Re: [PATCH v1 3/3] cpufreq: Rearrange locking in cpufreq_remove_dev()

From: Viresh Kumar <viresh.kumar@linaro.org>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Linux PM <linux-pm@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1 3/3] cpufreq: Rearrange locking in cpufreq_remove_dev()
Date: Thu, 12 May 2022 13:12:36 +0530	[thread overview]
Message-ID: <20220512074236.bkamv2o5hgson243@vireshk-i7> (raw)
In-Reply-To: <1836239.tdWV9SEqCh@kreacher>

On 11-05-22, 17:51, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> Currently, cpufreq_remove_dev() invokes the ->exit() driver callback
> without holding the policy rwsem which is inconsistent with what
> happens if ->exit() is invoked directly from cpufreq_offline().
> 
> It also manipulates the real_cpus mask and removes the CPU device
> symlink without holding the policy rwsem, but cpufreq_offline() holds
> the rwsem around the modifications thereof.
> 
> For consistency, modify cpufreq_remove_dev() to hold the policy rwsem
> until the ->exit() callback has been called (or it has been determined
> that it is not necessary to call it).
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> ---
>  drivers/cpufreq/cpufreq.c |   21 ++++++++++++++-------
>  1 file changed, 14 insertions(+), 7 deletions(-)

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

-- 
viresh