linux-kernel - [PATCH 4.15 71/72] Revert "cpufreq: Fix governor module removal race"

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Date:   Fri,  6 Apr 2018 15:24:46 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Ben Hutchings <ben.hutchings@...ethink.co.uk>,
        "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        Viresh Kumar <viresh.kumar@...aro.org>,
        Sasha Levin <alexander.levin@...rosoft.com>
Subject: [PATCH 4.15 71/72] Revert "cpufreq: Fix governor module removal race"

4.15-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

This reverts commit a853301f77b5c4feb5e17aebfd92018269525523 which was
commit a8b149d32b663c1a4105273295184b78f53d33cf upstream.

The backport was not correct, so just drop it entirely.

Reported-by: Ben Hutchings <ben.hutchings@...ethink.co.uk>
Cc: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
Cc: Viresh Kumar <viresh.kumar@...aro.org>
Cc: Sasha Levin <alexander.levin@...rosoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/cpufreq/cpufreq.c |    6 ------
 1 file changed, 6 deletions(-)

--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -637,8 +637,6 @@ static int cpufreq_parse_governor(char *
 			*governor = t;
 			err = 0;
 		}
-		if (t && !try_module_get(t->owner))
-			t = NULL;
 
 		mutex_unlock(&cpufreq_governor_mutex);
 	}
@@ -767,10 +765,6 @@ static ssize_t store_scaling_governor(st
 		return -EINVAL;
 
 	ret = cpufreq_set_policy(policy, &new_policy);
-
-	if (new_policy.governor)
-		module_put(new_policy.governor->owner);
-
 	return ret ? ret : count;
 }