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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     Hillf Danton <hdanton@sina.com>,
        Paolo Bonzini <pbonzini@redhat.com>
Cc:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        "Michael S. Tsirkin" <mst@redhat.com>, linux-mm@kvack.org,
        LKML <linux-kernel@vger.kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>
Subject: Re: 5.13-rt1 + KVM = WARNING: at fs/eventfd.c:74 eventfd_signal()
In-Reply-To: <20210721070452.1008-1-hdanton@sina.com>
References: <df278db6-1fc0-3d42-9c0e-f5a085c6351e@redhat.com> <8dfc0ee9-b97a-8ca8-d057-31c8cad3f5b6@redhat.com> <f0254740-944d-201b-9a66-9db1fe480ca6@redhat.com> <475f84e2-78ee-1a24-ef57-b16c1f2651ed@redhat.com> <20210715102249.2205-1-hdanton@sina.com> <20210716020611.2288-1-hdanton@sina.com> <20210716075539.2376-1-hdanton@sina.com> <20210716093725.2438-1-hdanton@sina.com> <20210718124219.1521-1-hdanton@sina.com> <20210721070452.1008-1-hdanton@sina.com>
Date:   Wed, 21 Jul 2021 09:25:32 +0200
Message-ID: <87im14cemr.ffs@nanos.tec.linutronix.de>
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On Wed, Jul 21 2021 at 15:04, Hillf Danton wrote:
>
> But the preempting waker can not make sense without the waiter who is bloody
> special. Why is it so in the first place? Or it is not at all but the race
> existing from Monday to Friday.

See the large comment in eventfd_poll().