Re: [git pull] vfs.git spurious ENOTDIR fix

[Linus Torvalds <torvalds@linux-foundation.org>]

On Sat, Aug 1, 2015 at 5:23 PM, Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> Branch head should be at 97242f9, just to make sure you get
> the right one...

Ok, merged in my tree.

However, looking at this, I'm struck by how all the callers of
"link_path_walk()" tend to have very similar patterns wrt error
handling.

And I'm wondering - wouldn't it be nicer to extend that pattern a bit
more, and make the *callers* of link_path_walk() all do

        if (error) {
                if (nd->flags & LOOKUP_RCU) {
                        if (unlazy_walk(nd, NULL, 0))
                                error = -ECHILD;
                }
        }

and maybe even make that part of terminate_walk() that everybody calls
after getting here.

Because it's not just that "!d_can_lookup()" case that triggers it,
you also have that pattern in the RCU error case for may_lookup(), and
get_link().

So why don't we make the rule that *every* single error we get during
an RCU walk should do that unlazy_walk() and turn the error into
ECHILD on failure. Hmm? We're almost there as-is.

             Linus