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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 18 Jul 2018 16:06:48 -0700
Message-ID: <CA+55aFyJJSf0M8ij+Mzea7sFWOuDNcC4eA5KyVYeiKv8HY6LvA@mail.gmail.com>
Subject: Re: [RFC] call_with_creds()
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Miklos Szeredi <mszeredi@redhat.com>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Wed, Jul 18, 2018 at 2:22 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> Why is counter any better than LSB of a pointer?

Easier nesting, but if you do it with the "surround by a macro" model
I guess you can just save/restore instead (like you did in
call_with_creds).

           Linus