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Date: Mon, 18 Feb 2008 18:26:17 -0800 (PST)
From: Matthew Dillon <dillon@apollo.backplane.com>
Message-Id: <200802190226.m1J2QHNI093023@apollo.backplane.com>
To: Jim Bryant <freebsd@electron-tube.net>
References: <47B90868.7000900@electron-tube.net>
	<86odae5rgr.fsf@ds4.des.no>	<863arq5q14.fsf@ds4.des.no>
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Cc: freebsd-fs@freebsd.org, freebsd-stable@freebsd.org
Subject: Re: How to take down a system to the point of requiring a
	newfs	with one line of C (userland)
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    Jim's original report seemed to indicate that the filesystem paniced
    on mount even after repeated fsck's.

    That implies that Jim has a filesystem image that panics on mount. 
    Maybe Jim can make that image available and a few people can see if
    downloading and mounting it reproduces the problem.  It would narrow
    things down anyhow.

    Also, I didn't see a system backtrace anywhere.  If it paniced, where
    did it panic?

    The first thing that came to my mind was the dirhash code, but simply
    mounting a filesystem doesn't scan the mount point directory at all,
    except possibly for '.' or '..'... I don't think it even does that.  All
    it does is resolve the root inode of the filesystem.  The code path
    for mounting a UFS or UFS2 filesystem is very short.

						-Matt