On Tue, Feb 27, 2024 at 10:15 AM Shivnandan Kumar quic_kshivnan@quicinc.com wrote:

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 inefficient frequency. Add additional check to ensure that resolving a frequency will respect policy->min/max.

Cc: stable@vger.kernel.org Fixes: 1f39fa0dccff ("cpufreq: Introducing CPUFREQ_RELATION_E") Signed-off-by: Shivnandan Kumar quic_kshivnan@quicinc.com --

Changes in v2: -rename function name from cpufreq_table_index_is_in_limits to cpufreq_is_in_limits -remove redundant outer parenthesis in return statement -Make comment single line

--

include/linux/cpufreq.h | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index afda5f24d3dd..7741244dee6e 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -1021,6 +1021,19 @@ 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 +1067,8 @@ 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;
    }
  

--

Applied (with a whitespace adjustment and changelog edits) as 6.9 material, thanks!