Hi Rafael,

Thanks for reviewing the change.

On 2/23/2024 12:52 AM, Rafael J. Wysocki wrote:

On Thu, Feb 22, 2024 at 9:35 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.

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

---

include/linux/cpufreq.h | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index afda5f24d3dd..42d98b576a36 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_table_index_is_in_limits(struct cpufreq_policy *policy,

•                                               int idx)
  

This is not really about the index only, but about the frequency at that index too, so I'd call the function differently.

ACK

...

+{

•   unsigned int freq;
  

•   if (idx < 0)
  

•           return false;
  

•   freq = policy->freq_table[idx].frequency;
  

•   return (freq == clamp_val(freq, policy->min, policy->max));
  

Redundant outer parens.

ACK

...

+}

• static inline int cpufreq_frequency_table_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation)

@@ -1054,7 +1067,10 @@ 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
  

•    */
  

This comment need not be multi-line.

ACK I will make the changes in next patch set.

Thanks Shivnandan

...

•   if (!cpufreq_table_index_is_in_limits(policy, idx) && efficiencies) {
             efficiencies = false;
             goto retry;
     }
  

--

Thanks!