24 files changed, 104 insertions, 73 deletions

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 6f2bfcf7645c..3c3f8037ebed 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -314,7 +314,6 @@ config ACPI_HOTPLUG_CPU
 	bool
 	depends on ACPI_PROCESSOR && HOTPLUG_CPU
 	select ACPI_CONTAINER
-	default y
 
 config ACPI_PROCESSOR_AGGREGATOR
 	tristate "Processor Aggregator"
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 0f5218e361df..4fe2ef54088c 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -184,24 +184,6 @@ static void __init acpi_pcc_cpufreq_init(void) {}
 
 /* Initialization */
 #ifdef CONFIG_ACPI_HOTPLUG_CPU
-int __weak acpi_map_cpu(acpi_handle handle,
-		phys_cpuid_t physid, u32 acpi_id, int *pcpu)
-{
-	return -ENODEV;
-}
-
-int __weak acpi_unmap_cpu(int cpu)
-{
-	return -ENODEV;
-}
-
-int __weak arch_register_cpu(int cpu)
-{
-	return -ENODEV;
-}
-
-void __weak arch_unregister_cpu(int cpu) {}
-
 static int acpi_processor_hotadd_init(struct acpi_processor *pr)
 {
 	unsigned long long sta;
diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 07d76fb740b6..a6ead5204046 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -881,6 +881,7 @@ static struct fwnode_handle *acpi_parse_string_ref(const struct fwnode_handle *f
  * @index: Index of the reference to return
  * @num_args: Maximum number of arguments after each reference
  * @args: Location to store the returned reference with optional arguments
+ *	  (may be NULL)
  *
  * Find property with @name, verifify that it is a package containing at least
  * one object reference and if so, store the ACPI device object pointer to the
@@ -938,6 +939,9 @@ int __acpi_node_get_property_reference(const struct fwnode_handle *fwnode,
 		if (!device)
 			return -EINVAL;
 
+		if (!args)
+			return 0;
+
 		args->fwnode = acpi_fwnode_handle(device);
 		args->nargs = 0;
 
diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
index 5aaa0865625d..018ac202de34 100644
--- a/drivers/base/arch_topology.c
+++ b/drivers/base/arch_topology.c
@@ -219,20 +219,34 @@ static DECLARE_WORK(update_topology_flags_work, update_topology_flags_workfn);
 
 static DEVICE_ATTR_RO(cpu_capacity);
 
-static int register_cpu_capacity_sysctl(void)
+static int cpu_capacity_sysctl_add(unsigned int cpu)
 {
-	int i;
-	struct device *cpu;
+	struct device *cpu_dev = get_cpu_device(cpu);
 
-	for_each_possible_cpu(i) {
-		cpu = get_cpu_device(i);
-		if (!cpu) {
-			pr_err("%s: too early to get CPU%d device!\n",
-			       __func__, i);
-			continue;
-		}
-		device_create_file(cpu, &dev_attr_cpu_capacity);
-	}
+	if (!cpu_dev)
+		return -ENOENT;
+
+	device_create_file(cpu_dev, &dev_attr_cpu_capacity);
+
+	return 0;
+}
+
+static int cpu_capacity_sysctl_remove(unsigned int cpu)
+{
+	struct device *cpu_dev = get_cpu_device(cpu);
+
+	if (!cpu_dev)
+		return -ENOENT;
+
+	device_remove_file(cpu_dev, &dev_attr_cpu_capacity);
+
+	return 0;
+}
+
+static int register_cpu_capacity_sysctl(void)
+{
+	cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "topology/cpu-capacity",
+			  cpu_capacity_sysctl_add, cpu_capacity_sysctl_remove);
 
 	return 0;
 }
diff --git a/drivers/base/auxiliary.c b/drivers/base/auxiliary.c
index 4d4c2c8d26c4..d3a2c40c2f12 100644
--- a/drivers/base/auxiliary.c
+++ b/drivers/base/auxiliary.c
@@ -244,7 +244,7 @@ static void auxiliary_bus_shutdown(struct device *dev)
 		auxdrv->shutdown(auxdev);
 }
 
-static struct bus_type auxiliary_bus_type = {
+static const struct bus_type auxiliary_bus_type = {
 	.name = "auxiliary",
 	.probe = auxiliary_bus_probe,
 	.remove = auxiliary_bus_remove,
diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 84a21084d67d..daee55c9b2d9 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -1030,7 +1030,7 @@ static void device_insertion_sort_klist(struct device *a, struct list_head *list
 	list_move_tail(&a->p->knode_bus.n_node, list);
 }
 
-void bus_sort_breadthfirst(struct bus_type *bus,
+void bus_sort_breadthfirst(const struct bus_type *bus,
 			   int (*compare)(const struct device *a,
 					  const struct device *b))
 {
@@ -1194,7 +1194,7 @@ static void system_root_device_release(struct device *dev)
 	kfree(dev);
 }
 
-static int subsys_register(struct bus_type *subsys,
+static int subsys_register(const struct bus_type *subsys,
 			   const struct attribute_group **groups,
 			   struct kobject *parent_of_root)
 {
@@ -1264,7 +1264,7 @@ err_sp:
  * directory itself and not some create fake root-device placed in
  * /sys/devices/system/<name>.
  */
-int subsys_system_register(struct bus_type *subsys,
+int subsys_system_register(const struct bus_type *subsys,
 			   const struct attribute_group **groups)
 {
 	return subsys_register(subsys, groups, &system_kset->kobj);
@@ -1282,7 +1282,7 @@ EXPORT_SYMBOL_GPL(subsys_system_register);
  * There's no restriction on device naming.  This is for kernel software
  * constructs which need sysfs interface.
  */
-int subsys_virtual_register(struct bus_type *subsys,
+int subsys_virtual_register(const struct bus_type *subsys,
 			    const struct attribute_group **groups)
 {
 	struct kobject *virtual_dir;
diff --git a/drivers/base/class.c b/drivers/base/class.c
index 7e78aee0fd6c..7b38fdf8e1d7 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -213,6 +213,7 @@ int class_register(const struct class *cls)
 	return 0;
 
 err_out:
+	lockdep_unregister_key(key);
 	kfree(cp);
 	return error;
 }
diff --git a/drivers/base/container.c b/drivers/base/container.c
index 1ba42d2d3532..f40588ebc3f5 100644
--- a/drivers/base/container.c
+++ b/drivers/base/container.c
@@ -24,7 +24,7 @@ static int container_offline(struct device *dev)
 	return cdev->offline ? cdev->offline(cdev) : 0;
 }
 
-struct bus_type container_subsys = {
+const struct bus_type container_subsys = {
 	.name = CONTAINER_BUS_NAME,
 	.dev_name = CONTAINER_BUS_NAME,
 	.online = trivial_online,
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 67ba592afc77..14d46af40f9a 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -298,7 +298,7 @@ static inline bool device_link_flag_is_sync_state_only(u32 flags)
  * Check if @target depends on @dev or any device dependent on it (its child or
  * its consumer etc).  Return 1 if that is the case or 0 otherwise.
  */
-int device_is_dependent(struct device *dev, void *target)
+static int device_is_dependent(struct device *dev, void *target)
 {
 	struct device_link *link;
 	int ret;
@@ -1641,7 +1641,7 @@ static void device_links_purge(struct device *dev)
 #define FW_DEVLINK_FLAGS_RPM		(FW_DEVLINK_FLAGS_ON | \
 					 DL_FLAG_PM_RUNTIME)
 
-static u32 fw_devlink_flags = FW_DEVLINK_FLAGS_ON;
+static u32 fw_devlink_flags = FW_DEVLINK_FLAGS_RPM;
 static int __init fw_devlink_setup(char *arg)
 {
 	if (!arg)
@@ -4944,13 +4944,14 @@ define_dev_printk_level(_dev_info, KERN_INFO);
  *
  * 	return dev_err_probe(dev, err, ...);
  *
- * Note that it is deemed acceptable to use this function for error
- * prints during probe even if the @err is known to never be -EPROBE_DEFER.
+ * Using this helper in your probe function is totally fine even if @err is
+ * known to never be -EPROBE_DEFER.
  * The benefit compared to a normal dev_err() is the standardized format
- * of the error code and the fact that the error code is returned.
+ * of the error code, it being emitted symbolically (i.e. you get "EAGAIN"
+ * instead of "-35") and the fact that the error code is returned which allows
+ * more compact error paths.
  *
  * Returns @err.
- *
  */
 int dev_err_probe(const struct device *dev, int err, const char *fmt, ...)
 {
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 548491de818e..47de0f140ba6 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -525,19 +525,42 @@ bool cpu_is_hotpluggable(unsigned int cpu)
 EXPORT_SYMBOL_GPL(cpu_is_hotpluggable);
 
 #ifdef CONFIG_GENERIC_CPU_DEVICES
-static DEFINE_PER_CPU(struct cpu, cpu_devices);
-#endif
+DEFINE_PER_CPU(struct cpu, cpu_devices);
+
+bool __weak arch_cpu_is_hotpluggable(int cpu)
+{
+	return false;
+}
+
+int __weak arch_register_cpu(int cpu)
+{
+	struct cpu *c = &per_cpu(cpu_devices, cpu);
+
+	c->hotpluggable = arch_cpu_is_hotpluggable(cpu);
+
+	return register_cpu(c, cpu);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+void __weak arch_unregister_cpu(int num)
+{
+	unregister_cpu(&per_cpu(cpu_devices, num));
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+#endif /* CONFIG_GENERIC_CPU_DEVICES */
 
 static void __init cpu_dev_register_generic(void)
 {
-#ifdef CONFIG_GENERIC_CPU_DEVICES
-	int i;
+	int i, ret;
 
-	for_each_possible_cpu(i) {
-		if (register_cpu(&per_cpu(cpu_devices, i), i))
-			panic("Failed to register CPU device");
+	if (!IS_ENABLED(CONFIG_GENERIC_CPU_DEVICES))
+		return;
+
+	for_each_present_cpu(i) {
+		ret = arch_register_cpu(i);
+		if (ret)
+			pr_warn("register_cpu %d failed (%d)\n", i, ret);
 	}
-#endif
 }
 
 #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 0c3725c3eefa..85152537dbf1 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -313,7 +313,7 @@ static void deferred_probe_timeout_work_func(struct work_struct *work)
 
 	mutex_lock(&deferred_probe_mutex);
 	list_for_each_entry(p, &deferred_probe_pending_list, deferred_probe)
-		dev_info(p->device, "deferred probe pending\n");
+		dev_info(p->device, "deferred probe pending: %s", p->deferred_probe_reason ?: "(reason unknown)\n");
 	mutex_unlock(&deferred_probe_mutex);
 
 	fw_devlink_probing_done();
diff --git a/drivers/base/init.c b/drivers/base/init.c
index 397eb9880cec..c4954835128c 100644
--- a/drivers/base/init.c
+++ b/drivers/base/init.c
@@ -35,8 +35,8 @@ void __init driver_init(void)
 	of_core_init();
 	platform_bus_init();
 	auxiliary_bus_init();
-	cpu_dev_init();
 	memory_dev_init();
 	node_dev_init();
+	cpu_dev_init();
 	container_dev_init();
 }
diff --git a/drivers/base/isa.c b/drivers/base/isa.c
index 675ad3139224..e23d0b49a793 100644
--- a/drivers/base/isa.c
+++ b/drivers/base/isa.c
@@ -82,7 +82,7 @@ static int isa_bus_resume(struct device *dev)
 	return 0;
 }
 
-static struct bus_type isa_bus_type = {
+static const struct bus_type isa_bus_type = {
 	.name		= "isa",
 	.match		= isa_bus_match,
 	.probe		= isa_bus_probe,
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 8a13babd826c..14f964a7719b 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -68,7 +68,7 @@ static inline unsigned long phys_to_block_id(unsigned long phys)
 static int memory_subsys_online(struct device *dev);
 static int memory_subsys_offline(struct device *dev);
 
-static struct bus_type memory_subsys = {
+static const struct bus_type memory_subsys = {
 	.name = MEMORY_CLASS_NAME,
 	.dev_name = MEMORY_CLASS_NAME,
 	.online = memory_subsys_online,
diff --git a/drivers/base/node.c b/drivers/base/node.c
index 493d533f8375..433897eecbdc 100644
--- a/drivers/base/node.c
+++ b/drivers/base/node.c
@@ -21,7 +21,7 @@
 #include <linux/swap.h>
 #include <linux/slab.h>
 
-static struct bus_type node_subsys = {
+static const struct bus_type node_subsys = {
 	.name = "node",
 	.dev_name = "node",
 };
@@ -868,11 +868,15 @@ int __register_one_node(int nid)
 {
 	int error;
 	int cpu;
+	struct node *node;
 
-	node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
-	if (!node_devices[nid])
+	node = kzalloc(sizeof(struct node), GFP_KERNEL);
+	if (!node)
 		return -ENOMEM;
 
+	INIT_LIST_HEAD(&node->access_list);
+	node_devices[nid] = node;
+
 	error = register_node(node_devices[nid], nid);
 
 	/* link cpu under this node */
@@ -881,7 +885,6 @@ int __register_one_node(int nid)
 			register_cpu_under_node(cpu, nid);
 	}
 
-	INIT_LIST_HEAD(&node_devices[nid]->access_list);
 	node_init_caches(nid);
 
 	return error;
diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c
index 4110c19c08dc..e18ba676cdf6 100644
--- a/drivers/base/power/clock_ops.c
+++ b/drivers/base/power/clock_ops.c
@@ -793,7 +793,7 @@ static int pm_clk_notify(struct notifier_block *nb,
  * the remaining members of @clknb should be populated prior to calling this
  * routine.
  */
-void pm_clk_add_notifier(struct bus_type *bus,
+void pm_clk_add_notifier(const struct bus_type *bus,
 				 struct pm_clk_notifier_block *clknb)
 {
 	if (!bus || !clknb)
diff --git a/drivers/base/property.c b/drivers/base/property.c
index 6e39db62446d..a1b01ab42052 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -543,6 +543,7 @@ EXPORT_SYMBOL_GPL(fwnode_property_match_property_string);
  * @nargs:	Number of arguments. Ignored if @nargs_prop is non-NULL.
  * @index:	Index of the reference, from zero onwards.
  * @args:	Result structure with reference and integer arguments.
+ *		May be NULL.
  *
  * Obtain a reference based on a named property in an fwnode, with
  * integer arguments.
diff --git a/drivers/base/soc.c b/drivers/base/soc.c
index 8dec5228fde3..282c38aece0d 100644
--- a/drivers/base/soc.c
+++ b/drivers/base/soc.c
@@ -28,7 +28,7 @@ struct soc_device {
 	int soc_dev_num;
 };
 
-static struct bus_type soc_bus_type = {
+static const struct bus_type soc_bus_type = {
 	.name  = "soc",
 };
 static bool soc_bus_registered;
@@ -106,7 +106,7 @@ static void soc_release(struct device *dev)
 {
 	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev);
 
-	ida_simple_remove(&soc_ida, soc_dev->soc_dev_num);
+	ida_free(&soc_ida, soc_dev->soc_dev_num);
 	kfree(soc_dev->dev.groups);
 	kfree(soc_dev);
 }
@@ -155,7 +155,7 @@ struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr
 	soc_attr_groups[1] = soc_dev_attr->custom_attr_group;
 
 	/* Fetch a unique (reclaimable) SOC ID. */
-	ret = ida_simple_get(&soc_ida, 0, 0, GFP_KERNEL);
+	ret = ida_alloc(&soc_ida, GFP_KERNEL);
 	if (ret < 0)
 		goto out3;
 	soc_dev->soc_dev_num = ret;
diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index 1886995a0b3a..36512fb75a20 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -541,6 +541,9 @@ software_node_get_reference_args(const struct fwnode_handle *fwnode,
 	if (nargs > NR_FWNODE_REFERENCE_ARGS)
 		return -EINVAL;
 
+	if (!args)
+		return 0;
+
 	args->fwnode = software_node_get(refnode);
 	args->nargs = nargs;
 
@@ -747,10 +750,10 @@ static void software_node_release(struct kobject *kobj)
 	struct swnode *swnode = kobj_to_swnode(kobj);
 
 	if (swnode->parent) {
-		ida_simple_remove(&swnode->parent->child_ids, swnode->id);
+		ida_free(&swnode->parent->child_ids, swnode->id);
 		list_del(&swnode->entry);
 	} else {
-		ida_simple_remove(&swnode_root_ids, swnode->id);
+		ida_free(&swnode_root_ids, swnode->id);
 	}
 
 	if (swnode->allocated)
@@ -776,8 +779,8 @@ swnode_register(const struct software_node *node, struct swnode *parent,
 	if (!swnode)
 		return ERR_PTR(-ENOMEM);
 
-	ret = ida_simple_get(parent ? &parent->child_ids : &swnode_root_ids,
-			     0, 0, GFP_KERNEL);
+	ret = ida_alloc(parent ? &parent->child_ids : &swnode_root_ids,
+			GFP_KERNEL);
 	if (ret < 0) {
 		kfree(swnode);
 		return ERR_PTR(ret);
diff --git a/drivers/edac/edac_device.h b/drivers/edac/edac_device.h
index 3f44e6b9d387..7db22a4c83ef 100644
--- a/drivers/edac/edac_device.h
+++ b/drivers/edac/edac_device.h
@@ -176,7 +176,7 @@ struct edac_device_ctl_info {
 	struct edac_dev_sysfs_attribute *sysfs_attributes;
 
 	/* pointer to main 'edac' subsys in sysfs */
-	struct bus_type *edac_subsys;
+	const struct bus_type *edac_subsys;
 
 	/* the internal state of this controller instance */
 	int op_state;
diff --git a/drivers/edac/edac_device_sysfs.c b/drivers/edac/edac_device_sysfs.c
index 010c26be5846..237a542e045a 100644
--- a/drivers/edac/edac_device_sysfs.c
+++ b/drivers/edac/edac_device_sysfs.c
@@ -229,7 +229,7 @@ static struct kobj_type ktype_device_ctrl = {
 int edac_device_register_sysfs_main_kobj(struct edac_device_ctl_info *edac_dev)
 {
 	struct device *dev_root;
-	struct bus_type *edac_subsys;
+	const struct bus_type *edac_subsys;
 	int err = -ENODEV;
 
 	edac_dbg(1, "\n");
diff --git a/drivers/edac/edac_module.c b/drivers/edac/edac_module.c
index 32a931d0cb71..1c9f62382666 100644
--- a/drivers/edac/edac_module.c
+++ b/drivers/edac/edac_module.c
@@ -67,7 +67,7 @@ char *edac_op_state_to_string(int opstate)
  * sysfs object: /sys/devices/system/edac
  *	need to export to other files
  */
-static struct bus_type edac_subsys = {
+static const struct bus_type edac_subsys = {
 	.name = "edac",
 	.dev_name = "edac",
 };
@@ -90,7 +90,7 @@ static void edac_subsys_exit(void)
 }
 
 /* return pointer to the 'edac' node in sysfs */
-struct bus_type *edac_get_sysfs_subsys(void)
+const struct bus_type *edac_get_sysfs_subsys(void)
 {
 	return &edac_subsys;
 }
diff --git a/drivers/edac/edac_pci_sysfs.c b/drivers/edac/edac_pci_sysfs.c
index 901d4cd3ca38..7b44afcf48db 100644
--- a/drivers/edac/edac_pci_sysfs.c
+++ b/drivers/edac/edac_pci_sysfs.c
@@ -338,7 +338,7 @@ static struct kobj_type ktype_edac_pci_main_kobj = {
 static int edac_pci_main_kobj_setup(void)
 {
 	int err = -ENODEV;
-	struct bus_type *edac_subsys;
+	const struct bus_type *edac_subsys;
 	struct device *dev_root;
 
 	edac_dbg(0, "\n");
diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c
index 9ee1bf2ece10..a1f6cba3ae6c 100644
--- a/drivers/pmdomain/core.c
+++ b/drivers/pmdomain/core.c
@@ -2668,7 +2668,7 @@ static void genpd_release_dev(struct device *dev)
 	kfree(dev);
 }
 
-static struct bus_type genpd_bus_type = {
+static const struct bus_type genpd_bus_type = {
 	.name		= "genpd",
 };