From 1e7798547fe6920ae27fb92c9202353e9e4c55db Mon Sep 17 00:00:00 2001 From: Alan Jenkins Date: Fri, 28 Aug 2009 12:56:35 +0000 Subject: [PATCH] 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: Alan Jenkins Signed-off-by: Corentin Chary Signed-off-by: Len Brown --- drivers/platform/x86/eeepc-laptop.c | 120 ++++++++++++++-------------- 1 file changed, 59 insertions(+), 61 deletions(-) diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c index 8dd86f73b844..cf47d1cd1a34 100644 --- a/drivers/platform/x86/eeepc-laptop.c +++ b/drivers/platform/x86/eeepc-laptop.c @@ -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); -- 2.34.1