linux-kernel - [PATCH v1 2/3] cpufreq: Always enforce policy limits even without frequency table

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Message-Id: <20250904032210.92978-3-zhangzihuan@kylinos.cn>
Date: Thu,  4 Sep 2025 11:22:09 +0800
From: Zihuan Zhang <zhangzihuan@...inos.cn>
To: "Rafael J . wysocki" <rafael@...nel.org>,
	Viresh Kumar <viresh.kumar@...aro.org>,
	Saravana Kannan <saravanak@...gle.com>
Cc: zhenglifeng <zhenglifeng1@...wei.com>,
	linux-pm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Zihuan Zhang <zhangzihuan@...inos.cn>
Subject: [PATCH v1 2/3] cpufreq: Always enforce policy limits even without frequency table

Currently, cpufreq_frequency_table_verify() simply returns when the driver’s
frequency table is missing (policy->freq_table == NULL).
This means that cpufreq_verify_within_cpu_limits() is not invoked in such
cases, leaving policy->min and policy->max unchecked.

Some cpufreq drivers handle this manually by calling
cpufreq_verify_within_cpu_limits() even when no frequency table is present,
in order to ensure the policy stays within CPU limits.

To avoid this inconsistency and potential misuse, make
cpufreq_generic_frequency_table_verify() always call
cpufreq_verify_within_cpu_limits(), regardless of whether policy->freq_table
is available. This unifies the behavior across all drivers and makes the helper
safe to use universally.

Signed-off-by: Zihuan Zhang <zhangzihuan@...inos.cn>
---
 drivers/cpufreq/freq_table.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index d5111ee56e38..f4b05dcc479b 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -105,6 +105,7 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
  */
 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy_data *policy)
 {
+	cpufreq_verify_within_cpu_limits(policy);
 	if (!policy->freq_table)
 		return -ENODEV;

-- 
2.25.1