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From:   Kees Cook <keescook@chromium.org>
Date:   Thu, 28 Mar 2019 09:52:09 -0700
Message-ID: <CAGXu5j+CFmdPQd_u6=C6ew0Y-j6ihUN7yN1GpJO6V=x2_Q6kRA@mail.gmail.com>
Subject: Re: [PATCH] Convert struct pid count to refcount_t
To:     Joel Fernandes <joel@joelfernandes.org>
Cc:     Jann Horn <jannh@google.com>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Android Kernel Team <kernel-team@android.com>,
        Kernel Hardening <kernel-hardening@lists.openwall.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>,
        Michal Hocko <mhocko@suse.com>,
        Oleg Nesterov <oleg@redhat.com>,
        "Reshetova, Elena" <elena.reshetova@intel.com>
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On Thu, Mar 28, 2019 at 7:37 AM Joel Fernandes <joel@joelfernandes.org> wrote:
> Kees can you describe more the race you had in mind?

I just didn't see any barriers, so it seemed racey to me.

> Also note to the on looker, the original patch I sent is not wrong, that
> still applies and is correct. We are just discussing here any possible issues
> with the *existing* code.

Correct. And akpm has (correctly) taken this for -mm.

-- 
Kees Cook