From owner-freebsd-current@freebsd.org Tue Dec 19 19:26:33 2017 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id F0B1AE9A11A for ; Tue, 19 Dec 2017 19:26:33 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: from asp.reflexion.net (outbound-mail-210-99.reflexion.net [208.70.210.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 9C55667468 for ; Tue, 19 Dec 2017 19:26:33 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: (qmail 29672 invoked from network); 19 Dec 2017 19:26:26 -0000 Received: from unknown (HELO mail-cs-01.app.dca.reflexion.local) (10.81.19.1) by 0 (rfx-qmail) with SMTP; 19 Dec 2017 19:26:26 -0000 Received: by mail-cs-01.app.dca.reflexion.local (Reflexion email security v8.40.3) with SMTP; Tue, 19 Dec 2017 14:26:26 -0500 (EST) Received: (qmail 20200 invoked from network); 19 Dec 2017 19:26:26 -0000 Received: from unknown (HELO iron2.pdx.net) (69.64.224.71) by 0 (rfx-qmail) with (AES256-SHA encrypted) SMTP; 19 Dec 2017 19:26:26 -0000 Received: from [192.168.1.25] (c-76-115-7-162.hsd1.or.comcast.net [76.115.7.162]) by iron2.pdx.net (Postfix) with ESMTPSA id 8B6ECEC9378; Tue, 19 Dec 2017 11:26:25 -0800 (PST) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 10.3 \(3273\)) Subject: Re: UEFI booting survey From: Mark Millard In-Reply-To: Date: Tue, 19 Dec 2017 11:26:25 -0800 Cc: FreeBSD Current Content-Transfer-Encoding: quoted-printable Message-Id: References: <60C20606-853E-43AE-9F90-44C65026A098@dsl-only.net> To: Warner Losh X-Mailer: Apple Mail (2.3273) X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 19 Dec 2017 19:26:34 -0000 [I forgot to list the .dtb file with the kernel and world.] On 2017-Dec-19, at 9:58 AM, Mark Millard wrote: > On 2017-Dec-18, at 2:37 PM, Warner Losh wrote: >=20 >> . . . >>=20 >> Or the following pseudo-code with all the weird special cases removed = for clarity >>=20 >> load loader.efi from ESP >> if BootXXXX uefi variable holds a second path, use that for = root/kernel >> otherwise if an override variable holds a kernel/root path, use that >> otherwise scan for a usable ZFS pool, use that if it exists >> otherwise use the same partition loader.efi was booted from for = root/kernel if it's usable >> otherwise use the first UFS partition on the ESP that's usable. >>=20 >> A partition is usable if /boot/loader.rc exists on that path. >=20 > What will be the role of /etc/fstab in establishing > were the kernel is loaded from? Where world is > loaded from? Where/how does use of /etc/fstab for > specifying the root file system mount fit in the > above pseudo-code? Typo: should be "establishing where". > (For my particular interest the context uses UFS, not > ZFS.) I forgot to list: What will be the role of /etc/fstab in establishing where the .dtb file will be found (when such is involved)? >> What is being deleted is one final step: "otherwise use the first UFS = partition on any drive in a random order that's usable." which used to = be at the end of the boot1.efi psuedo code. It's my belief that no such = installations actually use this due to the random factor today (plug in = a new USB drive and it might take over). If my belief is wrong, it's my = belief that efibootmgr will solve it, and failing that, the fallback = mechanism (for platforms that use u-boot + EFI where UEFI variables = don't work) will allow the two or three people that are doing this = today. =3D=3D=3D Mark Millard markmi at dsl-only.net