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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 4 Jul 2022 13:51:16 -0700
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Subject: Re: [PATCH v4 43/45] namei: initialize parameters passed to step_into()
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Alexander Potapenko <glider@google.com>,
        Alexei Starovoitov <ast@kernel.org>,
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On Mon, Jul 4, 2022 at 1:46 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> Why is that a problem?  It could have been moved to another parent,
> but so it could after we'd crossed to the mounted and we wouldn't have
> noticed (or cared).

Yeah, see my other email.

I agree that it might be a "we don't actually care" situation, where
all we care about that the name was valid at one point (when we picked
up that sequence point). So maybe we don't care about closing it.

But even if so, I think it might warrant a comment, because I still
feel like we're basically "throwing away" our previous sequence point
information without ever checking it.

Maybe all we ever care about is basically "this sequence point
protects the dentry inode pointer for the next lookup", and when it
comes to mount points that ends up being immaterial.

             Linus