From 9090589d87506c578ea1523ffd7ae7fd9424fb28 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Tue, 7 Apr 2009 10:24:29 +0800 Subject: ACPI: convert acpi_device_lock spinlock to mutex Convert acpi_device_lock to a mutex to avoid a potential race upon access to /proc/acpi/wakeup Delete the lock entirely in wakeup.c since it is not necessary (and can not sleep) Found-by: Linus Torvalds Signed-off-by: Shaohua Li Signed-off-by: Len Brown --- drivers/acpi/scan.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 20c23c049207..e63f2febad84 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -24,7 +24,7 @@ extern struct acpi_device *acpi_root; static LIST_HEAD(acpi_device_list); static LIST_HEAD(acpi_bus_id_list); -DEFINE_SPINLOCK(acpi_device_lock); +DEFINE_MUTEX(acpi_device_lock); LIST_HEAD(acpi_wakeup_device_list); struct acpi_device_bus_id{ @@ -500,7 +500,7 @@ static int acpi_device_register(struct acpi_device *device, return -ENOMEM; } - spin_lock(&acpi_device_lock); + mutex_lock(&acpi_device_lock); /* * Find suitable bus_id and instance number in acpi_bus_id_list * If failed, create one and link it into acpi_bus_id_list @@ -528,7 +528,7 @@ static int acpi_device_register(struct acpi_device *device, list_add_tail(&device->g_list, &acpi_device_list); if (device->wakeup.flags.valid) list_add_tail(&device->wakeup_list, &acpi_wakeup_device_list); - spin_unlock(&acpi_device_lock); + mutex_unlock(&acpi_device_lock); if (device->parent) device->dev.parent = &parent->dev; @@ -549,20 +549,20 @@ static int acpi_device_register(struct acpi_device *device, device->removal_type = ACPI_BUS_REMOVAL_NORMAL; return 0; end: - spin_lock(&acpi_device_lock); + mutex_lock(&acpi_device_lock); if (device->parent) { list_del(&device->node); list_del(&device->g_list); } else list_del(&device->g_list); list_del(&device->wakeup_list); - spin_unlock(&acpi_device_lock); + mutex_unlock(&acpi_device_lock); return result; } static void acpi_device_unregister(struct acpi_device *device, int type) { - spin_lock(&acpi_device_lock); + mutex_lock(&acpi_device_lock); if (device->parent) { list_del(&device->node); list_del(&device->g_list); @@ -570,7 +570,7 @@ static void acpi_device_unregister(struct acpi_device *device, int type) list_del(&device->g_list); list_del(&device->wakeup_list); - spin_unlock(&acpi_device_lock); + mutex_unlock(&acpi_device_lock); acpi_detach_data(device->handle, acpi_bus_data_handler); -- cgit v1.2.1