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=-1.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 403B9C04AAF for ; Thu, 16 May 2019 21:39:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 012182070D for ; Thu, 16 May 2019 21:39:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=colorremedies-com.20150623.gappssmtp.com header.i=@colorremedies-com.20150623.gappssmtp.com header.b="tf5hLVSS" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728729AbfEPVjW (ORCPT ); Thu, 16 May 2019 17:39:22 -0400 Received: from mail-lf1-f46.google.com ([209.85.167.46]:40994 "EHLO mail-lf1-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726812AbfEPVjV (ORCPT ); Thu, 16 May 2019 17:39:21 -0400 Received: by mail-lf1-f46.google.com with SMTP id d8so3770639lfb.8 for ; Thu, 16 May 2019 14:39:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=colorremedies-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Q9vrZnSp0S/TSaXi62se9wEjsKFSJekv14/1CaCcnBI=; b=tf5hLVSS3M86YeRb6lcfwTbY34iJw9Br8pcO8Nl053NB2qRRNHA9Z4Lt6XKJjZSxJG SJdTa5fwFzE5lKK3KFR4sXm0yjQz9ey6MJsk88rmGFcAXbcZL2HkrpqhiNb5JZhwwED9 8byxVhDDobrkJKIsJIsPRJnUwu6lIrJnEDhZ9iQq8Gtlf07kaONRZz05cCy5uMmrs9vm oRAsbHvk9xaeBS7HoEJ2a2UlLcLRFIuvmBJByaKupnBbomk/RLu+H3ZjJZI0Ye3h/ILq wNbdwSIgEoLX9nia/5ElMqNn+2yFwRzVadDpgdd1x6/DA6DGSCK71AUiVGlgud2D1VJD lvIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Q9vrZnSp0S/TSaXi62se9wEjsKFSJekv14/1CaCcnBI=; b=rurcVpUgoNCgYT6TyAN47JSC1nfkbT0xyLL20ZpsAcDukrnv51lLq5Ef+sMJWcB1lS T/XqcF4w7XS+3JyieEjqhdgF6QBT2H8s+qk5SAD7yTTP6OLIoasWVfMYgDF7/NKloIKI goQeg8wDcdRgqq2MJZyH83YEhNDk2oo7EpBQ86CEBJjRgi68Used+x4/vd+9NGxmdwl+ SqzJ3lDVPqOYbuylF0wpDgoV+xI1NLBbuE+XCv2iMXHQP1y+wJGzKnRQZFUWxDB7ohyD rqCpL20UB1i/rnWlWlIlYE5JQBpgRzCSjZR41tN47TB+1ujI2GTP0MRs5qWVVfvz8b6i UUog== X-Gm-Message-State: APjAAAW5I9llErfVafqddeegHupXFrRKoalivMZgF0blNtRoSlCozjHo bc22XCD5yyJqj2nmbKP0hBXJ/9a80D2c/1WI1czuRI9cEHk= X-Google-Smtp-Source: APXvYqySqkK+ZbX3SpQLV+8RlWZCP1jIw125HVrSRXHkaVrO+Vf/0D0AZAqDW5IOmsKW4s2CGTMBuEK7Aod2qfIcdwk= X-Received: by 2002:ac2:4571:: with SMTP id k17mr26416755lfm.133.1558042759886; Thu, 16 May 2019 14:39:19 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Chris Murphy Date: Thu, 16 May 2019 15:39:08 -0600 Message-ID: Subject: Re: Unbootable root btrfs To: Lee Fleming Cc: Btrfs BTRFS Content-Type: text/plain; charset="UTF-8" Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Thu, May 16, 2019 at 4:37 AM Lee Fleming wrote: > And a btrfs check gives the following: > > % btrfs check --repair /dev/mapper/vg-root Why use repair? From the man page Warning Do not use --repair unless you are advised to do so by a developer or an experienced user > [ 17.429845] BTRFS error (device dm-1): failed to read block groups: -5 > [ 17.450035] BTRFS error (device dm-1): open_ctree failed Was there a crash or powerfailure during write before the problem started? What precipitated the problem? It might be possible to successfully mount with '-o ro,nologreplay,degraded' If that works, I'd take the opportunity to refresh backups. I'm not sure if this can be repaired but also not sure what the problem is. If it doesn't work, then the next step until a developer has an opinion on it, is 'btrfs restore' which is a way to scrape data out of an unmountable file system. It's better than nothing if the data is important, but ideal if at least ro mount can work. -- Chris Murphy