Merge tag 'driver-core-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the "big" set of changes to the driver core, and some drivers
  using the changes, for 5.9-rc1.

  "Biggest" thing in here is the device link exposure in sysfs, to help
  to tame the madness that is SoC device tree representations and driver
  interactions with it.

  Other stuff in here that is interesting is:

   - device probe log helper so that drivers can report problems in a
     unified way easier.

   - devres functions added

   - DEVICE_ATTR_ADMIN_* macro added to make it harder to write
     incorrect sysfs file permissions

   - documentation cleanups

   - ability for debugfs to be present in the kernel, yet not exposed to
     userspace. Needed for systems that want it enabled, but do not
     trust users, so they can still use some kernel functions that were
     otherwise disabled.

   - other minor fixes and cleanups

  The patches outside of drivers/base/ all have acks from the respective
  subsystem maintainers to go through this tree instead of theirs.

  All of these have been in linux-next with no reported issues"

* tag 'driver-core-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (39 commits)
  drm/bridge: lvds-codec: simplify error handling
  drm/bridge/sii8620: fix resource acquisition error handling
  driver core: add deferring probe reason to devices_deferred property
  driver core: add device probe log helper
  driver core: Avoid binding drivers to dead devices
  Revert "test_firmware: Test platform fw loading on non-EFI systems"
  firmware_loader: EFI firmware loader must handle pre-allocated buffer
  selftest/firmware: Add selftest timeout in settings
  test_firmware: Test platform fw loading on non-EFI systems
  driver core: Change delimiter in devlink device's name to "--"
  debugfs: Add access restriction option
  tracefs: Remove unnecessary debug_fs checks.
  driver core: Fix probe_count imbalance in really_probe()
  kobject: remove unused KOBJ_MAX action
  driver core: Fix sleeping in invalid context during device link deletion
  driver core: Add waiting_for_supplier sysfs file for devices
  driver core: Add state_synced sysfs file for devices that support it
  driver core: Expose device link details in sysfs
  driver core: Drop mention of obsolete bus rwsem from kernel-doc
  debugfs: file: Remove unnecessary cast in kfree()
  ...

13 files changed, 434 insertions, 86 deletions

diff --git a/drivers/base/base.h b/drivers/base/base.h
index 40fb069a8a7e..91cfb8405abd 100644
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -93,6 +93,7 @@ struct device_private {
 	struct klist_node knode_class;
 	struct list_head deferred_probe;
 	struct device_driver *async_driver;
+	char *deferred_probe_reason;
 	struct device *device;
 	u8 dead:1;
 };
@@ -134,6 +135,8 @@ extern void device_release_driver_internal(struct device *dev,
 extern void driver_detach(struct device_driver *drv);
 extern int driver_probe_device(struct device_driver *drv, struct device *dev);
 extern void driver_deferred_probe_del(struct device *dev);
+extern void device_set_deferred_probe_reason(const struct device *dev,
+					     struct va_format *vaf);
 static inline int driver_match_device(struct device_driver *drv,
 				      struct device *dev)
 {
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 05d414e9e8a4..778c7a435cbd 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -236,6 +236,210 @@ void device_pm_move_to_tail(struct device *dev)
 	device_links_read_unlock(idx);
 }
 
+#define to_devlink(dev)	container_of((dev), struct device_link, link_dev)
+
+static ssize_t status_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	char *status;
+
+	switch (to_devlink(dev)->status) {
+	case DL_STATE_NONE:
+		status = "not tracked"; break;
+	case DL_STATE_DORMANT:
+		status = "dormant"; break;
+	case DL_STATE_AVAILABLE:
+		status = "available"; break;
+	case DL_STATE_CONSUMER_PROBE:
+		status = "consumer probing"; break;
+	case DL_STATE_ACTIVE:
+		status = "active"; break;
+	case DL_STATE_SUPPLIER_UNBIND:
+		status = "supplier unbinding"; break;
+	default:
+		status = "unknown"; break;
+	}
+	return sprintf(buf, "%s\n", status);
+}
+static DEVICE_ATTR_RO(status);
+
+static ssize_t auto_remove_on_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct device_link *link = to_devlink(dev);
+	char *str;
+
+	if (link->flags & DL_FLAG_AUTOREMOVE_SUPPLIER)
+		str = "supplier unbind";
+	else if (link->flags & DL_FLAG_AUTOREMOVE_CONSUMER)
+		str = "consumer unbind";
+	else
+		str = "never";
+
+	return sprintf(buf, "%s\n", str);
+}
+static DEVICE_ATTR_RO(auto_remove_on);
+
+static ssize_t runtime_pm_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct device_link *link = to_devlink(dev);
+
+	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_PM_RUNTIME));
+}
+static DEVICE_ATTR_RO(runtime_pm);
+
+static ssize_t sync_state_only_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct device_link *link = to_devlink(dev);
+
+	return sprintf(buf, "%d\n", !!(link->flags & DL_FLAG_SYNC_STATE_ONLY));
+}
+static DEVICE_ATTR_RO(sync_state_only);
+
+static struct attribute *devlink_attrs[] = {
+	&dev_attr_status.attr,
+	&dev_attr_auto_remove_on.attr,
+	&dev_attr_runtime_pm.attr,
+	&dev_attr_sync_state_only.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(devlink);
+
+static void device_link_free(struct device_link *link)
+{
+	while (refcount_dec_not_one(&link->rpm_active))
+		pm_runtime_put(link->supplier);
+
+	put_device(link->consumer);
+	put_device(link->supplier);
+	kfree(link);
+}
+
+#ifdef CONFIG_SRCU
+static void __device_link_free_srcu(struct rcu_head *rhead)
+{
+	device_link_free(container_of(rhead, struct device_link, rcu_head));
+}
+
+static void devlink_dev_release(struct device *dev)
+{
+	struct device_link *link = to_devlink(dev);
+
+	call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu);
+}
+#else
+static void devlink_dev_release(struct device *dev)
+{
+	device_link_free(to_devlink(dev));
+}
+#endif
+
+static struct class devlink_class = {
+	.name = "devlink",
+	.owner = THIS_MODULE,
+	.dev_groups = devlink_groups,
+	.dev_release = devlink_dev_release,
+};
+
+static int devlink_add_symlinks(struct device *dev,
+				struct class_interface *class_intf)
+{
+	int ret;
+	size_t len;
+	struct device_link *link = to_devlink(dev);
+	struct device *sup = link->supplier;
+	struct device *con = link->consumer;
+	char *buf;
+
+	len = max(strlen(dev_name(sup)), strlen(dev_name(con)));
+	len += strlen("supplier:") + 1;
+	buf = kzalloc(len, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = sysfs_create_link(&link->link_dev.kobj, &sup->kobj, "supplier");
+	if (ret)
+		goto out;
+
+	ret = sysfs_create_link(&link->link_dev.kobj, &con->kobj, "consumer");
+	if (ret)
+		goto err_con;
+
+	snprintf(buf, len, "consumer:%s", dev_name(con));
+	ret = sysfs_create_link(&sup->kobj, &link->link_dev.kobj, buf);
+	if (ret)
+		goto err_con_dev;
+
+	snprintf(buf, len, "supplier:%s", dev_name(sup));
+	ret = sysfs_create_link(&con->kobj, &link->link_dev.kobj, buf);
+	if (ret)
+		goto err_sup_dev;
+
+	goto out;
+
+err_sup_dev:
+	snprintf(buf, len, "consumer:%s", dev_name(con));
+	sysfs_remove_link(&sup->kobj, buf);
+err_con_dev:
+	sysfs_remove_link(&link->link_dev.kobj, "consumer");
+err_con:
+	sysfs_remove_link(&link->link_dev.kobj, "supplier");
+out:
+	kfree(buf);
+	return ret;
+}
+
+static void devlink_remove_symlinks(struct device *dev,
+				   struct class_interface *class_intf)
+{
+	struct device_link *link = to_devlink(dev);
+	size_t len;
+	struct device *sup = link->supplier;
+	struct device *con = link->consumer;
+	char *buf;
+
+	sysfs_remove_link(&link->link_dev.kobj, "consumer");
+	sysfs_remove_link(&link->link_dev.kobj, "supplier");
+
+	len = max(strlen(dev_name(sup)), strlen(dev_name(con)));
+	len += strlen("supplier:") + 1;
+	buf = kzalloc(len, GFP_KERNEL);
+	if (!buf) {
+		WARN(1, "Unable to properly free device link symlinks!\n");
+		return;
+	}
+
+	snprintf(buf, len, "supplier:%s", dev_name(sup));
+	sysfs_remove_link(&con->kobj, buf);
+	snprintf(buf, len, "consumer:%s", dev_name(con));
+	sysfs_remove_link(&sup->kobj, buf);
+	kfree(buf);
+}
+
+static struct class_interface devlink_class_intf = {
+	.class = &devlink_class,
+	.add_dev = devlink_add_symlinks,
+	.remove_dev = devlink_remove_symlinks,
+};
+
+static int __init devlink_class_init(void)
+{
+	int ret;
+
+	ret = class_register(&devlink_class);
+	if (ret)
+		return ret;
+
+	ret = class_interface_register(&devlink_class_intf);
+	if (ret)
+		class_unregister(&devlink_class);
+
+	return ret;
+}
+postcore_initcall(devlink_class_init);
+
 #define DL_MANAGED_LINK_FLAGS (DL_FLAG_AUTOREMOVE_CONSUMER | \
 			       DL_FLAG_AUTOREMOVE_SUPPLIER | \
 			       DL_FLAG_AUTOPROBE_CONSUMER  | \
@@ -408,13 +612,6 @@ struct device_link *device_link_add(struct device *consumer,
 
 	refcount_set(&link->rpm_active, 1);
 
-	if (flags & DL_FLAG_PM_RUNTIME) {
-		if (flags & DL_FLAG_RPM_ACTIVE)
-			refcount_inc(&link->rpm_active);
-
-		pm_runtime_new_link(consumer);
-	}
-
 	get_device(supplier);
 	link->supplier = supplier;
 	INIT_LIST_HEAD(&link->s_node);
@@ -424,6 +621,25 @@ struct device_link *device_link_add(struct device *consumer,
 	link->flags = flags;
 	kref_init(&link->kref);
 
+	link->link_dev.class = &devlink_class;
+	device_set_pm_not_required(&link->link_dev);
+	dev_set_name(&link->link_dev, "%s--%s",
+		     dev_name(supplier), dev_name(consumer));
+	if (device_register(&link->link_dev)) {
+		put_device(consumer);
+		put_device(supplier);
+		kfree(link);
+		link = NULL;
+		goto out;
+	}
+
+	if (flags & DL_FLAG_PM_RUNTIME) {
+		if (flags & DL_FLAG_RPM_ACTIVE)
+			refcount_inc(&link->rpm_active);
+
+		pm_runtime_new_link(consumer);
+	}
+
 	/* Determine the initial link state. */
 	if (flags & DL_FLAG_STATELESS)
 		link->status = DL_STATE_NONE;
@@ -539,22 +755,7 @@ static void device_link_add_missing_supplier_links(void)
 	mutex_unlock(&wfs_lock);
 }
 
-static void device_link_free(struct device_link *link)
-{
-	while (refcount_dec_not_one(&link->rpm_active))
-		pm_runtime_put(link->supplier);
-
-	put_device(link->consumer);
-	put_device(link->supplier);
-	kfree(link);
-}
-
 #ifdef CONFIG_SRCU
-static void __device_link_free_srcu(struct rcu_head *rhead)
-{
-	device_link_free(container_of(rhead, struct device_link, rcu_head));
-}
-
 static void __device_link_del(struct kref *kref)
 {
 	struct device_link *link = container_of(kref, struct device_link, kref);
@@ -567,7 +768,7 @@ static void __device_link_del(struct kref *kref)
 
 	list_del_rcu(&link->s_node);
 	list_del_rcu(&link->c_node);
-	call_srcu(&device_links_srcu, &link->rcu_head, __device_link_free_srcu);
+	device_unregister(&link->link_dev);
 }
 #else /* !CONFIG_SRCU */
 static void __device_link_del(struct kref *kref)
@@ -582,7 +783,7 @@ static void __device_link_del(struct kref *kref)
 
 	list_del(&link->s_node);
 	list_del(&link->c_node);
-	device_link_free(link);
+	device_unregister(&link->link_dev);
 }
 #endif /* !CONFIG_SRCU */
 
@@ -850,6 +1051,22 @@ static void device_link_drop_managed(struct device_link *link)
 	kref_put(&link->kref, __device_link_del);
 }
 
+static ssize_t waiting_for_supplier_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	bool val;
+
+	device_lock(dev);
+	mutex_lock(&wfs_lock);
+	val = !list_empty(&dev->links.needs_suppliers)
+	      && dev->links.need_for_probe;
+	mutex_unlock(&wfs_lock);
+	device_unlock(dev);
+	return sprintf(buf, "%u\n", val);
+}
+static DEVICE_ATTR_RO(waiting_for_supplier);
+
 /**
  * device_links_driver_bound - Update device links after probing its driver.
  * @dev: Device to update the links for.
@@ -874,6 +1091,7 @@ void device_links_driver_bound(struct device *dev)
 	mutex_lock(&wfs_lock);
 	list_del_init(&dev->links.needs_suppliers);
 	mutex_unlock(&wfs_lock);
+	device_remove_file(dev, &dev_attr_waiting_for_supplier);
 
 	device_links_write_lock();
 
@@ -1160,6 +1378,9 @@ static void device_links_purge(struct device *dev)
 {
 	struct device_link *link, *ln;
 
+	if (dev->class == &devlink_class)
+		return;
+
 	mutex_lock(&wfs_lock);
 	list_del(&dev->links.needs_suppliers);
 	mutex_unlock(&wfs_lock);
@@ -1969,8 +2190,16 @@ static int device_add_attrs(struct device *dev)
 			goto err_remove_dev_groups;
 	}
 
+	if (fw_devlink_flags && !fw_devlink_is_permissive()) {
+		error = device_create_file(dev, &dev_attr_waiting_for_supplier);
+		if (error)
+			goto err_remove_dev_online;
+	}
+
 	return 0;
 
+ err_remove_dev_online:
+	device_remove_file(dev, &dev_attr_online);
  err_remove_dev_groups:
 	device_remove_groups(dev, dev->groups);
  err_remove_type_groups:
@@ -1988,6 +2217,7 @@ static void device_remove_attrs(struct device *dev)
 	struct class *class = dev->class;
 	const struct device_type *type = dev->type;
 
+	device_remove_file(dev, &dev_attr_waiting_for_supplier);
 	device_remove_file(dev, &dev_attr_online);
 	device_remove_groups(dev, dev->groups);
 
@@ -3973,6 +4203,52 @@ define_dev_printk_level(_dev_info, KERN_INFO);
 
 #endif
 
+/**
+ * dev_err_probe - probe error check and log helper
+ * @dev: the pointer to the struct device
+ * @err: error value to test
+ * @fmt: printf-style format string
+ * @...: arguments as specified in the format string
+ *
+ * This helper implements common pattern present in probe functions for error
+ * checking: print debug or error message depending if the error value is
+ * -EPROBE_DEFER and propagate error upwards.
+ * In case of -EPROBE_DEFER it sets also defer probe reason, which can be
+ * checked later by reading devices_deferred debugfs attribute.
+ * It replaces code sequence:
+ * 	if (err != -EPROBE_DEFER)
+ * 		dev_err(dev, ...);
+ * 	else
+ * 		dev_dbg(dev, ...);
+ * 	return err;
+ * with
+ * 	return dev_err_probe(dev, err, ...);
+ *
+ * Returns @err.
+ *
+ */
+int dev_err_probe(const struct device *dev, int err, const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start(args, fmt);
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	if (err != -EPROBE_DEFER) {
+		dev_err(dev, "error %d: %pV", err, &vaf);
+	} else {
+		device_set_deferred_probe_reason(dev, &vaf);
+		dev_dbg(dev, "error %d: %pV", err, &vaf);
+	}
+
+	va_end(args);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(dev_err_probe);
+
 static inline bool fwnode_is_primary(struct fwnode_handle *fwnode)
 {
 	return fwnode && !IS_ERR(fwnode->secondary);
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 48ca81cb8ebc..857b0a928e8d 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -27,6 +27,7 @@
 #include <linux/async.h>
 #include <linux/pm_runtime.h>
 #include <linux/pinctrl/devinfo.h>
+#include <linux/slab.h>
 
 #include "base.h"
 #include "power/power.h"
@@ -136,6 +137,8 @@ void driver_deferred_probe_del(struct device *dev)
 	if (!list_empty(&dev->p->deferred_probe)) {
 		dev_dbg(dev, "Removed from deferred list\n");
 		list_del_init(&dev->p->deferred_probe);
+		kfree(dev->p->deferred_probe_reason);
+		dev->p->deferred_probe_reason = NULL;
 	}
 	mutex_unlock(&deferred_probe_mutex);
 }
@@ -206,6 +209,23 @@ void device_unblock_probing(void)
 	driver_deferred_probe_trigger();
 }
 
+/**
+ * device_set_deferred_probe_reason() - Set defer probe reason message for device
+ * @dev: the pointer to the struct device
+ * @vaf: the pointer to va_format structure with message
+ */
+void device_set_deferred_probe_reason(const struct device *dev, struct va_format *vaf)
+{
+	const char *drv = dev_driver_string(dev);
+
+	mutex_lock(&deferred_probe_mutex);
+
+	kfree(dev->p->deferred_probe_reason);
+	dev->p->deferred_probe_reason = kasprintf(GFP_KERNEL, "%s: %pV", drv, vaf);
+
+	mutex_unlock(&deferred_probe_mutex);
+}
+
 /*
  * deferred_devs_show() - Show the devices in the deferred probe pending list.
  */
@@ -216,7 +236,8 @@ static int deferred_devs_show(struct seq_file *s, void *data)
 	mutex_lock(&deferred_probe_mutex);
 
 	list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe)
-		seq_printf(s, "%s\n", dev_name(curr->device));
+		seq_printf(s, "%s\t%s", dev_name(curr->device),
+			   curr->device->p->deferred_probe_reason ?: "\n");
 
 	mutex_unlock(&deferred_probe_mutex);
 
@@ -276,7 +297,7 @@ static void deferred_probe_timeout_work_func(struct work_struct *work)
 
 	list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe)
 		dev_info(private->device, "deferred probe pending\n");
-	wake_up(&probe_timeout_waitqueue);
+	wake_up_all(&probe_timeout_waitqueue);
 }
 static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func);
 
@@ -425,10 +446,9 @@ static void driver_sysfs_remove(struct device *dev)
  * Allow manual attachment of a driver to a device.
  * Caller must have already set @dev->driver.
  *
- * Note that this does not modify the bus reference count
- * nor take the bus's rwsem. Please verify those are accounted
- * for before calling this. (It is ok to call with no other effort
- * from a driver's probe() method.)
+ * Note that this does not modify the bus reference count.
+ * Please verify that is accounted for before calling this.
+ * (It is ok to call with no other effort from a driver's probe() method.)
  *
  * This function must be called with the device lock held.
  */
@@ -458,6 +478,18 @@ static void driver_deferred_probe_add_trigger(struct device *dev,
 		driver_deferred_probe_trigger();
 }
 
+static ssize_t state_synced_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	bool val;
+
+	device_lock(dev);
+	val = dev->state_synced;
+	device_unlock(dev);
+	return sprintf(buf, "%u\n", val);
+}
+static DEVICE_ATTR_RO(state_synced);
+
 static int really_probe(struct device *dev, struct device_driver *drv)
 {
 	int ret = -EPROBE_DEFER;
@@ -487,7 +519,8 @@ static int really_probe(struct device *dev, struct device_driver *drv)
 		 drv->bus->name, __func__, drv->name, dev_name(dev));
 	if (!list_empty(&dev->devres_head)) {
 		dev_crit(dev, "Resources present before probing\n");
-		return -EBUSY;
+		ret = -EBUSY;
+		goto done;
 	}
 
 re_probe:
@@ -531,9 +564,16 @@ re_probe:
 		goto dev_groups_failed;
 	}
 
+	if (dev_has_sync_state(dev) &&
+	    device_create_file(dev, &dev_attr_state_synced)) {
+		dev_err(dev, "state_synced sysfs add failed\n");
+		goto dev_sysfs_state_synced_failed;
+	}
+
 	if (test_remove) {
 		test_remove = false;
 
+		device_remove_file(dev, &dev_attr_state_synced);
 		device_remove_groups(dev, drv->dev_groups);
 
 		if (dev->bus->remove)
@@ -563,6 +603,8 @@ re_probe:
 		 drv->bus->name, __func__, dev_name(dev), drv->name);
 	goto done;
 
+dev_sysfs_state_synced_failed:
+	device_remove_groups(dev, drv->dev_groups);
 dev_groups_failed:
 	if (dev->bus->remove)
 		dev->bus->remove(dev);
@@ -607,7 +649,7 @@ pinctrl_bind_failed:
 	ret = 0;
 done:
 	atomic_dec(&probe_count);
-	wake_up(&probe_waitqueue);
+	wake_up_all(&probe_waitqueue);
 	return ret;
 }
 
@@ -843,7 +885,9 @@ static int __device_attach(struct device *dev, bool allow_async)
 	int ret = 0;
 
 	device_lock(dev);
-	if (dev->driver) {
+	if (dev->p->dead) {
+		goto out_unlock;
+	} else if (dev->driver) {
 		if (device_is_bound(dev)) {
 			ret = 1;
 			goto out_unlock;
@@ -1100,6 +1144,7 @@ static void __device_release_driver(struct device *dev, struct device *parent)
 
 		pm_runtime_put_sync(dev);
 
+		device_remove_file(dev, &dev_attr_state_synced);
 		device_remove_groups(dev, drv->dev_groups);
 
 		if (dev->bus && dev->bus->remove)
diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index 0bbb328bd17f..ed615d3b9cf1 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -89,15 +89,23 @@ static struct devres_group * node_to_group(struct devres_node *node)
 	return NULL;
 }
 
+static bool check_dr_size(size_t size, size_t *tot_size)
+{
+	/* We must catch any near-SIZE_MAX cases that could overflow. */
+	if (unlikely(check_add_overflow(sizeof(struct devres),
+					size, tot_size)))
+		return false;
+
+	return true;
+}
+
 static __always_inline struct devres * alloc_dr(dr_release_t release,
 						size_t size, gfp_t gfp, int nid)
 {
 	size_t tot_size;
 	struct devres *dr;
 
-	/* We must catch any near-SIZE_MAX cases that could overflow. */
-	if (unlikely(check_add_overflow(sizeof(struct devres), size,
-					&tot_size)))
+	if (!check_dr_size(size, &tot_size))
 		return NULL;
 
 	dr = kmalloc_node_track_caller(tot_size, gfp, nid);
@@ -807,10 +815,13 @@ static int devm_kmalloc_match(struct device *dev, void *res, void *data)
  * RETURNS:
  * Pointer to allocated memory on success, NULL on failure.
  */
-void * devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
+void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
 {
 	struct devres *dr;
 
+	if (unlikely(!size))
+		return ZERO_SIZE_PTR;
+
 	/* use raw alloc_dr for kmalloc caller tracing */
 	dr = alloc_dr(devm_kmalloc_release, size, gfp, dev_to_node(dev));
 	if (unlikely(!dr))
@@ -942,10 +953,10 @@ void devm_kfree(struct device *dev, const void *p)
 	int rc;
 
 	/*
-	 * Special case: pointer to a string in .rodata returned by
-	 * devm_kstrdup_const().
+	 * Special cases: pointer to a string in .rodata returned by
+	 * devm_kstrdup_const() or NULL/ZERO ptr.
 	 */
-	if (unlikely(is_kernel_rodata((unsigned long)p)))
+	if (unlikely(is_kernel_rodata((unsigned long)p) || ZERO_OR_NULL_PTR(p)))
 		return;
 
 	rc = devres_destroy(dev, devm_kmalloc_release,
diff --git a/drivers/base/driver.c b/drivers/base/driver.c
index 57c68769e157..8c0d33e182fd 100644
--- a/drivers/base/driver.c
+++ b/drivers/base/driver.c
@@ -158,12 +158,12 @@ int driver_register(struct device_driver *drv)
 	if ((drv->bus->probe && drv->probe) ||
 	    (drv->bus->remove && drv->remove) ||
 	    (drv->bus->shutdown && drv->shutdown))
-		printk(KERN_WARNING "Driver '%s' needs updating - please use "
+		pr_warn("Driver '%s' needs updating - please use "
 			"bus_type methods\n", drv->name);
 
 	other = driver_find(drv->name, drv->bus);
 	if (other) {
-		printk(KERN_ERR "Error: Driver '%s' is already registered, "
+		pr_err("Error: Driver '%s' is already registered, "
 			"aborting...\n", drv->name);
 		return -EBUSY;
 	}
diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c
index cdd2c9a9f38a..685edb7dd05a 100644
--- a/drivers/base/firmware_loader/fallback_platform.c
+++ b/drivers/base/firmware_loader/fallback_platform.c
@@ -25,7 +25,10 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags)
 	if (rc)
 		return rc; /* rc == -ENOENT when the fw was not found */
 
-	fw_priv->data = vmalloc(size);
+	if (fw_priv->data && size > fw_priv->allocated_size)
+		return -ENOMEM;
+	if (!fw_priv->data)
+		fw_priv->data = vmalloc(size);
 	if (!fw_priv->data)
 		return -ENOMEM;
 
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
index ca871b13524e..9da0c9d5f538 100644
--- a/drivers/base/firmware_loader/main.c
+++ b/drivers/base/firmware_loader/main.c
@@ -838,12 +838,12 @@ EXPORT_SYMBOL(request_firmware);
  * @name: name of firmware file
  * @device: device for which firmware is being loaded
  *
- * This function is similar in behaviour to request_firmware(), except
- * it doesn't produce warning messages when the file is not found.
- * The sysfs fallback mechanism is enabled if direct filesystem lookup fails,
- * however, however failures to find the firmware file with it are still
- * suppressed. It is therefore up to the driver to check for the return value
- * of this call and to decide when to inform the users of errors.
+ * This function is similar in behaviour to request_firmware(), except it
+ * doesn't produce warning messages when the file is not found. The sysfs
+ * fallback mechanism is enabled if direct filesystem lookup fails. However,
+ * failures to find the firmware file with it are still suppressed. It is
+ * therefore up to the driver to check for the return value of this call and to
+ * decide when to inform the users of errors.
  **/
 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
 			    struct device *device)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 2b09b68b9f78..4db3c660de83 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -50,14 +50,14 @@ int memhp_online_type_from_str(const char *str)
 
 static int sections_per_block;
 
-static inline unsigned long base_memory_block_id(unsigned long section_nr)
+static inline unsigned long memory_block_id(unsigned long section_nr)
 {
 	return section_nr / sections_per_block;
 }
 
 static inline unsigned long pfn_to_block_id(unsigned long pfn)
 {
-	return base_memory_block_id(pfn_to_section_nr(pfn));
+	return memory_block_id(pfn_to_section_nr(pfn));
 }
 
 static inline unsigned long phys_to_block_id(unsigned long phys)
@@ -517,7 +517,7 @@ static struct memory_block *find_memory_block_by_id(unsigned long block_id)
  */
 struct memory_block *find_memory_block(struct mem_section *section)
 {
-	unsigned long block_id = base_memory_block_id(__section_nr(section));
+	unsigned long block_id = memory_block_id(__section_nr(section));
 
 	return find_memory_block_by_id(block_id);
 }
@@ -570,8 +570,7 @@ int register_memory(struct memory_block *memory)
 	return ret;
 }
 
-static int init_memory_block(struct memory_block **memory,
-			     unsigned long block_id, unsigned long state)
+static int init_memory_block(unsigned long block_id, unsigned long state)
 {
 	struct memory_block *mem;
 	unsigned long start_pfn;
@@ -594,14 +593,12 @@ static int init_memory_block(struct memory_block **memory,
 
 	ret = register_memory(mem);
 
-	*memory = mem;
 	return ret;
 }
 
 static int add_memory_block(unsigned long base_section_nr)
 {
 	int section_count = 0;
-	struct memory_block *mem;
 	unsigned long nr;
 
 	for (nr = base_section_nr; nr < base_section_nr + sections_per_block;
@@ -611,7 +608,7 @@ static int add_memory_block(unsigned long base_section_nr)
 
 	if (section_count == 0)
 		return 0;
-	return init_memory_block(&mem, base_memory_block_id(base_section_nr),
+	return init_memory_block(memory_block_id(base_section_nr),
 				 MEM_ONLINE);
 }
 
@@ -647,7 +644,7 @@ int create_memory_block_devices(unsigned long start, unsigned long size)
 		return -EINVAL;
 
 	for (block_id = start_block_id; block_id != end_block_id; block_id++) {
-		ret = init_memory_block(&mem, block_id, MEM_OFFLINE);
+		ret = init_memory_block(block_id, MEM_OFFLINE);
 		if (ret)
 			break;
 	}
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index c0d0a5490ac6..e5d8a0503b4f 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -1019,7 +1019,7 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 	if (len != -ENODEV)
 		return len;
 
-	len = acpi_device_modalias(dev, buf, PAGE_SIZE -1);
+	len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1);
 	if (len != -ENODEV)
 		return len;
 
@@ -1076,13 +1076,37 @@ static ssize_t driver_override_show(struct device *dev,
 }
 static DEVICE_ATTR_RW(driver_override);
 
+static ssize_t numa_node_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%d\n", dev_to_node(dev));
+}
+static DEVICE_ATTR_RO(numa_node);
+
+static umode_t platform_dev_attrs_visible(struct kobject *kobj, struct attribute *a,
+		int n)
+{
+	struct device *dev = container_of(kobj, typeof(*dev), kobj);
+
+	if (a == &dev_attr_numa_node.attr &&
+			dev_to_node(dev) == NUMA_NO_NODE)
+		return 0;
+
+	return a->mode;
+}
 
 static struct attribute *platform_dev_attrs[] = {
 	&dev_attr_modalias.attr,
+	&dev_attr_numa_node.attr,
 	&dev_attr_driver_override.attr,
 	NULL,
 };
-ATTRIBUTE_GROUPS(platform_dev);
+
+static struct attribute_group platform_dev_group = {
+	.attrs = platform_dev_attrs,
+	.is_visible = platform_dev_attrs_visible,
+};
+__ATTRIBUTE_GROUPS(platform_dev);
 
 static int platform_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
diff --git a/drivers/base/swnode.c b/drivers/base/swnode.c
index e5eb27375416..010828fc785b 100644
--- a/drivers/base/swnode.c
+++ b/drivers/base/swnode.c
@@ -761,17 +761,13 @@ EXPORT_SYMBOL_GPL(software_node_register_node_group);
  */
 void software_node_unregister_node_group(const struct software_node **node_group)
 {
-	struct swnode *swnode;
 	unsigned int i;
 
 	if (!node_group)
 		return;
 
-	for (i = 0; node_group[i]; i++) {
-		swnode = software_node_to_swnode(node_group[i]);
-		if (swnode)
-			fwnode_remove_software_node(&swnode->fwnode);
-	}
+	for (i = 0; node_group[i]; i++)
+		software_node_unregister(node_group[i]);
 }
 EXPORT_SYMBOL_GPL(software_node_unregister_node_group);
 
diff --git a/drivers/base/topology.c b/drivers/base/topology.c
index 4e033d4cc0dc..ad8d33c6077b 100644
--- a/drivers/base/topology.c
+++ b/drivers/base/topology.c
@@ -133,7 +133,7 @@ static int topology_remove_dev(unsigned int cpu)
 	return 0;
 }
 
-static int topology_sysfs_init(void)
+static int __init topology_sysfs_init(void)
 {
 	return cpuhp_setup_state(CPUHP_TOPOLOGY_PREPARE,
 				 "base/topology:prepare", topology_add_dev,
diff --git a/drivers/gpu/drm/bridge/lvds-codec.c b/drivers/gpu/drm/bridge/lvds-codec.c
index 24fb1befdfa2..f19d9f7a5db2 100644
--- a/drivers/gpu/drm/bridge/lvds-codec.c
+++ b/drivers/gpu/drm/bridge/lvds-codec.c
@@ -71,13 +71,9 @@ static int lvds_codec_probe(struct platform_device *pdev)
 	lvds_codec->connector_type = (uintptr_t)of_device_get_match_data(dev);
 	lvds_codec->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown",
 							     GPIOD_OUT_HIGH);
-	if (IS_ERR(lvds_codec->powerdown_gpio)) {
-		int err = PTR_ERR(lvds_codec->powerdown_gpio);
-
-		if (err != -EPROBE_DEFER)
-			dev_err(dev, "powerdown GPIO failure: %d\n", err);
-		return err;
-	}
+	if (IS_ERR(lvds_codec->powerdown_gpio))
+		return dev_err_probe(dev, PTR_ERR(lvds_codec->powerdown_gpio),
+				     "powerdown GPIO failure\n");
 
 	/* Locate the panel DT node. */
 	panel_node = of_graph_get_remote_node(dev->of_node, 1, 0);
diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
index 6cd8e012de5d..a282dc962199 100644
--- a/drivers/gpu/drm/bridge/sil-sii8620.c
+++ b/drivers/gpu/drm/bridge/sil-sii8620.c
@@ -2299,10 +2299,9 @@ static int sii8620_probe(struct i2c_client *client,
 	INIT_LIST_HEAD(&ctx->mt_queue);
 
 	ctx->clk_xtal = devm_clk_get(dev, "xtal");
-	if (IS_ERR(ctx->clk_xtal)) {
-		dev_err(dev, "failed to get xtal clock from DT\n");
-		return PTR_ERR(ctx->clk_xtal);
-	}
+	if (IS_ERR(ctx->clk_xtal))
+		return dev_err_probe(dev, PTR_ERR(ctx->clk_xtal),
+				     "failed to get xtal clock from DT\n");
 
 	if (!client->irq) {
 		dev_err(dev, "no irq provided\n");
@@ -2313,16 +2312,14 @@ static int sii8620_probe(struct i2c_client *client,
 					sii8620_irq_thread,
 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 					"sii8620", ctx);
-	if (ret < 0) {
-		dev_err(dev, "failed to install IRQ handler\n");
-		return ret;
-	}
+	if (ret < 0)
+		return dev_err_probe(dev, ret,
+				     "failed to install IRQ handler\n");
 
 	ctx->gpio_reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
-	if (IS_ERR(ctx->gpio_reset)) {
-		dev_err(dev, "failed to get reset gpio from DT\n");
-		return PTR_ERR(ctx->gpio_reset);
-	}
+	if (IS_ERR(ctx->gpio_reset))
+		return dev_err_probe(dev, PTR_ERR(ctx->gpio_reset),
+				     "failed to get reset gpio from DT\n");
 
 	ctx->supplies[0].supply = "cvcc10";
 	ctx->supplies[1].supply = "iovcc18";