Re: 2.6.17-ck1: fcache problem...

[Jens Axboe <axboe@suse.de>]

On Tue, Jun 27 2006, Paolo Ornati wrote:
> On Sun, 25 Jun 2006 19:43:59 +0200
> Jens Axboe <axboe@suse.de> wrote:
> 
> > > > Hmm, and you are sure that the fs is properly umounted on reboot? Or is
> > > > it just remounted ro? It looks like fcache_close_dev() isn't being
> > > > called, so the cache serial doesn't match what we expect from the fs,
> > > > hence fcache bails out since it could indicate that the fs has been
> > > > changed without fcache being attached.
> > > 
> > > Ahh... it is the root fs and it's just remounted read-only by the
> > > standard Gentoo scripts ;)
> > > 
> > > I don't think that unmounting it is trivial (you need to chroot to a
> > > virtual FS or something...). Does any distro do it?
> > 
> > ro should be enough, something odd must be going on. I'll add it to the
> > list of things to test tomorrow.
> 
> Since "fcache_close_dev()" is called by "ext3_put_super()" I have added
> this stupid printk:
> 
> --- fs/ext3/super.c.orig        2006-06-27 10:47:15.000000000 +0200
> +++ fs/ext3/super.c     2006-06-27 10:50:36.000000000 +0200
> @@ -422,6 +422,8 @@ static void ext3_put_super (struct super
> 
>         has_fcache = test_opt(sb, FCACHE);
> 
> +       printk("!!! ext3_put_super !!!   has_fcache=%d\n", has_fcache);
> +
>         ext3_xattr_put_super(sb);
>         journal_destroy(sbi->s_journal);
>         if (!(sb->s_flags & MS_RDONLY)) {
> 
> 
> It triggers on unmount but it doesn't on remount "ro".
> 
> So the problem is that "fcache_close_dev()" have zero chances to run ;)

Hmm, you seem to be using an older fcache version. I'll test this and
post an updated patch if it doesn't work with the newer version.

-- 
Jens Axboe