From:   Thomas Gleixner <tglx@linutronix.de>
To:     Waiman Long <longman@redhat.com>, Marco Elver <elver@google.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Boqun Feng <boqun.feng@gmail.com>, linux-kernel@vger.kernel.org
Cc:     kasan-dev@googlegroups.com, Mark Rutland <mark.rutland@arm.com>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        Kefeng Wang <wangkefeng.wang@huawei.com>
Subject: Re: [PATCH] locking/mutex: Mark racy reads of owner->on_cpu
In-Reply-To: <2f67a2d9-98d6-eabd-fb5e-4c89574ce52c@redhat.com>
References: <20211202101238.33546-1-elver@google.com>
 <CANpmjNMvPepakONMjTO=FzzeEtvq_CLjPN6=zF35j10rVrJ9Fg@mail.gmail.com>
 <2f67a2d9-98d6-eabd-fb5e-4c89574ce52c@redhat.com>
Date:   Fri, 17 Dec 2021 22:41:51 +0100
Message-ID: <87ee6ac3j4.ffs@tglx>
MIME-Version: 1.0
Content-Type: text/plain
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On Thu, Dec 02 2021 at 10:46, Waiman Long wrote:
> On 12/2/21 06:53, Marco Elver wrote:
> I would like to see owner_on_cpu() extracted out from 
> kernel/locking/rwsem.c into include/linux/sched.h right after 
> vcpu_is_preempted(), for instance, and with READ_ONCE() added. Then it 
> can be used in mutex.c as well. This problem is common to both mutex and 
> rwsem.

And rtmutex.c