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From:   David Howells <dhowells@redhat.com>
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To:     Kees Cook <keescook@chromium.org>
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        Peter Zijlstra <peterz@infradead.org>,
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Subject: Re: [PATCH 0/3] Convert nsproxy, groups, and creds to refcount_t
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Date:   Tue, 28 Jul 2020 12:01:51 +0100
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Kees Cook <keescook@chromium.org> wrote:

> > I've been gradually undoing some of the conversions as there's no equi=
valent
> > of atomic_add_return() and atomic_dec_return() that allow me to log th=
e
> > altered refcount through a tracepoint.
> =

> Please do not _undo_ the changes; just add the API you need.

And _please_ do not convert atomic_inc/dec_return() into refcount_read() +
refcount_xxx().  They are _not_ equivalent.

David