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Date:   Fri, 31 May 2019 15:35:36 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Jann Horn <jannh@google.com>
Cc:     "Eric W . Biederman" <ebiederm@xmission.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kees Cook <keescook@chromium.org>,
        David Howells <dhowells@redhat.com>,
        kernel list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] ptrace: restore smp_rmb() in __ptrace_may_access()
Message-ID: <20190531133535.GB31323@redhat.com>
References: <20190529113157.227380-1-jannh@google.com>
 <20190530123452.GF22536@redhat.com>
 <CAG48ez0ivQ+gfwKMife-3ZwBuqAuc1BhDGW3dtYTHMq0sByuNw@mail.gmail.com>
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On 05/31, Jann Horn wrote:
>
> So I guess I should make a v2 that still adds the smp_rmb() in
> __ptrace_may_access(), but gets rid of the smp_wmb() in
> commit_creds()? (With a comment above the rcu_assign_pointer() that
> explains the ordering?)

I am fine either way, whatever you like more.

If you prefer v1 (this patch), feel free to add

Acked-by: Oleg Nesterov <oleg@redhat.com>