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[CPUFREQ] Fix ondemand to not request targets outside policy limits 

Dominik said:
target_freq cannot be below policy->min or above policy->max.
If it were, the whole cpufreq subsystem is broken.

But (answer):
I think the "ondemand" governor can ask for a target frequency that is
below policy->min.
...
A patch such as below may be needed to sanitize the target frequency
requested by "ondemand". The "conservative" governor already has this check:

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Dave Jones <davej@redhat.com>

# diff -bur x/drivers/cpufreq/cpufreq_ondemand.c.orig y/drivers/cpufreq/cpufreq_ondemand.c
This commit is contained in:
Nagananda.Chumbalkar@hp.com 2009-12-21 23:40:52 +01:00 committed by Dave Jones
parent 557a701c16
commit 1dbf58881f
1 changed files with 3 additions and 0 deletions
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3
drivers/cpufreq/cpufreq_ondemand.c
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@ -554,6 +554,9 @@ static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
(dbs_tuners_ins.up_threshold - (dbs_tuners_ins.up_threshold -
dbs_tuners_ins.down_differential); dbs_tuners_ins.down_differential);
if (freq_next < policy->min)
freq_next = policy->min;
if (!dbs_tuners_ins.powersave_bias) { if (!dbs_tuners_ins.powersave_bias) {
__cpufreq_driver_target(policy, freq_next, __cpufreq_driver_target(policy, freq_next,
CPUFREQ_RELATION_L); CPUFREQ_RELATION_L);