From mboxrd@z Thu Jan  1 00:00:00 1970
From: Florian Weimer <fweimer@redhat.com>
Subject: Re: [PATCH v2 1/5] fs: Add support for an O_MAYEXEC flag on sys_open()
Date: Fri, 06 Sep 2019 20:44:03 +0200
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        Layton's message of "Fri, 06 Sep 2019 14:38:11 -0400")
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* Jeff Layton:

> Even better would be to declare the new flag in some openat2-only flag
> space, so there's no confusion about it being supported by legacy open
> calls.

Isn't that desirable anyway because otherwise fcntl with F_GETFL will
give really confusing results?

> If glibc wants to implement an open -> openat2 wrapper in userland
> later, it can set that flag in the wrapper implicitly to emulate the old
> behavior.

I see us rather doing the opposite, i.e. implement openat2 with
non-exotic flags using openat.  But we've bitten by this in the past, so
maybe that's not such a great idea.  It's tempting to make the same
mistake again for every new system call.

Thanks,
Florian