Driver core fixes for 6.0-rc4

Here are some small driver core fixes for some oft-reported problems in
 6.0-rc1.  They include:
   - a bunch of reverts to handle driver_deferred_probe_check_state()
     problems that were part of the 6.0-rc1 merge.
   - firmware_loader bugfixes now that the code is being properly tested
     and used by others
   - arch_topology fix
   - deferred driver probe bugfix to solve a long-suffering amba bus
     problem that many people have reported.
 
 All of these have been in linux-next for a while with no reported
 problems.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are some small driver core fixes for some oft-reported problems
  in 6.0-rc1.  They include:

   - a bunch of reverts to handle driver_deferred_probe_check_state()
     problems that were part of the 6.0-rc1 merge.

   - firmware_loader bugfixes now that the code is being properly tested
     and used by others

   - arch_topology fix

   - deferred driver probe bugfix to solve a long-suffering amba bus
     problem that many people have reported.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  firmware_loader: Fix memory leak in firmware upload
  firmware_loader: Fix use-after-free during unregister
  arch_topology: Silence early cacheinfo errors when non-existent
  driver core: Don't probe devices after bus_type.match() probe deferral
  Revert "iommu/of: Delete usage of driver_deferred_probe_check_state()"
  Revert "PM: domains: Delete usage of driver_deferred_probe_check_state()"
  Revert "net: mdio: Delete usage of driver_deferred_probe_check_state()"
  Revert "driver core: Delete driver_deferred_probe_check_state()"

drivers/base/arch_topology.c

@@ -735,7 +735,7 @@ void update_siblings_masks(unsigned int cpuid)
 	int cpu, ret;
 
 	ret = detect_cache_attributes(cpuid);
-	if (ret)
+	if (ret && ret != -ENOENT)
 		pr_info("Early cacheinfo failed, ret = %d\n", ret);
 
 	/* update core and thread sibling masks */

drivers/base/dd.c

@@ -274,12 +274,42 @@ static int __init deferred_probe_timeout_setup(char *str)
 }
 __setup("deferred_probe_timeout=", deferred_probe_timeout_setup);
 
+/**
+ * driver_deferred_probe_check_state() - Check deferred probe state
+ * @dev: device to check
+ *
+ * Return:
+ * * -ENODEV if initcalls have completed and modules are disabled.
+ * * -ETIMEDOUT if the deferred probe timeout was set and has expired
+ *   and modules are enabled.
+ * * -EPROBE_DEFER in other cases.
+ *
+ * Drivers or subsystems can opt-in to calling this function instead of directly
+ * returning -EPROBE_DEFER.
+ */
+int driver_deferred_probe_check_state(struct device *dev)
+{
+	if (!IS_ENABLED(CONFIG_MODULES) && initcalls_done) {
+		dev_warn(dev, "ignoring dependency for device, assuming no driver\n");
+		return -ENODEV;
+	}
+
+	if (!driver_deferred_probe_timeout && initcalls_done) {
+		dev_warn(dev, "deferred probe timeout, ignoring dependency\n");
+		return -ETIMEDOUT;
+	}
+
+	return -EPROBE_DEFER;
+}
+EXPORT_SYMBOL_GPL(driver_deferred_probe_check_state);
+
 static void deferred_probe_timeout_work_func(struct work_struct *work)
 {
 	struct device_private *p;
 
 	fw_devlink_drivers_done();
 
+	driver_deferred_probe_timeout = 0;
 	driver_deferred_probe_trigger();
 	flush_work(&deferred_probe_work);
 
@@ -881,6 +911,11 @@ static int __device_attach_driver(struct device_driver *drv, void *_data)
 		dev_dbg(dev, "Device match requests probe deferral\n");
 		dev->can_match = true;
 		driver_deferred_probe_add(dev);
+		/*
+		 * Device can't match with a driver right now, so don't attempt
+		 * to match or bind with other drivers on the bus.
+		 */
+		return ret;
 	} else if (ret < 0) {
 		dev_dbg(dev, "Bus failed to match device: %d\n", ret);
 		return ret;
@@ -1120,6 +1155,11 @@ static int __driver_attach(struct device *dev, void *data)
 		dev_dbg(dev, "Device match requests probe deferral\n");
 		dev->can_match = true;
 		driver_deferred_probe_add(dev);
+		/*
+		 * Driver could not match with device, but may match with
+		 * another device on the bus.
+		 */
+		return 0;
 	} else if (ret < 0) {
 		dev_dbg(dev, "Bus failed to match device: %d\n", ret);
 		return ret;

drivers/base/firmware_loader/sysfs.c

@@ -93,10 +93,9 @@ static void fw_dev_release(struct device *dev)
 {
 	struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev);
 
-	if (fw_sysfs->fw_upload_priv) {
-		free_fw_priv(fw_sysfs->fw_priv);
-		kfree(fw_sysfs->fw_upload_priv);
-	}
+	if (fw_sysfs->fw_upload_priv)
+		fw_upload_free(fw_sysfs);
+
 	kfree(fw_sysfs);
 }
 

drivers/base/firmware_loader/sysfs.h

@@ -106,12 +106,17 @@ extern struct device_attribute dev_attr_cancel;
 extern struct device_attribute dev_attr_remaining_size;
 
 int fw_upload_start(struct fw_sysfs *fw_sysfs);
+void fw_upload_free(struct fw_sysfs *fw_sysfs);
 umode_t fw_upload_is_visible(struct kobject *kobj, struct attribute *attr, int n);
 #else
 static inline int fw_upload_start(struct fw_sysfs *fw_sysfs)
 {
 	return 0;
 }
+
+static inline void fw_upload_free(struct fw_sysfs *fw_sysfs)
+{
+}
 #endif
 
 #endif /* __FIRMWARE_SYSFS_H */

drivers/base/firmware_loader/sysfs_upload.c

@@ -264,6 +264,15 @@ int fw_upload_start(struct fw_sysfs *fw_sysfs)
 	return 0;
 }
 
+void fw_upload_free(struct fw_sysfs *fw_sysfs)
+{
+	struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv;
+
+	free_fw_priv(fw_sysfs->fw_priv);
+	kfree(fw_upload_priv->fw_upload);
+	kfree(fw_upload_priv);
+}
+
 /**
  * firmware_upload_register() - register for the firmware upload sysfs API
  * @module: kernel module of this device
@@ -377,6 +386,7 @@ void firmware_upload_unregister(struct fw_upload *fw_upload)
 {
 	struct fw_sysfs *fw_sysfs = fw_upload->priv;
 	struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv;
+	struct module *module = fw_upload_priv->module;
 
 	mutex_lock(&fw_upload_priv->lock);
 	if (fw_upload_priv->progress == FW_UPLOAD_PROG_IDLE) {
@@ -392,6 +402,6 @@ void firmware_upload_unregister(struct fw_upload *fw_upload)
 
 unregister:
 	device_unregister(&fw_sysfs->dev);
-	module_put(fw_upload_priv->module);
+	module_put(module);
 }
 EXPORT_SYMBOL_GPL(firmware_upload_unregister);

drivers/base/power/domain.c

@@ -2733,7 +2733,7 @@ static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
 		mutex_unlock(&gpd_list_lock);
 		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
 			__func__, PTR_ERR(pd));
-		return -ENODEV;
+		return driver_deferred_probe_check_state(base_dev);
 	}
 
 	dev_dbg(dev, "adding to PM domain %s\n", pd->name);

drivers/iommu/of_iommu.c

@@ -40,7 +40,7 @@ static int of_iommu_xlate(struct device *dev,
 	 * a proper probe-ordering dependency mechanism in future.
 	 */
 	if (!ops)
-		return -ENODEV;
+		return driver_deferred_probe_check_state(dev);
 
 	if (!try_module_get(ops->owner))
 		return -ENODEV;

drivers/net/mdio/fwnode_mdio.c

@@ -47,7 +47,9 @@ int fwnode_mdiobus_phy_device_register(struct mii_bus *mdio,
 	 * just fall back to poll mode
 	 */
 	if (rc == -EPROBE_DEFER)
-		rc = -ENODEV;
+		rc = driver_deferred_probe_check_state(&phy->mdio.dev);
+	if (rc == -EPROBE_DEFER)
+		return rc;
 
 	if (rc > 0) {
 		phy->irq = rc;

include/linux/device/driver.h

@@ -242,6 +242,7 @@ driver_find_device_by_acpi_dev(struct device_driver *drv, const void *adev)
 
 extern int driver_deferred_probe_timeout;
 void driver_deferred_probe_add(struct device *dev);
+int driver_deferred_probe_check_state(struct device *dev);
 void driver_init(void);
 
 /**