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Date: Mon, 10 Nov 2014 06:12:35 -0800
From: Guenter Roeck <linux@roeck-us.net>
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To: Pavel Machek <pavel@ucw.cz>
CC: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
        Alan Cox <gnomes@lxorguk.ukuu.org.uk>, Alexander Graf <agraf@suse.de>,
        Andrew Morton <akpm@linux-foundation.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Heiko Stuebner <heiko@sntech.de>, Lee Jones <lee.jones@linaro.org>,
        Len Brown <len.brown@intel.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Romain Perier <romain.perier@gmail.com>
Subject: Re: [PATCH v6 00/48] kernel: Add support for power-off handler call
 chain
References: <1415583785-6980-1-git-send-email-linux@roeck-us.net> <20141110083347.GA29543@amd>
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On 11/10/2014 12:33 AM, Pavel Machek wrote:
> Hi!
>
>> Introduce a system power-off handler call chain to solve the described
>> problems.  This call chain is expected to be executed from the architecture
>> specific machine_power_off() function.  Drivers providing system power-off
>> functionality are expected to register with this call chain.  By using the
>> priority field in the notifier block, callers can control power-off
>> handler
>
> Linus rather disliked the idea of notifier chains for this... And I
> don't see how it got addressed.
>
As I understand, Linus primarily disliked the idea of callbacks, which is
what the code does, only with no order or protection against race conditions.

Frankly I have no idea how to solve the power-off problem without callbacks.
If you have one, please let me know.

Guenter