Re: [PATCH 01/24] lustre: rip the private symlink nesting limit out

Al Viro
2015-04-20T20:35:51Z

On Mon, Apr 20, 2015 at 08:22:53PM +0100, Al Viro wrote:
> On Mon, Apr 20, 2015 at 01:08:16PM -0600, Andreas Dilger wrote:
> > On Apr 20, 2015, at 12:12 PM, Al Viro <viro@ZenIV.linux.org.uk> wrote:
> > >
> > > From: Al Viro <viro@zeniv.linux.org.uk>
> > >
> > > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
> >
> > Al, the patch itself looks good, thanks.
> >
> > However, if this is applied at the start of the series it could
> > allow tests to easily cause a stack overflow during a bisection (I
> > don't think users would see a kernel in the middle of the series).
> >
> > Could this be converted over to checking nd->link_count along with
> > the [02/24] patch until closer to the end of the series when the
> > recursion has been removed?
>
> Er... You do realize that struct nameidata is opaque for anything outside
> of fs/namei.c and has been that way for a while now? Sure, we can export
> a helper that would return that and rip it out in the end of the series,
> but...

Actually, a cleaner solution would be to reorder that bunch (1--6) past
the link_path_walk() reorganization. Done and force-pushed to the same
branch...