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Date:   Mon, 27 Jun 2022 08:43:14 -0400
From:   Qian Cai <quic_qiancai@quicinc.com>
To:     Miaohe Lin <linmiaohe@huawei.com>
CC:     <akpm@linux-foundation.org>, <david@redhat.com>,
        <ying.huang@intel.com>, <songmuchun@bytedance.com>,
        <linux-mm@kvack.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v3 1/2] mm/swapfile: fix possible data races of
 inuse_pages
Message-ID: <Yrml4mB3sa5fZVJa@qian>
References: <20220625093346.48894-1-linmiaohe@huawei.com>
 <20220625093346.48894-2-linmiaohe@huawei.com>
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On Sat, Jun 25, 2022 at 05:33:45PM +0800, Miaohe Lin wrote:
> si->inuse_pages could still be accessed concurrently now. The plain reads
> outside si->lock critical section, i.e. swap_show and si_swapinfo, which
> results in data races. READ_ONCE and WRITE_ONCE is used to fix such data
> races. Note these data races should be ok because they're just used for
> showing swap info.

Was this found by kcsan? If so, it would be useful to record the exact
kscan report in the commit message.