Commit 1e779854 authored by Alan Jenkins's avatar Alan Jenkins Committed by Len Brown
Browse files

eeepc-laptop: fix ordering of init and exit functions 



1. input and backlight devices were registered after acpi notifications
   are enabled.  This left a window where eeepc_hotk_notify() might
   find these devices in an inconsistent (half-initialized) state.

-> Move all device registration into eeepc_hotk_add(), which is called
   before enabling acpi notifications.

2. input and backlight devices were unregistered before acpi
   notifications are disabled.  This left a window where
   eeepc_hotk_notify() might find these devices in an inconsistent
   (half-destroyed) state.

-> Move all device unregistration into eeepc_hotk_remove(), which is
   called after disabling acpi notifications.

3. The acpi driver was not freed if an error occured further down in
   eeepc_laptop_init().

-> The rest of eeepc_laptop_init() has been moved to eeepc_hotk_add(),
   so this is no longer a problem.

4. The acpi driver was unregistered before the platform driver.  This
   left a window where a sysfs access could attempt to read the ehotk
   structure after it had been freed by eeepc_hotk_remove().

-> The acpi driver is now unregistered as the last step in
   eeepc_laptop_exit(), so this is no longer a problem.

Signed-off-by: default avatarAlan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: default avatarCorentin Chary <corentincj@iksaif.net>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 07e84aa9

drivers/platform/x86/eeepc-laptop.c

+59 −61
Original line number Diff line number Diff line
@@ -847,44 +847,6 @@ error_slot: 
	return ret;

}



static int eeepc_hotk_add(struct acpi_device *device)

{

	int result;



	if (!device)

		 return -EINVAL;

	pr_notice(EEEPC_HOTK_NAME "\n");

	ehotk = kzalloc(sizeof(struct eeepc_hotk), GFP_KERNEL);

	if (!ehotk)

		return -ENOMEM;

	ehotk->init_flag = DISABLE_ASL_WLAN | DISABLE_ASL_DISPLAYSWITCH;

	ehotk->handle = device->handle;

	strcpy(acpi_device_name(device), EEEPC_HOTK_DEVICE_NAME);

	strcpy(acpi_device_class(device), EEEPC_HOTK_CLASS);

	device->driver_data = ehotk;

	ehotk->device = device;

	result = eeepc_hotk_check();

	if (result)

		goto ehotk_fail;



	return 0;



 ehotk_fail:

	kfree(ehotk);

	ehotk = NULL;



	return result;

}



static int eeepc_hotk_remove(struct acpi_device *device, int type)

{

	if (!device || !acpi_driver_data(device))

		 return -EINVAL;



	kfree(ehotk);

	return 0;

}



static int eeepc_hotk_resume(struct acpi_device *device)

{

	if (ehotk->wlan_rfkill) {
@@ -1066,19 +1028,6 @@ static void eeepc_hwmon_exit(void) 
	eeepc_hwmon_device = NULL;

}



static void __exit eeepc_laptop_exit(void)

{

	eeepc_backlight_exit();

	eeepc_rfkill_exit();

	eeepc_input_exit();

	eeepc_hwmon_exit();

	acpi_bus_unregister_driver(&eeepc_hotk_driver);

	sysfs_remove_group(&platform_device->dev.kobj,

			   &platform_attribute_group);

	platform_device_unregister(platform_device);

	platform_driver_unregister(&platform_driver);

}



static int eeepc_new_rfkill(struct rfkill **rfkill,

			    const char *name, struct device *dev,

			    enum rfkill_type type, int cm)
@@ -1193,21 +1142,27 @@ static int eeepc_hwmon_init(struct device *dev) 
	return result;

}



static int __init eeepc_laptop_init(void)

static int eeepc_hotk_add(struct acpi_device *device)

{

	struct device *dev;

	int result;



	if (acpi_disabled)

		return -ENODEV;

	result = acpi_bus_register_driver(&eeepc_hotk_driver);

	if (result < 0)

		return result;

	if (!ehotk) {

		acpi_bus_unregister_driver(&eeepc_hotk_driver);

		return -ENODEV;

	}

	if (!device)

		 return -EINVAL;

	pr_notice(EEEPC_HOTK_NAME "\n");

	ehotk = kzalloc(sizeof(struct eeepc_hotk), GFP_KERNEL);

	if (!ehotk)

		return -ENOMEM;

	ehotk->init_flag = DISABLE_ASL_WLAN | DISABLE_ASL_DISPLAYSWITCH;

	ehotk->handle = device->handle;

	strcpy(acpi_device_name(device), EEEPC_HOTK_DEVICE_NAME);

	strcpy(acpi_device_class(device), EEEPC_HOTK_CLASS);

	device->driver_data = ehotk;

	ehotk->device = device;



	result = eeepc_hotk_check();

	if (result)

		goto fail_check;

	eeepc_enable_camera();



	/* Register platform stuff */
@@ -1246,6 +1201,7 @@ static int __init eeepc_laptop_init(void) 
		goto fail_rfkill;



	return 0;



fail_rfkill:

	eeepc_hwmon_exit();

fail_hwmon:
@@ -1261,8 +1217,50 @@ fail_platform_device1: 
	platform_driver_unregister(&platform_driver);

fail_platform_driver:

	eeepc_input_exit();

fail_check:

	kfree(ehotk);



	return result;

}



static int eeepc_hotk_remove(struct acpi_device *device, int type)

{

	if (!device || !acpi_driver_data(device))

		 return -EINVAL;



	eeepc_backlight_exit();

	eeepc_rfkill_exit();

	eeepc_input_exit();

	eeepc_hwmon_exit();

	sysfs_remove_group(&platform_device->dev.kobj,

			   &platform_attribute_group);

	platform_device_unregister(platform_device);

	platform_driver_unregister(&platform_driver);



	kfree(ehotk);

	return 0;

}



static int __init eeepc_laptop_init(void)

{

	int result;



	if (acpi_disabled)

		return -ENODEV;

	result = acpi_bus_register_driver(&eeepc_hotk_driver);

	if (result < 0)

		return result;

	if (!ehotk) {

		acpi_bus_unregister_driver(&eeepc_hotk_driver);

		return -ENODEV;

	}

	return 0;

}



static void __exit eeepc_laptop_exit(void)

{

	acpi_bus_unregister_driver(&eeepc_hotk_driver);

}



module_init(eeepc_laptop_init);

module_exit(eeepc_laptop_exit);

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