Merge tag 'pm-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management fixes from Rafael Wysocki:
 "These fix CPU base frequency reporting in the intel_pstate driver and
  a use-after-free in the scpi-cpufreq driver.

  Specifics:

   - Fix the ACPI CPPC library to actually follow the specification when
     decoding the guaranteed performance register information and make
     the intel_pstate driver to fall back to the nominal frequency when
     reporting the base frequency if the guaranteed performance register
     information is not there (Srinivas Pandruvada).

   - Fix use-after-free in the exit callback of the scpi-cpufreq left
     after an update during the 5.0 development cycle (Vincent Stehlé)"

* tag 'pm-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpufreq: scpi: Fix use after free
  cpufreq: intel_pstate: Also use CPPC nominal_perf for base_frequency
  ACPI / CPPC: Fix guaranteed performance handling

3 files changed, 12 insertions, 4 deletions

diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index 1b207fca1420..d4244e7d0e38 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -1150,8 +1150,13 @@ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps)
         cpc_read(cpunum, nominal_reg, &nom);
         perf_caps->nominal_perf = nom;
 
-        cpc_read(cpunum, guaranteed_reg, &guaranteed);
-        perf_caps->guaranteed_perf = guaranteed;
+        if (guaranteed_reg->type != ACPI_TYPE_BUFFER  ||
+            IS_NULL_REG(&guaranteed_reg->cpc_entry.reg)) {
+                perf_caps->guaranteed_perf = 0;
+        } else {
+                cpc_read(cpunum, guaranteed_reg, &guaranteed);
+                perf_caps->guaranteed_perf = guaranteed;
+        }
 
         cpc_read(cpunum, lowest_non_linear_reg, &min_nonlinear);
         perf_caps->lowest_nonlinear_perf = min_nonlinear;
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index e22f0dbaebb1..b599c7318aab 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -385,7 +385,10 @@ static int intel_pstate_get_cppc_guranteed(int cpu)
         if (ret)
                 return ret;
 
-        return cppc_perf.guaranteed_perf;
+        if (cppc_perf.guaranteed_perf)
+                return cppc_perf.guaranteed_perf;
+
+        return cppc_perf.nominal_perf;
 }
 
 #else /* CONFIG_ACPI_CPPC_LIB */
diff --git a/drivers/cpufreq/scpi-cpufreq.c b/drivers/cpufreq/scpi-cpufreq.c
index 3f49427766b8..2b51e0718c9f 100644
--- a/drivers/cpufreq/scpi-cpufreq.c
+++ b/drivers/cpufreq/scpi-cpufreq.c
@@ -189,8 +189,8 @@ static int scpi_cpufreq_exit(struct cpufreq_policy *policy)
 
         clk_put(priv->clk);
         dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
-        kfree(priv);
         dev_pm_opp_remove_all_dynamic(priv->cpu_dev);
+        kfree(priv);
 
         return 0;
 }