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From:   "Rafael J. Wysocki" <rjw@rjwysocki.net>
To:     Zhenzhong Duan <zhenzhong.duan@oracle.com>
Cc:     linux-kernel@vger.kernel.org, pbonzini@redhat.com,
        rkrcmar@redhat.com, rafael.j.wysocki@intel.com,
        joao.m.martins@oracle.com, mtosatti@redhat.com,
        kvm@vger.kernel.org, linux-pm@vger.kernel.org
Subject: Re: [PATCH RESEND v2 1/4] cpuidle-haltpoll: ensure grow start value is nonzero
Date:   Fri, 15 Nov 2019 11:06:32 +0100
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References: <1573041302-4904-1-git-send-email-zhenzhong.duan@oracle.com> <1573041302-4904-2-git-send-email-zhenzhong.duan@oracle.com>
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On Wednesday, November 6, 2019 12:54:59 PM CET Zhenzhong Duan wrote:
> dev->poll_limit_ns could be zeroed in certain cases (e.g. by
> guest_halt_poll_ns = 0). If guest_halt_poll_grow_start is zero,
> dev->poll_limit_ns will never be bigger than zero.

Given that haltpoll_enable_device() sets dev->poll_limit_ns = 0 to start with,
I don't think that the statement above is correct.