZGDeGMRfe9AI IUnZRiugVT86B0NJhlsKzqaEhaAePmpMfDRTPc3eUXGN/Hni9ZxfCUtbXGK+C6HkTRnE I7Y1nKF/u7SnkncFjFT2NXp4npyKaRegIXMKWDeeXz92dSR2mYMCqo/7lc9gAs/cF1Vn gqvg== X-Gm-Message-State: AOAM532fYtSdGk+dSkOhO4BlaB0xyoEUIYWG7+/TK40CoZRcZda1h9hp s7Lt40gPqILtahmCOacvq8Gf/w== X-Google-Smtp-Source: ABdhPJzdXso3HVu++z8Qq4KIgahfbUs8IvG078vrrW3zYkwvH8zh2mQWDmOsyCSHoRevRqnbG2lh3w== X-Received: by 2002:ac8:5a51:: with SMTP id o17mr454667qta.386.1629929168842; Wed, 25 Aug 2021 15:06:08 -0700 (PDT) Received: from bill-the-cat (2603-6081-7b01-cbda-519a-4843-2801-9790.res6.spectrum.com. [2603:6081:7b01:cbda:519a:4843:2801:9790]) by smtp.gmail.com with ESMTPSA id c68sm999392qkf.48.2021.08.25.15.06.07 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Wed, 25 Aug 2021 15:06:08 -0700 (PDT) Date: Wed, 25 Aug 2021 18:06:05 -0400 From: Tom Rini To: Mark Kettenis Cc: takahiro.akashi@linaro.org, sjg@chromium.org, manu@bidouilliste.com, u-boot@lists.denx.de, ilias.apalodimas@linaro.org, jaeckel-floss@eyet-services.de, michal.simek@xilinx.com, dennis@ausil.us, daniel.schwierzeck@gmail.com, lukas.auer@aisec.fraunhofer.de, jh80.chung@samsung.com, mbrugger@suse.com, peng.fan@nxp.com, swarren@nvidia.com, swarren@wwwdotorg.org Subject: Re: [PATCH 00/28] Initial implementation of bootmethod/bootflow Message-ID: <20210825220605.GB858@bill-the-cat> References: <20210819034601.1618773-1-sjg@chromium.org> <56140f0c4976b9f9@bloch.sibelius.xs4all.nl> <20210823200146.GG858@bill-the-cat> <561412964a77c660@bloch.sibelius.xs4all.nl> <20210825124523.abf62a19a25e7491a4b4dae1@bidouilliste.com> <20210825144251.GB89209@laputa> <20210825145635.GV858@bill-the-cat> <56141a22c6ddf02a@bloch.sibelius.xs4all.nl> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="cZ0XBXUSiF+GGV1x" Content-Disposition: inline In-Reply-To: <56141a22c6ddf02a@bloch.sibelius.xs4all.nl> X-Clacks-Overhead: GNU Terry Pratchett User-Agent: Mutt/1.9.4 (2018-02-28) X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.34 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.2 at phobos.denx.de X-Virus-Status: Clean --cZ0XBXUSiF+GGV1x Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Aug 25, 2021 at 11:54:58PM +0200, Mark Kettenis wrote: > > Date: Wed, 25 Aug 2021 10:56:35 -0400 > > From: Tom Rini > >=20 > > On Wed, Aug 25, 2021 at 11:42:51PM +0900, AKASHI Takahiro wrote: > > > Simon, > > >=20 > > > On Wed, Aug 25, 2021 at 07:11:44AM -0600, Simon Glass wrote: > > > > Hi, > > > >=20 > > > > On Wed, 25 Aug 2021 at 04:45, Emmanuel Vadot wrote: > > > > > > > > > > On Tue, 24 Aug 2021 12:22:42 +0200 (CEST) > > > > > Mark Kettenis wrote: > > > > > > > > > > > > Date: Mon, 23 Aug 2021 16:01:46 -0400 > > > > > > > From: Tom Rini > > > > > > > > > > > > > > On Mon, Aug 23, 2021 at 11:25:42AM -0600, Simon Glass wrote: > > > > > > > > Hi Mark, > > > > > > > > > > > > > > > > On Mon, 23 Aug 2021 at 05:54, Mark Kettenis wrote: > > > > > > > > > > > > > > > > > > > From: Simon Glass > > > > > > > > > > Date: Wed, 18 Aug 2021 21:45:33 -0600 > > > > > > > > > > > > > > > > > > > > Bootmethod and bootflow provide a built-in way for U-Bo= ot to automatically boot > > > > > > > > > > an Operating System without custom scripting and other = customisation: > > > > > > > > > > > > > > > > > > > > - bootmethod - a method to scan a device to find boot= flows (owned by U-Boot) > > > > > > > > > > - bootflow - a description of how to boot (owned by t= he distro) > > > > > > > > > > > > > > > > > > > > This series provides an initial implementation of these= , enable to scan > > > > > > > > > > for bootflows from MMC and Ethernet. The only bootflow = supported is > > > > > > > > > > distro boot, i.e. an extlinux.conf file included on a f= ilesystem or > > > > > > > > > > tftp server. It works similiarly to the existing script= -based approach, > > > > > > > > > > but is native to U-Boot. > > > > > > > > > > > > > > > > > > > > With this we can boot on a Raspberry Pi 3 with just one= command: > > > > > > > > > > > > > > > > > > > > bootflow scan -lb > > > > > > > > > > > > > > > > > > > > which means to scan, listing (-l) each bootflow and try= ing to boot each > > > > > > > > > > one (-b). The final patch shows this. > > > > > > > > > > > > > > > > > > > > It is intended that this approach be expanded to suppor= t mechanisms other > > > > > > > > > > than distro boot, including EFI-related ones. With a st= andard way to > > > > > > > > > > identify boot devices, these features become easier. It= also should > > > > > > > > > > support U-Boot scripts, for backwards compatibility onl= y. > > > > > > > > > > > > > > > > > > > > The first patch of this series moves boot-related code = out of common/ and > > > > > > > > > > into a new boot/ directory. This helps to collect these= related files > > > > > > > > > > in one place, as common/ is quite large. > > > > > > > > > > > > > > > > > > > > Like sysboot, this feature makes use of the existing PX= E implementation. > > > > > > > > > > Much of this series consists of cleaning up that code a= nd refactoring it > > > > > > > > > > into something closer to a module that can be called, t= easing apart its > > > > > > > > > > reliance on the command-line interpreter to access file= systems and the > > > > > > > > > > like. Also it now uses function arguments and its own c= ontext struct > > > > > > > > > > internally rather than environment variables, which is = very hard to > > > > > > > > > > follow. No core functional change is included in the in= cluded PXE patches. > > > > > > > > > > > > > > > > > > > > For documentation, see the 'doc' patch. > > > > > > > > > > > > > > > > > > > > There is quite a long list of future work included in t= he documentation. > > > > > > > > > > One question is the choice of naming. Since this is a b= ootloader, should > > > > > > > > > > we just call this a 'method' and a 'flow' ? The 'boot' = prefix is already > > > > > > > > > > shared by other commands like bootm, booti, etc. > > > > > > > > > > > > > > > > > > > > The design is described here: > > > > > > > > > > > > > > > > > > > > https://drive.google.com/file/d/1ggW0KJpUOR__vBkj3l61L2= dav4ZkNC12/view?usp=3Dsharing > > > > > > > > > > > > > > > > > > > > The series is available at u-boot-dm/bmea-working > > > > > > > > > > > > > > > > > > How does the user control the order in which devices are = scanned/booted? > > > > > > > > > > > > > > > > That is not supported in distroboot at present, at least so= far as I > > > > > > > > can see. For Fedora it seems to happen in grub. Do I have t= hat right? > > > > > > > > > > > > > > Well, there's "find the next stage", which is boot_targets en= vironment > > > > > > > variable, and then "where that next stage looks for stuff" wh= ich is > > > > > > > OS-dependent. Sometimes the ESP grub.cfg file is just enough= to tell > > > > > > > grub to find the full grub.cfg file elsewhere, and sometimes = it's a full > > > > > > > grub.cfg file. I think Mark is talking about the former, and= you've > > > > > > > said it's not part of this series, yet, but on the TODO list. > > > > > > > > > > > > Right. With the current distroboot code the order of the devic= es that > > > > > > appears in boot_targets is determined by per-board/SOC/machine = config > > > > > > files and the order isn't the same for all of them. Users can = change > > > > > > the order if necessary by modifying the environment variable and > > > > > > saving the environment. And for a one-off boot from a different > > > > > > device they can simply run an appropriate boot command. The > > > > > > boot_targets variable in particular is documented in various in= stall > > > > > > documents so it would probably be good of the new "bootmethod" = code > > > > > > would respect this variable. > > > > > > > > > > > > For OpenBSD I'm not really interested in the bootflow part. As= I > > > > > > explained in the past, that part of the problem is solved in a > > > > > > (mostly) uniform way across platforms by the OpenBSD bootloader= which > > > > > > can read an /etc/boot.conf that allows bootflow customization. = So as > > > > > > long as the default of the new code still results in > > > > > > \EFI\BOOT\BOOT{machine type short-name}.EFI being loaded and ru= n if > > > > > > there is no U-Boot specific bootflow configured, I'm happy. > > > > > > > > > > Mostly the same for FreeBSD, as long as the efi boot.efi is > > > > > loaded and run by default (respecting the boot_targets order) we = will > > > > > be fine. > > > >=20 > > > > OK thanks for the info. My expectation is that bootmethod/bootflow = can > > > > support this easily enough (it is actually simpler than distro boot= ). > > > >=20 > > > > > > > > > > > I can't speak for the other BSDs, but my impression is that the= y are > > > > > > pretty much in the same position. The FreeBSD bootloader for e= xample > > > > > > supports a high-degree of "bootflow" customization and I doubt = that > > > > > > taking it out of the loop is a viable option for most users. > > > >=20 > > > > I think the same may happen with grub. E.g. with Ubuntu I see quite= a > > > > bit of code in the grub.cfg file and it's not clear to me that it c= an > > > > be replaced with a 'data instead of code' approach. Still, a valid > > > > bootflow is simply to jump to an EFI app, which seems to be what is > > > > happening here. The bootflow side is really just about describing w= hat > > > > to do, and this case is no different. For now I see three types of > > > > bootflow, PXE/syslinux, EFI boot manager and EFI app. > > >=20 > > > By "EFI app", do you mean a way of booting "/efi/boot/bootXX.efi" > > > (default file name in case that no image path is specified)? > > >=20 > > > In fact, this behavior, or removable media support, is defined > > > as part of UEFI boot manager in UEFI specification. (See section 3.5) > > > What this means is that the boot order, including a removable media > > > case and user-provided BootXXXX cases, should be controlled solely > > > by "BootOrder" variable. > > > So the current combination of distro_bootcmd + UEFI boot manger doesn= 't > > > fully comply with the specification. > > >=20 > > > Even if those two cases are integrated, I don't know how "BootOrder" > > > semantics can be preserved in your approach. > >=20 > > I think the high level answer is that whereas today part of > > distro_bootcmd (and so iterating over boot_targets) "bootefi bootmgr" > > gets run, with what Simon is proposing we would have an easier / quicker > > way to get over to just running that. Perhaps a clean-up to just use > > that, even? Or are we not to the point yet where we could remove the > > direct fall-back to /efi/boot/bootXX.efi ? >=20 > I think "bootefi bootmgr" only works if the BootOrder variable is > defined, and currently that isn't the case. >=20 > The boot manager behaviour as specified in the UEFI specification is > somewhat problematic to implement in U-Boot because of the limitations > in how variables can be set at runtime. This is one of the reasons > OpenBSD doesn't actually bother with setting the variables and simple > relies on the "removable media" support mentioned above. All my > OpenBSD systems that use U-Boot print the follwing lines: >=20 > BootOrder not defined > EFI boot manager: Cannot load any image > Found EFI removable media binary efi/boot/bootaa64.efi >=20 > But maybe that last step can be intgrated into bootefi bootmgr at some > point? >=20 > Also note that manually manipulating the EFI variables to change the > boot order is quite cumbersome; it isn't a matter of just changed the > aforementioned BootOrder variable. That's why I think boot_targets is > the preferable way to define the order in which devices should be > booted. I don't think that violates the UEFI specification. It > merely is the way U-Boot implements the boot device selection that > more traditional UEFI implementations implement using a menu. As I don't want to side-track Simon's thread even further, I would like to see a bit more detailed explanation of why U-Boot cannot support EFI variables, or if it's just a matter of someone doing the work, and it's not been a priority yet. --=20 Tom --cZ0XBXUSiF+GGV1x Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQGzBAABCgAdFiEEGjx/cOCPqxcHgJu/FHw5/5Y0tywFAmEmvs0ACgkQFHw5/5Y0 tywmQgv/Y0dGQPhGdv24Q4L6YLqSg9YpPeUYg0Eoc8a5wmKcdL9ux8X9FJyCFT+G 4DlAvwcgBhoqw6rUVqipxFPckr0+clcvNDcELzfAuBuVHkEgiqZfJmWzRyU18lPf fcmMgnAGJIAYOjEfOZp5wAFX85nB0mRbZhS1CBLwcgtLl+CgpOn6pVB2huF8rdDO Dl++HKHWQEyRmqoV+vyOvboR85eRzoL8wyPhuEbtOpoutyOuQYWLq/Hf9yJBp75G bM27OyECxnoGTt5p3ecr1IJtu+Kj40mvpVObu6r5RKvKm0xuEpXz1+DF+sIvLQJ9 ETMGQh7sive+2OKHyWx4fNre9J8ll1krfKBu45TjpgyK9CRfggU8s4CDT8DEDrFs NXp24qxrMjq0W1ncAc7uD3Xt+QCK8jjcV26LCNwpnFzQbuYNRRQx3ErW57meypNx Q427GgDKaO1SBpWYGTXOSAmR/2VSWebckQwraYNPa4PFCn25xLsE8NjHtKaWGLvc RC5cEb09 =K8vZ -----END PGP SIGNATURE----- --cZ0XBXUSiF+GGV1x--