Merge tag 'pm-5.14-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "These include cpufreq core simplifications and fixes, cpufreq driver
  updates, cpuidle driver update, a generic power domains (genpd)
  locking fix and a debug-related simplification of the PM core.

  Specifics:

   - Drop the ->stop_cpu() (not really useful) and ->resolve_freq()
     (unused) cpufreq driver callbacks and modify the users of the
     former accordingly (Viresh Kumar, Rafael Wysocki).

   - Add frequency invariance support to the ACPI CPPC cpufreq driver
     again along with the related fixes and cleanups (Viresh Kumar).

   - Update the Meditak, qcom and SCMI ARM cpufreq drivers (Fabien
     Parent, Seiya Wang, Sibi Sankar, Christophe JAILLET).

   - Rename black/white-lists in the DT cpufreq driver (Viresh Kumar).

   - Add generic performance domains support to the dvfs DT bindings
     (Sudeep Holla).

   - Refine locking in the generic power domains (genpd) support code to
     avoid lock dependency issues (Stephen Boyd).

   - Update the MSM and qcom ARM cpuidle drivers (Bartosz Dudziak).

   - Simplify the PM core debug code by using ktime_us_delta() to
     compute time interval lengths (Mark-PK Tsai)"

* tag 'pm-5.14-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (21 commits)
  PM: domains: Shrink locking area of the gpd_list_lock
  PM: sleep: Use ktime_us_delta() in initcall_debug_report()
  cpufreq: CPPC: Add support for frequency invariance
  arch_topology: Avoid use-after-free for scale_freq_data
  cpufreq: CPPC: Pass structure instance by reference
  cpufreq: CPPC: Fix potential memleak in cppc_cpufreq_cpu_init
  cpufreq: Remove ->resolve_freq()
  cpufreq: Reuse cpufreq_driver_resolve_freq() in __cpufreq_driver_target()
  cpufreq: Remove the ->stop_cpu() driver callback
  cpufreq: powernv: Migrate to ->exit() callback instead of ->stop_cpu()
  cpufreq: CPPC: Migrate to ->exit() callback instead of ->stop_cpu()
  cpufreq: intel_pstate: Combine ->stop_cpu() and ->offline()
  cpuidle: qcom: Add SPM register data for MSM8226
  dt-bindings: arm: msm: Add SAW2 for MSM8226
  dt-bindings: cpufreq: update cpu type and clock name for MT8173 SoC
  clk: mediatek: remove deprecated CLK_INFRA_CA57SEL for MT8173 SoC
  cpufreq: dt: Rename black/white-lists
  cpufreq: scmi: Fix an error message
  cpufreq: mediatek: add support for mt8365
  dt-bindings: dvfs: Add support for generic performance domains
  ...

3 files changed, 39 insertions, 31 deletions

diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
index c1179edc0f3b..921312a8d957 100644
--- a/drivers/base/arch_topology.c
+++ b/drivers/base/arch_topology.c
@@ -18,10 +18,11 @@
 #include <linux/cpumask.h>
 #include <linux/init.h>
 #include <linux/percpu.h>
+#include <linux/rcupdate.h>
 #include <linux/sched.h>
 #include <linux/smp.h>
 
-static DEFINE_PER_CPU(struct scale_freq_data *, sft_data);
+static DEFINE_PER_CPU(struct scale_freq_data __rcu *, sft_data);
 static struct cpumask scale_freq_counters_mask;
 static bool scale_freq_invariant;
 
@@ -66,16 +67,20 @@ void topology_set_scale_freq_source(struct scale_freq_data *data,
 	if (cpumask_empty(&scale_freq_counters_mask))
 		scale_freq_invariant = topology_scale_freq_invariant();
 
+	rcu_read_lock();
+
 	for_each_cpu(cpu, cpus) {
-		sfd = per_cpu(sft_data, cpu);
+		sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu));
 
 		/* Use ARCH provided counters whenever possible */
 		if (!sfd || sfd->source != SCALE_FREQ_SOURCE_ARCH) {
-			per_cpu(sft_data, cpu) = data;
+			rcu_assign_pointer(per_cpu(sft_data, cpu), data);
 			cpumask_set_cpu(cpu, &scale_freq_counters_mask);
 		}
 	}
 
+	rcu_read_unlock();
+
 	update_scale_freq_invariant(true);
 }
 EXPORT_SYMBOL_GPL(topology_set_scale_freq_source);
@@ -86,22 +91,32 @@ void topology_clear_scale_freq_source(enum scale_freq_source source,
 	struct scale_freq_data *sfd;
 	int cpu;
 
+	rcu_read_lock();
+
 	for_each_cpu(cpu, cpus) {
-		sfd = per_cpu(sft_data, cpu);
+		sfd = rcu_dereference(*per_cpu_ptr(&sft_data, cpu));
 
 		if (sfd && sfd->source == source) {
-			per_cpu(sft_data, cpu) = NULL;
+			rcu_assign_pointer(per_cpu(sft_data, cpu), NULL);
 			cpumask_clear_cpu(cpu, &scale_freq_counters_mask);
 		}
 	}
 
+	rcu_read_unlock();
+
+	/*
+	 * Make sure all references to previous sft_data are dropped to avoid
+	 * use-after-free races.
+	 */
+	synchronize_rcu();
+
 	update_scale_freq_invariant(false);
 }
 EXPORT_SYMBOL_GPL(topology_clear_scale_freq_source);
 
 void topology_scale_freq_tick(void)
 {
-	struct scale_freq_data *sfd = *this_cpu_ptr(&sft_data);
+	struct scale_freq_data *sfd = rcu_dereference_sched(*this_cpu_ptr(&sft_data));
 
 	if (sfd)
 		sfd->set_freq_scale();
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index ab0b740cc0f1..a934c679e6ce 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -2018,8 +2018,8 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
 
 	mutex_lock(&gpd_list_lock);
 	list_add(&genpd->gpd_list_node, &gpd_list);
-	genpd_debug_add(genpd);
 	mutex_unlock(&gpd_list_lock);
+	genpd_debug_add(genpd);
 
 	return 0;
 }
@@ -2206,12 +2206,19 @@ static int genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
 
 static bool genpd_present(const struct generic_pm_domain *genpd)
 {
+	bool ret = false;
 	const struct generic_pm_domain *gpd;
 
-	list_for_each_entry(gpd, &gpd_list, gpd_list_node)
-		if (gpd == genpd)
-			return true;
-	return false;
+	mutex_lock(&gpd_list_lock);
+	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
+		if (gpd == genpd) {
+			ret = true;
+			break;
+		}
+	}
+	mutex_unlock(&gpd_list_lock);
+
+	return ret;
 }
 
 /**
@@ -2222,15 +2229,13 @@ static bool genpd_present(const struct generic_pm_domain *genpd)
 int of_genpd_add_provider_simple(struct device_node *np,
 				 struct generic_pm_domain *genpd)
 {
-	int ret = -EINVAL;
+	int ret;
 
 	if (!np || !genpd)
 		return -EINVAL;
 
-	mutex_lock(&gpd_list_lock);
-
 	if (!genpd_present(genpd))
-		goto unlock;
+		return -EINVAL;
 
 	genpd->dev.of_node = np;
 
@@ -2241,7 +2246,7 @@ int of_genpd_add_provider_simple(struct device_node *np,
 			if (ret != -EPROBE_DEFER)
 				dev_err(&genpd->dev, "Failed to add OPP table: %d\n",
 					ret);
-			goto unlock;
+			return ret;
 		}
 
 		/*
@@ -2259,16 +2264,13 @@ int of_genpd_add_provider_simple(struct device_node *np,
 			dev_pm_opp_of_remove_table(&genpd->dev);
 		}
 
-		goto unlock;
+		return ret;
 	}
 
 	genpd->provider = &np->fwnode;
 	genpd->has_provider = true;
 
-unlock:
-	mutex_unlock(&gpd_list_lock);
-
-	return ret;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
 
@@ -2287,8 +2289,6 @@ int of_genpd_add_provider_onecell(struct device_node *np,
 	if (!np || !data)
 		return -EINVAL;
 
-	mutex_lock(&gpd_list_lock);
-
 	if (!data->xlate)
 		data->xlate = genpd_xlate_onecell;
 
@@ -2328,8 +2328,6 @@ int of_genpd_add_provider_onecell(struct device_node *np,
 	if (ret < 0)
 		goto error;
 
-	mutex_unlock(&gpd_list_lock);
-
 	return 0;
 
 error:
@@ -2348,8 +2346,6 @@ error:
 		}
 	}
 
-	mutex_unlock(&gpd_list_lock);
-
 	return ret;
 }
 EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index f893c3c5af07..d568772152c2 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -220,16 +220,13 @@ static void initcall_debug_report(struct device *dev, ktime_t calltime,
 				  void *cb, int error)
 {
 	ktime_t rettime;
-	s64 nsecs;
 
 	if (!pm_print_times_enabled)
 		return;
 
 	rettime = ktime_get();
-	nsecs = (s64) ktime_to_ns(ktime_sub(rettime, calltime));
-
 	dev_info(dev, "%pS returned %d after %Ld usecs\n", cb, error,
-		 (unsigned long long)nsecs >> 10);
+		 (unsigned long long)ktime_us_delta(rettime, calltime));
 }
 
 /**