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[71.184.117.43]) by smtp.gmail.com with ESMTPSA id j15sm2026903qtk.48.2020.01.22.09.08.47 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 22 Jan 2020 09:08:47 -0800 (PST) Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable From: Qian Cai Mime-Version: 1.0 (1.0) Subject: Re: [PATCH] locking/osq_lock: fix a data race in osq_wait_next Date: Wed, 22 Jan 2020 12:08:47 -0500 Message-Id: References: <20200122165938.GA16974@willie-the-truck> Cc: mingo@redhat.com, peterz@infradead.org, elver@google.com, linux-kernel@vger.kernel.org In-Reply-To: <20200122165938.GA16974@willie-the-truck> To: Will Deacon X-Mailer: iPhone Mail (17C54) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Jan 22, 2020, at 11:59 AM, Will Deacon wrote: >=20 > I don't understand this; 'next' is a local variable. >=20 > Not keen on the onslaught of random "add a READ_ONCE() to shut the > sanitiser up" patches we're going to get from kcsan :( My fault. I suspect it is node->next. I=E2=80=99ll do a bit more testing to c= onfirm.=