[PATCH] cpufreq: CPPC: Avoid overflow when calculating desired_perf

From	Hoan Tran <hotran@apm.com>
Newsgroups	linux.kernel
Subject	[PATCH] cpufreq: CPPC: Avoid overflow when calculating desired_perf
Date	2016-09-15 01:10 +0200
Message-ID	<shrtw-7hp-27@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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This patch fixes overflow issue when calculating the desired_perf.

Signed-off-by: Hoan Tran <hotran@apm.com>
---
 drivers/cpufreq/cppc_cpufreq.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index 894e465..3e0961e 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -84,7 +84,8 @@ static int cppc_cpufreq_set_target(struct cpufreq_policy *policy,
 
 	cpu = all_cpu_data[policy->cpu];
 
-	cpu->perf_ctrls.desired_perf = target_freq * policy->max / cppc_dmi_max_khz;
+	cpu->perf_ctrls.desired_perf =
+		(u64)target_freq * policy->max / cppc_dmi_max_khz;
 	freqs.old = policy->cur;
 	freqs.new = target_freq;
 
-- 
1.9.1

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[PATCH] cpufreq: CPPC: Avoid overflow when calculating desired_perf Hoan Tran <hotran@apm.com> - 2016-09-15 01:10 +0200
  Re: [PATCH] cpufreq: CPPC: Avoid overflow when calculating desired_perf "Rafael J. Wysocki" <rjw@rjwysocki.net> - 2016-09-15 02:50 +0200
    Re: [PATCH] cpufreq: CPPC: Avoid overflow when calculating desired_perf Hoan Tran <hotran@apm.com> - 2016-09-15 05:10 +0200
      Re: [PATCH] cpufreq: CPPC: Avoid overflow when calculating  desired_perf Al Stone <ahs3@redhat.com> - 2016-09-19 21:00 +0200

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