On Wed, May 11, 2022 at 11:06:51AM +1000, Dave Chinner wrote:
> On Tue, May 10, 2022 at 04:12:34PM -0700, Darrick J. Wong wrote:
> > On Mon, May 09, 2022 at 10:41:25AM +1000, Dave Chinner wrote:
> > > diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
> > > index c9c867e3406c..ad52b5dc59e4 100644
> > > --- a/fs/xfs/libxfs/xfs_attr.h
> > > +++ b/fs/xfs/libxfs/xfs_attr.h
> > > @@ -530,4 +553,35 @@ void xfs_attri_destroy_cache(void);
> > > int __init xfs_attrd_init_cache(void);
> > > void xfs_attrd_destroy_cache(void);
> > >
> > > +/*
> > > + * Check to see if the attr should be upgraded from non-existent or shortform to
> > > + * single-leaf-block attribute list.
> > > + */
> > > +static inline bool
> > > +xfs_attr_is_shortform(
> > > + struct xfs_inode *ip)
> > > +{
> > > + return ip->i_afp->if_format == XFS_DINODE_FMT_LOCAL ||
> > > + (ip->i_afp->if_format == XFS_DINODE_FMT_EXTENTS &&
> > > + ip->i_afp->if_nextents == 0);
> > > +}
> > > +
> > > +static inline enum xfs_delattr_state
> > > +xfs_attr_init_add_state(struct xfs_da_args *args)
> > > +{
> > > + if (!args->dp->i_afp)
> > > + return XFS_DAS_DONE;
> >
> > If we're in add/replace attr call without an attr fork, why do we go
> > straight to finished?
>
> I suspect I've fixed all the issues that triggered crashes here
> because args->dp->i_afp was null. THere were transient states in a
> replace operaiton when the remove takes away the last attr, removes
> the attr fork, then calls the ADD operation. The add operation
> assumes that the attr fork has already been set up, and so bad
> things happened here.
>
> This also occurred when setting up recovery operations - recovery of
> an add/replace could start from that same "there's no attr fork"
> condition, and so calling xfs_inode_has_attr() or
> xfs_attr_is_shortform() direct from the reocovery setup code would
> go splat because ip->i_afp was null.
>
> I'm going to leave this for the moment (cleanup note made) because I
> don't want to have to find out that I missed a corner case somewhere
> they hard way right now. It's basically there to stop log recovery
> crashing hard, which only occurs when the experimental larp code is
> running, so I think this is safe to leave for a later cleanup.
Hmm, in that case, can this become:
if (!args->dp->i_afp) {
ASSERT(0);
return XFS_DAS_DONE;
}
And then you can add:
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
> Cheers,
>
> Dave.
> --
> Dave Chinner
> david@xxxxxxxxxxxxx
