[Top] [All Lists]

RE: oops umounting full LVM snapshots

To: "'Eric Sandeen'" <sandeen@xxxxxxx>, Steve Lord <lord@xxxxxxx>
Subject: RE: oops umounting full LVM snapshots
From: "Stephenson, Dale" <dstephenson@xxxxxxxxxxxxxx>
Date: Wed, 27 Feb 2002 11:25:06 -0800
Cc: "Xfs \"Mailing List (E-mail)" <linux-xfs@xxxxxxxxxxx>
Sender: owner-linux-xfs@xxxxxxxxxxx
Eric Sandeen wrote:
> FWIW, it's even simpler to show the problem, it's not necessary to
> overflow the snapshot or even copy anything to them.  Just create a
> couple snapshot volumes, mount them, and unmount them.  Unmounting the
> first snapshot does a forced shutdown, unmounting the second 
> one does a
> force shutdown and then oopses.
FWIW, I was able to oops by mounting/umounting snapshots using 2.4.16 with
LVM 1.0.2.  I was able to work around the problem by changing the snapshot
to writeable (using a writeable snapshot patch)--that let the force shutdown
do whatever it wanted to do to the "read only" file system, and no I/O error
was returning.  I was able to SOLVE the problem by using a different
compiler.  By compiling with kgcc instead of gcc 2.96, the
mount/umount/mount/umount no longer created oops.  The unmounting full LVM
snapshot problem remained the same, however.

With 2.4.17 and LVM 1.0.3 (and no other LVM/IDE/xfs patches), I can mount
and unmount a snapshot ten times in succession without oops or forced
shutdown--compiled with kgcc.  I expect that with gcc I would see the
behavior you describe.

Dale Stephenson

<Prev in Thread] Current Thread [Next in Thread>