diff options
| author | Chen Yu <yu.c.chen@intel.com> | 2015-09-09 18:27:31 +0800 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2015-09-09 22:55:23 +0200 |
| commit | 43717aadd2bc87fb10fbf1cd815c1cbae9bb95b3 (patch) | |
| tree | a525f784c4a857f55c09d6dc8eee594ea042cffb /drivers/cpufreq | |
| parent | 953ba9ff77f3d08635712eaeffb218d46889b58a (diff) | |
| download | linux-43717aadd2bc87fb10fbf1cd815c1cbae9bb95b3.tar.bz2 | |
intel_pstate: Fix user input of min/max to legal policy region
In current code, max_perf_pct might be smaller than min_perf_pct
by improper user input:
$ grep . /sys/devices/system/cpu/intel_pstate/m*_perf_pct
/sys/devices/system/cpu/intel_pstate/max_perf_pct:100
/sys/devices/system/cpu/intel_pstate/min_perf_pct:100
$ echo 80 > /sys/devices/system/cpu/intel_pstate/max_perf_pct
$ grep . /sys/devices/system/cpu/intel_pstate/m*_perf_pct
/sys/devices/system/cpu/intel_pstate/max_perf_pct:80
/sys/devices/system/cpu/intel_pstate/min_perf_pct:100
Fix this problem by 2 steps:
1. Normalize the user input to [min_policy, max_policy].
2. Make sure max_perf_pct>=min_perf_pct, suggested by Seiichi Ikarashi.
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Acked-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/intel_pstate.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 31d0548638e8..63075cc4a476 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -423,6 +423,8 @@ static ssize_t store_max_perf_pct(struct kobject *a, struct attribute *b, limits.max_sysfs_pct = clamp_t(int, input, 0 , 100); limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct); + limits.max_perf_pct = max(limits.min_policy_pct, limits.max_perf_pct); + limits.max_perf_pct = max(limits.min_perf_pct, limits.max_perf_pct); limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100)); if (hwp_active) @@ -442,6 +444,8 @@ static ssize_t store_min_perf_pct(struct kobject *a, struct attribute *b, limits.min_sysfs_pct = clamp_t(int, input, 0 , 100); limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct); + limits.min_perf_pct = min(limits.max_policy_pct, limits.min_perf_pct); + limits.min_perf_pct = min(limits.max_perf_pct, limits.min_perf_pct); limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); if (hwp_active) @@ -989,12 +993,19 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) limits.min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq; limits.min_policy_pct = clamp_t(int, limits.min_policy_pct, 0 , 100); - limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct); - limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); - limits.max_policy_pct = (policy->max * 100) / policy->cpuinfo.max_freq; limits.max_policy_pct = clamp_t(int, limits.max_policy_pct, 0 , 100); + + /* Normalize user input to [min_policy_pct, max_policy_pct] */ + limits.min_perf_pct = max(limits.min_policy_pct, limits.min_sysfs_pct); + limits.min_perf_pct = min(limits.max_policy_pct, limits.min_perf_pct); limits.max_perf_pct = min(limits.max_policy_pct, limits.max_sysfs_pct); + limits.max_perf_pct = max(limits.min_policy_pct, limits.max_perf_pct); + + /* Make sure min_perf_pct <= max_perf_pct */ + limits.min_perf_pct = min(limits.max_perf_pct, limits.min_perf_pct); + + limits.min_perf = div_fp(int_tofp(limits.min_perf_pct), int_tofp(100)); limits.max_perf = div_fp(int_tofp(limits.max_perf_pct), int_tofp(100)); if (hwp_active) |