On Thu, 9 May 2024 at 04:39, Christian Brauner brauner@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