Re: [PATCH v2] fs: handle shrinker registration failure in sget_userns

[Michal Hocko]

On Thu 23-11-17 14:55:40, Al Viro wrote:
> On Thu, Nov 23, 2017 at 03:35:37PM +0100, Michal Hocko wrote:
> > Hopefully less screwed version.  But as I've said I am not really
> > familiar with the code and do not feel competent to change it so please
> > be very careful here. I've moved the shrinker registration to
> > alloc_super which turned out to be simpler.
> 
> I don't get it.  Why the hell do we need all that PITA in the first place?
> Just make sget_userns() end with
> 	if (unlikely(regsiter_shrinker(&s->s_shrink) != 0)) {
> 		deactivate_locked_super(s);
> 		s = ERR_PTR(-ENOMEM);
> 	}
> 	return s;
> and be done with that.  All there is to it...

Who is going to unregister that shrinker on other failure paths?

-- 
Michal Hocko
SUSE Labs