Message-ID: <2cb7ef5c-6714-254c-0308-f72f53a6612a@huawei.com>
Date:   Thu, 2 Dec 2021 19:44:31 +0800
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Subject: Re: [PATCH v2] arm64: Enable KCSAN
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To:     Marco Elver <elver@google.com>
CC:     Mark Rutland <mark.rutland@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <joey.gouly@arm.com>
References: <20211129145732.27000-1-wangkefeng.wang@huawei.com>
 <YadiUPpJ0gADbiHQ@FVFF77S0Q05N>
 <811af0bc-0c99-37f6-a39a-095418b10661@huawei.com>
 <Yaic31SbYFJ4zAl0@elver.google.com>
 <b641f1ea-6def-0fe4-d273-03c35c4aa7d6@huawei.com>
 <CANpmjNOOVQjoczanQndUoDRMCOfV4FB6bnezEjskKh3iDzaQVg@mail.gmail.com>
From:   Kefeng Wang <wangkefeng.wang@huawei.com>
In-Reply-To: <CANpmjNOOVQjoczanQndUoDRMCOfV4FB6bnezEjskKh3iDzaQVg@mail.gmail.com>
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On 2021/12/2 18:58, Marco Elver wrote:
> On Thu, 2 Dec 2021 at 11:45, Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
> [...]
>>>> for now and more explanation into changlog.
>>> So what I gather arm64's final select line may look like:
>>>
>>>        select HAVE_ARCH_KCSAN if EXPERT && (CC_IS_GCC || CLANG_VERSION >= 120000)
>> Yes,  that's what we want now.
> I think we have all the pieces sorted out, so hopefully you have
> everything you need to do v3.
OK, I will resend v3.
>
> [...]
>>> I actually have a "fix" for the data race in rwsem_spin_on_owner, that
>>> also shows where the other racing access comes from... which reminds me:
>>> https://lkml.kernel.org/r/20211202101238.33546-1-elver@google.com
>> There's a owner_on_cpu(),  we could reuse it,
> That looks like a reasonable thing to do, but can't say if it is
> actually the right thing to do. You could suggest it in reply to the
> patch I just sent and see what people say.
Could you cc me, I can't reply email due to no subscribe to mailing 
list, thanks.