From owner-freebsd-current@freebsd.org Tue Dec 19 21:51:26 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 C7D13EA2E63 for ; Tue, 19 Dec 2017 21:51:26 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-io0-x231.google.com (mail-io0-x231.google.com [IPv6:2607:f8b0:4001:c06::231]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 88E806D2FB for ; Tue, 19 Dec 2017 21:51:26 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-io0-x231.google.com with SMTP id t196so15150736iof.0 for ; Tue, 19 Dec 2017 13:51:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bsdimp-com.20150623.gappssmtp.com; s=20150623; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=tDfOIn8ZBWPYEL5OIa3So0GErUrme1azoB9O0r5fonI=; b=wFCArLgnxdbpwdrTKKxOr7LrGjl2WwGdXDBHMXjZT1xEnp0vwmjNPcSWOmwlUjAru8 tMrZja1Ob6aAC3spx8CRUEnrO7DobFUpjDswVYuhccTBzsvqNmGb6Xfv0KwBQVI3N5Ms z8k88TYRD+dewr3zLJ04Zlh5bjIyAaQw5VD/70a8qBteH1/DN8f3iuKaurIsIgXpMJkZ Ed+cPLBXjHT4jeCPqeWsaz0mCKyZU1bc3Vcjo0jS6opAzGR/Rf72qQLF4e06tO16DTxZ TNEe2cseIVh4o4lDMkrTbr4y4qcjSHSt/FuPugoTPRFOZ7WTqp0Lt5BNJsYmiRNVPj2z S8ZQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=tDfOIn8ZBWPYEL5OIa3So0GErUrme1azoB9O0r5fonI=; b=QGW937chQFcaoT8+EBflCcPASMmQAkxPYKg0/iwkkLO02NTKBKtIGob4996c9OGet5 6L3IaPBokauKqZ1lSlT+HPr60jBZ2JDSxzPNsfaOkbyOuuubrWpt4GjorJpWRye2iegK 3NASUdl9nP4Wmt+OKa9PBSt7tZjGHmSCxNyRTB3qceTE9aUaW33LcTTVIxOYxAgj/txS K2NQwm6J4GuE/HS+wg00FTpOJezGaTJh9XBSWAFsQwfgqFWPMYmRpLLb82uHVxa/blVJ mQf75IccmDhTKqZm5xNEbmUgoxqWGca2d03RZW92YHEt98+/c1I1FB3gYae+QnQZ1IHH S+SA== X-Gm-Message-State: AKGB3mIjukUU4g0R0TxNKqPKQ1j3aEQduGE//5GzvcEy0VtX8dMnDhYU T3ytX/JRypw56RJc0tDHcvrnzrlHjxEpVA9WmqYxDQ== X-Google-Smtp-Source: ACJfBotarUhbpXaFfI3pVBr561qzVP7bG9ITq6aIkXpaC0kpH0ZjaNDh3qh2cUKpKu8amv8DWQggMvPd+2tmh8wk4kE= X-Received: by 10.107.18.35 with SMTP id a35mr1549251ioj.291.1513720285823; Tue, 19 Dec 2017 13:51:25 -0800 (PST) MIME-Version: 1.0 Sender: wlosh@bsdimp.com Received: by 10.79.108.204 with HTTP; Tue, 19 Dec 2017 13:51:24 -0800 (PST) X-Originating-IP: [2607:fb90:6f6a:13fc:4073:f971:9d8e:a305] Received: by 10.79.108.204 with HTTP; Tue, 19 Dec 2017 13:51:24 -0800 (PST) In-Reply-To: References: <60C20606-853E-43AE-9F90-44C65026A098@dsl-only.net> From: Warner Losh Date: Tue, 19 Dec 2017 14:51:24 -0700 X-Google-Sender-Auth: Xjd7NcNEmEdRipYEkPv7V-nR9yM Message-ID: Subject: Re: UEFI booting survey To: Mark Millard Cc: FreeBSD Current Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 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 21:51:26 -0000 On Dec 19, 2017 12:26 PM, "Mark Millard" wrote: [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: > >> . . . >> >> Or the following pseudo-code with all the weird special cases removed for clarity >> >> 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. >> >> A partition is usable if /boot/loader.rc exists on that path. > > 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)? None. See my prior message for why. Warner >> 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. === Mark Millard markmi at dsl-only.net