Re: [PATCH v4 1/5] arch_topology: validate input frequencies to arch_set_freq_scale()
From: Viresh Kumar <viresh.kumar@linaro.org>
Date: 2020-08-31 11:25:45
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On 28-08-20, 18:32, Ionela Voinescu wrote:
quoted hunk ↗ jump to hunk
The current frequency passed to arch_set_freq_scale() could end up being 0, signaling an error in setting a new frequency. Also, if the maximum frequency in 0, this will result in a division by 0 error. Therefore, validate these input values before using them for the setting of the frequency scale factor. Signed-off-by: Ionela Voinescu <redacted> Cc: Sudeep Holla <redacted> Cc: Rafael J. Wysocki <redacted> --- drivers/base/arch_topology.c | 5 +++++ 1 file changed, 5 insertions(+)diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c index 75f72d684294..5708eb724790 100644 --- a/drivers/base/arch_topology.c +++ b/drivers/base/arch_topology.c@@ -33,6 +33,11 @@ void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, unsigned long scale; int i; + if (unlikely(!cur_freq || !max_freq)) { + WARN_ON_ONCE(1); + return; + }
This can be written as:
if (WARN_ON_ONCE(!cur_freq || !max_freq))
return;
With that.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
+ /* * If the use of counters for FIE is enabled, just return as we don't * want to update the scale factor with information from CPUFREQ. -- 2.17.1
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