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From: Joao Carlos Mendes Luis <jonny@mailhost.coppe.ufrj.br>
Message-Id: <199610062048.SAA07079@mailhost.coppe.ufrj.br>
Subject: Found a BUG and partial solution (was: nullfs: Panicing...)
To: adam@veda.is (Adam David)
Date: Sun, 6 Oct 1996 18:48:10 -0200 (EDT)
Cc: jonny@mailhost.coppe.ufrj.br, freebsd-hackers@freebsd.org
In-Reply-To: <199610062030.UAA14571@veda.is> from Adam David at "Oct 6, 96 08:30:07 pm"
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#define quoting(Adam David)
// > // >PS: I'm now using NFS to localhost, as a workaround.
// > // 
// > // I had to abandon this approach and use symlinks instead, once the directory
// > // had outgrown a certain size. Perhaps there is no longer any such size limit,
// > // but I don't have the stomach at the moment to risk it.
// > 
// > I cannot symlink to anon ftp.  It's chrooted, remember ?  :)
// 
// You can symlink in the other direction, but perhaps that is not appropriate
// for your particular situation. It might at least be acceptable, though less
// than convenient.

Disk Space, the final frontier.  These are the voyages of the StarShip BSD.
:-)

  Analysing the sources I found the (first) point of failure: Seens to me
that there's a line missing near the end of nullfs_mount() calling
nullfs_statfs( mp, &mp->mnt_stat, p );  It's strange, since nullfs_statfs()
has a check to verify if it has been called this way...  The problem was
caused by a division by zero at vnode_pager_haspage(), line 313:

	block = offset / vp->v_mount->mnt_stat.f_iosize;
					       ^^^^^^^^

  But yet, it still does not work.  Now it's a problem of page fault
while in kernel mode.  My knowledge of BSD internals is not enough
to find the problem anymore...

					Jonny

PS: I'm talking about the sources of 2.1.5-RELEASE

--
Joao Carlos Mendes Luis			jonny@gta.ufrj.br
+55 21 290-4698 ( Job )			jonny@cisi.coppe.ufrj.br
Network Manager				UFRJ/COPPE/CISI
Universidade Federal do Rio de Janeiro