3 files changed, 48 insertions, 17 deletions

diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
index 61a33f4ba608..df04227d00cf 100644
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -171,20 +171,23 @@ config WANT_DEV_COREDUMP
           Drivers should "select" this option if they desire to use the
           device coredump mechanism.
 
-config DISABLE_DEV_COREDUMP
-        bool "Disable device coredump" if EXPERT
+config ALLOW_DEV_COREDUMP
+        bool "Allow device coredump" if EXPERT
+        default y
         help
-          Disable the device coredump mechanism despite drivers wanting to
-          use it; this allows for more sensitive systems or systems that
-          don't want to ever access the information to not have the code,
-          nor keep any data.
+          This option controls if the device coredump mechanism is available or
+          not; if disabled, the mechanism will be omitted even if drivers that
+          can use it are enabled.
+          Say 'N' for more sensitive systems or systems that don't want
+          to ever access the information to not have the code, nor keep any
+          data.
 
-          If unsure, say N.
+          If unsure, say Y.
 
 config DEV_COREDUMP
         bool
         default y if WANT_DEV_COREDUMP
-        depends on !DISABLE_DEV_COREDUMP
+        depends on ALLOW_DEV_COREDUMP
 
 config DEBUG_DRIVER
         bool "Driver Core verbose debug messages"
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 14d162952c3b..842d04707de6 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -724,12 +724,12 @@ class_dir_create_and_add(struct class *class, struct kobject *parent_kobj)
         return &dir->kobj;
 }
 
+static DEFINE_MUTEX(gdp_mutex);
 
 static struct kobject *get_device_parent(struct device *dev,
                                          struct device *parent)
 {
         if (dev->class) {
-                static DEFINE_MUTEX(gdp_mutex);
                 struct kobject *kobj = NULL;
                 struct kobject *parent_kobj;
                 struct kobject *k;
@@ -793,7 +793,9 @@ static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir)
             glue_dir->kset != &dev->class->p->glue_dirs)
                 return;
 
+        mutex_lock(&gdp_mutex);
         kobject_put(glue_dir);
+        mutex_unlock(&gdp_mutex);
 }
 
 static void cleanup_device_parent(struct device *dev)
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 40bc2f4072cc..fb83d4acd400 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -361,9 +361,19 @@ static int __pm_genpd_save_device(struct pm_domain_data *pdd,
         struct device *dev = pdd->dev;
         int ret = 0;
 
-        if (gpd_data->need_restore)
+        if (gpd_data->need_restore > 0)
                 return 0;
 
+        /*
+         * If the value of the need_restore flag is still unknown at this point,
+         * we trust that pm_genpd_poweroff() has verified that the device is
+         * already runtime PM suspended.
+         */
+        if (gpd_data->need_restore < 0) {
+                gpd_data->need_restore = 1;
+                return 0;
+        }
+
         mutex_unlock(&genpd->lock);
 
         genpd_start_dev(genpd, dev);
@@ -373,7 +383,7 @@ static int __pm_genpd_save_device(struct pm_domain_data *pdd,
         mutex_lock(&genpd->lock);
 
         if (!ret)
-                gpd_data->need_restore = true;
+                gpd_data->need_restore = 1;
 
         return ret;
 }
@@ -389,12 +399,17 @@ static void __pm_genpd_restore_device(struct pm_domain_data *pdd,
 {
         struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
         struct device *dev = pdd->dev;
-        bool need_restore = gpd_data->need_restore;
+        int need_restore = gpd_data->need_restore;
 
-        gpd_data->need_restore = false;
+        gpd_data->need_restore = 0;
         mutex_unlock(&genpd->lock);
 
         genpd_start_dev(genpd, dev);
+
+        /*
+         * Call genpd_restore_dev() for recently added devices too (need_restore
+         * is negative then).
+         */
         if (need_restore)
                 genpd_restore_dev(genpd, dev);
 
@@ -603,6 +618,7 @@ static void genpd_power_off_work_fn(struct work_struct *work)
 static int pm_genpd_runtime_suspend(struct device *dev)
 {
         struct generic_pm_domain *genpd;
+        struct generic_pm_domain_data *gpd_data;
         bool (*stop_ok)(struct device *__dev);
         int ret;
 
@@ -628,6 +644,16 @@ static int pm_genpd_runtime_suspend(struct device *dev)
                 return 0;
 
         mutex_lock(&genpd->lock);
+
+        /*
+         * If we have an unknown state of the need_restore flag, it means none
+         * of the runtime PM callbacks has been invoked yet. Let's update the
+         * flag to reflect that the current state is active.
+         */
+        gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
+        if (gpd_data->need_restore < 0)
+                gpd_data->need_restore = 0;
+
         genpd->in_progress++;
         pm_genpd_poweroff(genpd);
         genpd->in_progress--;
@@ -1437,12 +1463,12 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
         spin_unlock_irq(&dev->power.lock);
 
         if (genpd->attach_dev)
-                genpd->attach_dev(dev);
+                genpd->attach_dev(genpd, dev);
 
         mutex_lock(&gpd_data->lock);
         gpd_data->base.dev = dev;
         list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
-        gpd_data->need_restore = genpd->status == GPD_STATE_POWER_OFF;
+        gpd_data->need_restore = -1;
         gpd_data->td.constraint_changed = true;
         gpd_data->td.effective_constraint_ns = -1;
         mutex_unlock(&gpd_data->lock);
@@ -1499,7 +1525,7 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
         genpd->max_off_time_changed = true;
 
         if (genpd->detach_dev)
-                genpd->detach_dev(dev);
+                genpd->detach_dev(genpd, dev);
 
         spin_lock_irq(&dev->power.lock);
 
@@ -1546,7 +1572,7 @@ void pm_genpd_dev_need_restore(struct device *dev, bool val)
 
         psd = dev_to_psd(dev);
         if (psd && psd->domain_data)
-                to_gpd_data(psd->domain_data)->need_restore = val;
+                to_gpd_data(psd->domain_data)->need_restore = val ? 1 : 0;
 
         spin_unlock_irqrestore(&dev->power.lock, flags);
 }