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From: Jagadeesh Kona <quic_jkona@quicinc.com>
To: Sudeep Holla <sudeep.holla@arm.com>,
        Viresh Kumar
	<viresh.kumar@linaro.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        "Cristian Marussi" <cristian.marussi@arm.com>
CC: <linux-arm-kernel@lists.infradead.org>, <linux-pm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, Taniya Das <quic_tdas@quicinc.com>,
        "Ajit
 Pandey" <quic_ajipan@quicinc.com>,
        Imran Shaik <quic_imrashai@quicinc.com>,
        Vivek Aknurwar <quic_viveka@quicinc.com>,
        Mike Tipton
	<quic_mdtipton@quicinc.com>,
        Jagadeesh Kona <quic_jkona@quicinc.com>
Subject: [PATCH V2] cpufreq: scmi: Avoid overflow of target_freq in fast switch
Date: Mon, 20 May 2024 12:07:32 +0530
Message-ID: <20240520063732.11220-1-quic_jkona@quicinc.com>
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Conversion of target_freq to HZ in scmi_cpufreq_fast_switch()
can lead to overflow if the multiplied result is greater than
UINT_MAX, since type of target_freq is unsigned int. Avoid this
overflow by assigning target_freq to unsigned long variable for
converting it to HZ.

Signed-off-by: Jagadeesh Kona <quic_jkona@quicinc.com>
---
Changes in V2:
  - Updated freq variable from u64 to unsigned long to keep it
    consistent with the rate parameter in scmi .freq_set() callback
  - Link to v1: https://lore.kernel.org/all/20240517070157.19553-1-quic_jkona@quicinc.com/
---
 drivers/cpufreq/scmi-cpufreq.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c
index 3b4f6bfb2f4c..b87fd127aa43 100644
--- a/drivers/cpufreq/scmi-cpufreq.c
+++ b/drivers/cpufreq/scmi-cpufreq.c
@@ -63,9 +63,9 @@ static unsigned int scmi_cpufreq_fast_switch(struct cpufreq_policy *policy,
 					     unsigned int target_freq)
 {
 	struct scmi_data *priv = policy->driver_data;
+	unsigned long freq = target_freq;
 
-	if (!perf_ops->freq_set(ph, priv->domain_id,
-				target_freq * 1000, true))
+	if (!perf_ops->freq_set(ph, priv->domain_id, freq * 1000, true))
 		return target_freq;
 
 	return 0;
-- 
2.43.0