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From:   Qian Cai <cai@lca.pw>
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Subject: Re: [PATCH -next] x86/mm/pat: silence a data race in cpa_4k_install
Date:   Wed, 22 Jan 2020 21:15:07 -0500
Message-Id: <4F7E8467-98F0-483A-BF70-CD06AC78890D@lca.pw>
References: <20200122084604.GP14914@hirez.programming.kicks-ass.net>
Cc:     Borislav Petkov <bp@alien8.de>, Marco Elver <elver@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Andy Lutomirski <luto@kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
In-Reply-To: <20200122084604.GP14914@hirez.programming.kicks-ass.net>
To:     Peter Zijlstra <peterz@infradead.org>
Sender: linux-kernel-owner@vger.kernel.org
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> On Jan 22, 2020, at 3:46 AM, Peter Zijlstra <peterz@infradead.org> wrote:
>=20
> Documentation. It is a clear and concise marker of intent. Unintended
> data races are bad.
>=20
> Also, we've been adding annotations to the kernel source forever,
> sparse, lockdep, etc.. now KCSAN. All we have to do is make sure they're
> minimally invasive, and in that regard the date_race() marker is spot on
> IMO.

Okay, so which way should we move forward with this then? Borislav liked __n=
o_kasan_or_inline and Peter liked data_race(). I personally like data_race()=
 more because it has nothing to do with the GCC bug, but I realized my opini=
on has little weight here.=