linux-kernel - [PATCH v4 2/4] PM / devfreq: Fix kernel warning with cpufreq passive register fail

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Message-Id: <20220614230950.426-3-ansuelsmth@gmail.com>
Date:   Wed, 15 Jun 2022 01:09:48 +0200
From:   Christian 'Ansuel' Marangi <ansuelsmth@...il.com>
To:     MyungJoo Ham <myungjoo.ham@...sung.com>,
        Kyungmin Park <kyungmin.park@...sung.com>,
        Chanwoo Choi <cw00.choi@...sung.com>,
        Sibi Sankar <sibis@...eaurora.org>,
        Saravana Kannan <skannan@...eaurora.org>,
        linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     Christian 'Ansuel' Marangi <ansuelsmth@...il.com>
Subject: [PATCH v4 2/4] PM / devfreq: Fix kernel warning with cpufreq passive register fail

When the cpufreq passive register path from the passive governor fails,
the cpufreq_passive_unregister is called and a kernel WARNING is always
reported.
This is caused by the fact that the devfreq driver already call the
governor unregister with the GOV_STOP, for this reason the second
cpufreq_passive_unregister always return error and a WARN is printed
from the WARN_ON function.
Remove the unregister call from the error handling of the cpufreq register
notifier as it's fundamentally wrong and already handled by the devfreq
core code.

Fixes: a03dacb0316f ("PM / devfreq: Add cpu based scaling support to passive governor")
Signed-off-by: Christian 'Ansuel' Marangi <ansuelsmth@...il.com>
---
 drivers/devfreq/governor_passive.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index 95de336f20d5..dcc9dd518197 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -331,7 +331,6 @@ static int cpufreq_passive_register_notifier(struct devfreq *devfreq)
 err_put_policy:
 	cpufreq_cpu_put(policy);
 err:
-	WARN_ON(cpufreq_passive_unregister_notifier(devfreq));
 
 	return ret;
 }
-- 
2.36.1