[Linaro-mm-sig] Re: [PATCH] epoll: try to be a _bit_ better about file lifetimes

[Linus Torvalds]

On Thu, 9 May 2024 at 04:39, Christian Brauner <brauner at kernel.org> wrote:
>
> Not worth it without someone explaining in detail why imho. First pass
> should be to try and replace kcmp() in scenarios where it's obviously
> not needed or overkill.

Ack.

> I've added a CLASS(fd_raw) in a preliminary patch since we'll need that
> anyway which means that your comparison patch becomes even simpler imho.
> I've also added a selftest patch:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git/log/?h=vfs.misc

LGTM.

Maybe worth adding an explicit test for "open same file, but two
separate opens, F_DUPFD_QUERY returns 0? Just to clarify the "it's not
testing the file on the filesystem for equality, but the file pointer
itself".

             Linus