From: Sakari Ailus sakari.ailus@linux.intel.com
commit 9054fc6d57e80c27c0b0632966416144f2092c2b upstream.
Printk modifier %pfw is used to print the full path of the device name. This is obtained device by device until a device no longer has a parent.
On ACPI getting the parent fwnode is done by calling acpi_get_parent() which tries to down() a semaphore. But local IRQs are now disabled in vprintk_store() before the mutex is acquired. This is obviously a problem.
Luckily struct device, embedded in struct acpi_device, has a parent field already. Use that field to get the parent instead of relying on acpi_get_parent().
Fixes: 3bd32d6a2ee6 ("lib/vsprintf: Add %pfw conversion specifier for printing fwnode names") Cc: 5.5+ stable@vger.kernel.org # 5.5+ Signed-off-by: Sakari Ailus sakari.ailus@linux.intel.com Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/acpi/property.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-)
--- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -1090,15 +1090,10 @@ struct fwnode_handle *acpi_node_get_pare /* All data nodes have parent pointer so just return that */ return to_acpi_data_node(fwnode)->parent; } else if (is_acpi_device_node(fwnode)) { - acpi_handle handle, parent_handle; + struct device *dev = to_acpi_device_node(fwnode)->dev.parent;
- handle = to_acpi_device_node(fwnode)->handle; - if (ACPI_SUCCESS(acpi_get_parent(handle, &parent_handle))) { - struct acpi_device *adev; - - if (!acpi_bus_get_device(parent_handle, &adev)) - return acpi_fwnode_handle(adev); - } + if (dev) + return acpi_fwnode_handle(to_acpi_device(dev)); }
return NULL;