On Wed, Aug 14, 2024 at 03:18:17AM +0100, Al Viro wrote: > That's not the only problem; your "is it negative" test is inherently > racy in RCU mode. IOW, what is positive at the time you get here can > bloody well go negative immediately afterwards. Hit that with > O_CREAT and you've got a bogus ENOENT... Hmm... OTOH, in that case you end up in step_into(), which will do the right thing... How well does that series survive NFS client regression tests? That's where I'd expect potentially subtle shite, what with short-circuited ->d_revalidate() on the final pathwalk step in open()...
