Re: 2.6.28.9: EXT3/NFS inodes corruption

[Jan Kara]

   Hi,

On Tue 04-08-09 13:15:05, Sylvain Rochet wrote:
> On Tue, Aug 04, 2009 at 12:29:01AM +0200, Jan Kara wrote:
> > 
> >   OK, I've found some time and written the debugging patch. Hopefully it
> > will tell us more. It should output messages to the kernel log if it
> > finds something suspicious - like:
> > No dentry for unlinked inode...
> > Dentry ... for unlinked inode ... has no parent
> > Found directory entry ... for unlinked inode
> > 
> >   When you see such messages in the log, send them to me please. Also
> > attach the System.map file so that I can translate the address where
> > i_nlink was dropped - for that ext3 should be compiled into the kernel
> > (should not be a module). Thanks a lot for testing.
> 
> Patch applied.
> 
> And there is already a lot of output.
> 
> http://edony.tuxfamily.org/~grad/bazooka/System.map-2.6.30.4
> http://edony.tuxfamily.org/~grad/bazooka/config-2.6.30.4
> http://edony.tuxfamily.org/~grad/bazooka/kern.log
  Thanks for testing. So you seem to be really stressting the path where
creation of new files / directories fails (probably due to group quota).  I
have one idea what could cause your filesystem corruption, although it's a
wild guess... Please try attached oneliner.
  Also your corruption reminded me that Al Viro has been fixing problems
where we could cache one inode twice when a filesystem was mounted over NFS
and that could also lead to a filesystem corruption. So I'm adding him to
CC just in case he has some idea. BTW Al, what do you think about the
problem I describe in the attached patch? I'm not sure if it can cause some
real problems but in theory it could...

								Honza
-- 
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR