lkml.org 
[lkml]   [2020]   [Sep]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 1/5] arch_topology: validate input frequencies to arch_set_freq_scale()
Date
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 <ionela.voinescu@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
---
drivers/base/arch_topology.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
index 75f72d684294..42a08ef693ae 100644
--- a/drivers/base/arch_topology.c
+++ b/drivers/base/arch_topology.c
@@ -33,6 +33,9 @@ void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq,
unsigned long scale;
int i;

+ if (WARN_ON_ONCE(!cur_freq || !max_freq))
+ return;
+
/*
* 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
\
 
 \ /
  Last update: 2020-09-01 22:59    [W:0.096 / U:0.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site