From owner-freebsd-hackers@freebsd.org Sun Apr 29 18:21:21 2018 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B6F4FFB4129 for ; Sun, 29 Apr 2018 18:21:21 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: from mail-it0-x22b.google.com (mail-it0-x22b.google.com [IPv6:2607:f8b0:4001:c0b::22b]) (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 4D5B06D7BE for ; Sun, 29 Apr 2018 18:21:21 +0000 (UTC) (envelope-from wlosh@bsdimp.com) Received: by mail-it0-x22b.google.com with SMTP id p3-v6so7603895itc.0 for ; Sun, 29 Apr 2018 11:21:21 -0700 (PDT) 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=uABNZlQvDTp99jAU0v/nbxCtH4T5u38kO+tuOl5zvH8=; b=yZPVXaXgSzpTdA4IjfpjuzIEeEOifcJQ9RPJXlvLaUY2TByF9sJGEGYQfZAlt/vGsf eimtteFiq/J2+cUeexeCsJn34WRF52ZazyvUMURATmjpajXmq+HILBlByCaZSfvAQUv0 6guabEV6NSPQgKEtDfH9h+aE0SYvT2lmIUXDWRJBVCLoqcrRwmnmCJHYO5EzPu2a/4aR wa5Gqrm0OWt6rUZF7Ia9/OY7BNamaHQqiXrygNxiViBC9TRRYoeNRxdBkLbBQP/joeHR cwnD9S/9m4JpjIPc+WC1c/GYxQx/z4IEhtgr4o7HrfcJj309z5Rb7ildQ3oo+KDoB5vA 3www== 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=uABNZlQvDTp99jAU0v/nbxCtH4T5u38kO+tuOl5zvH8=; b=mVQRaKgJ5RojVpOKgyYswN7pc66SPTyA9oMSGMshHrlBgaWZYdzQa+jPS2PHPXRJxz q7KQXwPKQJp1AC9ZBquKfYf2QBii8st8Ubkp/u21VQtP+iYgt/RYuE/MTnONrr/ZHtU7 rz6OsPSbpLKCYp3YahfJnKeNWntEO/qm4V9asU+gagSLLlz5LQ154eOivds6oj6VK/H9 zceUXFyBkR4IaEdSByNzECf56j+K/A5VE4DjaZqVzErgPR3SkHLNZCKTkU+/waxrX6AA ZwO2wPZoMLEmeSN9nFip37CUb2U59hQReJ86Y7jrgj2xo+JoZ/JrbG9szIFk1pa3ZUzl iaqg== X-Gm-Message-State: ALQs6tADDoQF8dgvvpbxixsgSNGFymKtXycd7ixlzU/Mihal4/6OJ+gQ ji5aoUBLGrZ8eWwmPleiDAQD9Ky5Cs6+IS8ptlIMCA== X-Google-Smtp-Source: AB8JxZqANCpXB7sMqxVnhd+G8Lvnkji1U6D7EyzJV8ml3N7IIO5sYa7++hXdj4nbsnJRjvZ91O/i+rZimOOL3VeR38E= X-Received: by 2002:a24:42c6:: with SMTP id i189-v6mr9343932itb.73.1525026080498; Sun, 29 Apr 2018 11:21:20 -0700 (PDT) MIME-Version: 1.0 Sender: wlosh@bsdimp.com Received: by 2002:a4f:a65a:0:0:0:0:0 with HTTP; Sun, 29 Apr 2018 11:21:19 -0700 (PDT) X-Originating-IP: [2603:300b:6:5100:1052:acc7:f9de:2b6d] In-Reply-To: <07576f68-f67e-3a22-7a50-ff261c9b3fff@digitaldaemon.com> References: <5f836c79-b379-f066-689b-1645e393c5e9@digiware.nl> <1645b168-4133-693c-2dd3-8e0606abb9c3@digiware.nl> <07576f68-f67e-3a22-7a50-ff261c9b3fff@digitaldaemon.com> From: Warner Losh Date: Sun, 29 Apr 2018 12:21:19 -0600 X-Google-Sender-Auth: pkzFlqKdzugInV083a6N0Rw8uwQ Message-ID: Subject: Re: Getting ZFS pools back. To: Jan Knepper Cc: Willem Jan Withagen , Alan Somers , FreeBSD Filesystems , FreeBSD Hackers , Richard Yao Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.25 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 29 Apr 2018 18:21:22 -0000 On Sun, Apr 29, 2018 at 11:57 AM, Jan Knepper wrote: > On 04/29/2018 13:27, Willem Jan Withagen wrote: > >> Trouble started when I installed (freebsd-update) 11.1 over a running >> 10.4. Which is sort of scarry? >> > This does sounds 'scary' as I am planning to do this in the (near) > future... > > Has anyone else experienced issues like this? > > Generally I do build the new system software on a running system, but then > go to single user mode to perform the actual install. > > I have done many upgrades like that over 18 or so years and never seen or > heard of an issue alike this. 11.x binaries aren't guaranteed to work with a 10.x kernel. So that's a bit of a problem. freebsd-update shouldn't have let you do that either. However, most 11.x binaries work well enough to at least bootstrap / fix problems if booted on a 10.x kernel due to targeted forward compatibility. You shouldn't count on it for long, but it generally won't totally brick your box. In the past, and I believe this is still true, they work well enough to compile and install a new kernel after pulling sources. The 10.x -> 11.x syscall changes are such that you should be fine. At least if you are on UFS. However, the ZFS ioctls and such are in the bag of 'don't specifically guarantee and also they change a lot' so that may be why you can't mount ZFS by UUID. I've not checked to see if there's specifically an issue here or not. The ZFS ABI is somewhat more fragile than other parts of the system, so you may have issues here. If all else fails, you may be able to PXE boot an 11 kernel, or boot off a USB memstick image to install a kernel. Generally, while we don't guarantee forward compatibility (running newer binaries on older kernels), we've generally built enough forward compat so that things work well enough to complete the upgrade. That's why you haven't hit an issue in 18 years of upgrading. However, the velocity of syscall additions has increased, and we've gone from fairly stable (stale?) ABIs for UFS to a more dynamic one for ZFS where backwards compat is a bit of a crap shoot and forward compat isn't really there at all. That's likely why you've hit a speed bump here. Warner