Re: panic: ffs_snapshot_mount: already on list

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Wed, Sep 12, 2018 at 09:37:46AM +0000, Emmanuel Dreyfus wrote:
> On Wed, Sep 12, 2018 at 09:48:21AM +0200, Manuel Bouyer wrote:
> > Yes, IHMO it should not panic but complains and ignore the invalid snapshots.
> > In your case you had to mount the FS read/write to fix the problem
> > (I guess you could have fixed it with fsdb+fsck too, but we should not have
> > to go there to go back to a mountable filesystem).
> 
> Something like this? (I retained the #ifndef FFS_NO_SNAPSHOT which 
> saved my day)
> --- sys/ufs/ffs/ffs_snapshot.c.orig
> +++ sys/ufs/ffs/ffs_snapshot.c
> @@ -1734,8 +1734,9 @@
>   */
>  void
>  ffs_snapshot_mount(struct mount *mp)
>  {
> +#ifndef FFS_NO_SNAPSHOT
>         struct vnode *devvp = VFSTOUFS(mp)->um_devvp;
>         struct fs *fs = VFSTOUFS(mp)->um_fs;
>         struct lwp *l = curlwp;
>         struct vnode *vp;
> @@ -1823,14 +1824,15 @@
>  
>                 /*
>                  * Link it onto the active snapshot list.
>                  */
> -               if (is_active_snapshot(si, ip))
> -                       panic("ffs_snapshot_mount: %"PRIu64" already on list",
> +               if (is_active_snapshot(si, ip)) {
> +                       printf("ffs_snapshot_mount: %"PRIu64" already on list",
>                             ip->i_number);

maybe clear fs->fs_snapinum[snaploc] in that case ?

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--