From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay3.corp.sgi.com [198.149.34.15]) by oss.sgi.com (Postfix) with ESMTP id 93A9F29DF8 for ; Mon, 6 May 2013 14:14:46 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay3.corp.sgi.com (Postfix) with ESMTP id 22DD6AC003 for ; Mon, 6 May 2013 12:14:42 -0700 (PDT) Received: from sandeen.net (sandeen.net [63.231.237.45]) by cuda.sgi.com with ESMTP id 8H4pXxFXHiVCDsAu for ; Mon, 06 May 2013 12:14:41 -0700 (PDT) Message-ID: <51880121.8000001@sandeen.net> Date: Mon, 06 May 2013 14:14:41 -0500 From: Eric Sandeen MIME-Version: 1.0 Subject: Re: Internal error xfs_sb_read_verify at line 726 References: <20130506112717.GA502@x4> <5187E290.8090109@sandeen.net> <20130506183020.GA513@x4> In-Reply-To: <20130506183020.GA513@x4> 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: Markus Trippelsdorf Cc: xfs@oss.sgi.com On 5/6/13 1:30 PM, Markus Trippelsdorf wrote: > On 2013.05.06 at 12:04 -0500, Eric Sandeen wrote: >> On 5/6/13 6:27 AM, Markus Trippelsdorf wrote: >>> Today I accidentally tried to mount my backup disk at /dev/sdc instead >>> of /dev/sdc1 and this is what happened: >>> >>> ... >>> EXT4-fs (sdc): VFS: Can't find ext4 filesystem >>> FAT-fs (sdc): bogus number of reserved sectors >>> FAT-fs (sdc): Can't find a valid FAT filesystem >>> FAT-fs (sdc): bogus number of reserved sectors >>> FAT-fs (sdc): Can't find a valid FAT filesystem >>> ISOFS: Unable to identify CD-ROM format. >>> XFS (sdc): bad magic number >>> ffff8800db620000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >>> ffff8800db620010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >>> ffff8800db620020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >>> ffff8800db620030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >>> XFS (sdc): Internal error xfs_sb_read_verify at line 726 of file fs/xfs/xfs_mount.c. Caller 0xffffffff8119e5cd >> >> This seems to be a recent regression. >> >> Comments above xfs_sb_quiet_read_verify() indicate that this behavior is >> to be avoided: >> >> * We may be probed for a filesystem match, so we may not want to emit >> * messages when the superblock buffer is not actually an XFS superblock. >> >> and it checks for proper magic prior to all the chattiness above int >> that function. >> >> The superblock read is suposed to choose whether to be noisy or not, >> in xfs_readsb(): >> > > The following patch fixes the issue for me: > > > diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c > index f6bfbd7..db8f27f 100644 > --- a/fs/xfs/xfs_mount.c > +++ b/fs/xfs/xfs_mount.c > @@ -721,6 +721,11 @@ xfs_sb_read_verify( > } > error = xfs_sb_verify(bp); > > + if (error == XFS_ERROR(EWRONGFS)) { > + xfs_buf_ioerror(bp, EWRONGFS); > + return; > + } > + > out_error: > if (error) { > XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); That might make sense, I don't think we need the loudness for EWRONGFS no matter how we got there. But: Out of curiosity, what was the actual mount command you used? It seems like the auto-probing should have set the MS_SILENT flag to avoid this in the first place, i.e. we should have gone down the quiet path (xfs_sb_quiet_read_verify) and avoided this altogether. How do you reproduce this? If I were to patch xfs_read_sb_verify, I'd probably do it like this: diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index f6bfbd7..7488335 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -723,7 +723,9 @@ xfs_sb_read_verify( out_error: if (error) { - XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); + if (error != EWRONGFS) + XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, + mp, bp->b_addr); xfs_buf_ioerror(bp, error); } } Because it keeps a single return point in the function, and . . . XFS_ERROR() is never used on the right side of a test; it's only to turn an error return into a BUG_ON for certain error numbers when they're set; i.e. it'd fire in xfs_mount_validate_sb before we ever got to the caller: xfs_warn(mp, "bad magic number"); return XFS_ERROR(EWRONGFS); /* would BUG if configured to do so */ Thanks, -Eric _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs