From 39a8e540c41812709ba9ce791a9d5e2fc49e1932 Mon Sep 17 00:00:00 2001 From: Shivnandan Kumar Date: Tue, 27 Feb 2024 14:43:51 +0530 Subject: [PATCH] cpufreq: Limit resolving a frequency to policy min/max [ Upstream commit d394abcb12bb1a6f309c1221fdb8e73594ecf1b4 ] Resolving a frequency to an efficient one should not transgress policy->max (which can be set for thermal reason) and policy->min. Currently, there is possibility where scaling_cur_freq can exceed scaling_max_freq when scaling_max_freq is an inefficient frequency. Add a check to ensure that resolving a frequency will respect policy->min/max. Cc: All applicable Fixes: 1f39fa0dccff ("cpufreq: Introducing CPUFREQ_RELATION_E") Signed-off-by: Shivnandan Kumar [ rjw: Whitespace adjustment, changelog edits ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- include/linux/cpufreq.h | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index afda5f24d3dd..320fab7d2e94 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -1021,6 +1021,18 @@ static inline int cpufreq_table_find_index_c(struct cpufreq_policy *policy, efficiencies); } +static inline bool cpufreq_is_in_limits(struct cpufreq_policy *policy, int idx) +{ + unsigned int freq; + + if (idx < 0) + return false; + + freq = policy->freq_table[idx].frequency; + + return freq == clamp_val(freq, policy->min, policy->max); +} + static inline int cpufreq_frequency_table_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) @@ -1054,7 +1066,8 @@ static inline int cpufreq_frequency_table_target(struct cpufreq_policy *policy, return 0; } - if (idx < 0 && efficiencies) { + /* Limit frequency index to honor policy->min/max */ + if (!cpufreq_is_in_limits(policy, idx) && efficiencies) { efficiencies = false; goto retry; }