Re: kernel oops: trying to mount a corrupted xfs partition (2.6.16-rc3)

[Sonny Rao <sonny@burdell.org>]

On Tue, Feb 21, 2006 at 01:04:47PM +1100, Nathan Scott wrote:
> On Mon, Feb 20, 2006 at 02:09:16AM -0500, Sonny Rao wrote:
> > On Sun, Feb 19, 2006 at 04:52:09PM -0500, Dave Jones wrote:
> > <snip> 
> > > Just for kicks, I just hacked this up..
> > > 
> > > #!/bin/bash
> > > wget http://www.digitaldwarf.be/products/mangle.c
> > > gcc mangle.c -o mangle
> > > 
> > > dd if=/dev/zero of=data.img count=70000
> > > 
> > > while [ 1 ];
> > > do
> > >         mkfs.xfs -f data.img >/dev/null
> > > 		./mangle data.img $RANDOM
> > >         sudo mount -t xfs data.img mntpt -o loop
> > >         sudo ls -R mntpt
> > >         sudo umount mntpt
> > > done
> > ...
> > > 
> > > xfs wins the award for 'noisiest fs in the face of corruption' :-)
> > > After a few dozen backtraces from xfs_corruption_error,
> > > this fell out...
> > > 
> > > divide error: 0000 [1] SMP
> > <snip trace>
> >  
> > > (The kernel is based on 2.6.16rc4)
> > 
> > I see a similar breakage (divide error) on x86 using 2.6.15
> 
> From a quick look at the image you sent me Sonny, I guess this is
> the same problem Dave was seeing too -- a divide by zero when we're
> working out some of the per-mount constants during mount(2).  There
> is probably one or two other superblock fields that could use more
> verification, but this will do for now.

yep, this patch fixes it

Sonny