Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in ->exit()

From	"Rafael J. Wysocki" <rafael@kernel.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in ->exit()
Date	2016-03-30 13:20 +0200
Message-ID	<rimkh-4wo-1@gated-at.bofh.it> (permalink)
References	<rifVw-5u-11@gated-at.bofh.it> <rimkh-4wo-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Wed, Mar 30, 2016 at 1:15 PM, Rafael J. Wysocki <rafael@kernel.org> wrote:
> On Wed, Mar 30, 2016 at 6:24 AM, Viresh Kumar <viresh.kumar@linaro.org> wrote:
>> Its always set by ->init() and so it will always be there in ->exit().
>> There is no need to have a special check for just that.
>
> I'm not sure what happens if there are two (or more) CPUs in the policy, though.
>
> That case is almost certainly handled incorrectly here (or rather not
> handled at all), but it may just happen to sort of work, because the
> first exiting CPU will clear driver_data and the second one will
> notice that it is NULL now.  Of course, that still is racy with
> respect to governors etc, but I'd rather fix the driver properly.

Sorry, scratch that.  To core only calls ->exit for the last CPU in
the policy, so I agree with the patch.

It conflicts with other stuff (as you know), so I'm not sure about the
order in which they are going to be applied, though.

Thanks,
Rafael

Thread

[PATCH] cpufreq: acpi: policy->driver_data can't be NULL in ->exit() Viresh Kumar <viresh.kumar@linaro.org> - 2016-03-30 06:30 +0200
  Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in ->exit() "Rafael J. Wysocki" <rafael@kernel.org> - 2016-03-30 13:20 +0200
    Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in  ->exit() Viresh Kumar <viresh.kumar@linaro.org> - 2016-03-30 13:30 +0200
    Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in  ->exit() Viresh Kumar <viresh.kumar@linaro.org> - 2016-04-01 10:30 +0200
      Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in ->exit() "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2016-04-01 23:00 +0200
  Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in ->exit() "Rafael J. Wysocki" <rafael@kernel.org> - 2016-03-30 13:20 +0200
    Re: [PATCH] cpufreq: acpi: policy->driver_data can't be NULL in  ->exit() Viresh Kumar <viresh.kumar@linaro.org> - 2016-03-30 13:30 +0200

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