From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id 283557F66 for ; Tue, 7 Apr 2015 08:37:25 -0500 (CDT) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay2.corp.sgi.com (Postfix) with ESMTP id 1793F3041F0 for ; Tue, 7 Apr 2015 06:37:22 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id aYk3pIL2NHCUd0ox (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Tue, 07 Apr 2015 06:37:21 -0700 (PDT) Date: Tue, 7 Apr 2015 09:37:14 -0400 From: Brian Foster Subject: Re: [PATCH] xfs_db: disallow sb UUID write on v5 filesystems Message-ID: <20150407133714.GE23208@bfoster.bfoster> References: <5522A0DB.2010309@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <5522A0DB.2010309@redhat.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Eric Sandeen Cc: 782012@bugs.debian.org, xfs-oss On Mon, Apr 06, 2015 at 10:06:03AM -0500, Eric Sandeen wrote: > Do not allow xfs_db (or the xfs_admin frontend) to change the UUID > of a V5 filesystem; this will cause UUID mismatches across the > filesystem, and we currently have no mechanism to update them all. > Changing only the superblock UUID makes all other metadata look > invalid, and xfs_repair reacts by junking everything. > > Addresses-Debian-Bug: 782012 > Reported-by: F. Stoyan > Signed-off-by: Eric Sandeen > --- > > diff --git a/db/sb.c b/db/sb.c > index 6cb665d..f31f4a2 100644 > --- a/db/sb.c > +++ b/db/sb.c > @@ -363,6 +363,18 @@ uuid_f( > return 0; > } > > + /* > + * For now, changing the UUID of V5 superblock filesystems is > + * not supported; we do not have the infrastructure to fix all > + * other metadata when a new superblock UUID is generated. > + */ Unaligned start of comment above. :) Otherwise looks fine to me: Reviewed-by: Brian Foster > + if (xfs_sb_version_hascrc(&mp->m_sb) && > + strcasecmp(argv[1], "rewrite")) { > + dbprintf(_("%s: only 'rewrite' supported on V5 fs\n"), > + progname); > + return 0; > + } > + > if (!strcasecmp(argv[1], "generate")) { > platform_uuid_generate(&uu); > } else if (!strcasecmp(argv[1], "nil")) { > > _______________________________________________ > xfs mailing list > xfs@oss.sgi.com > http://oss.sgi.com/mailman/listinfo/xfs _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs