From: Rafael J. Wysocki <rjw@xxxxxxx> Some ACPI BIOSes define _PRW for the root object which causes acpi_setup_gpe_for_wake() to crash when trying to dereference the bogus device_node pointer. Avoid the crash by checking if wake_device is not the root object before attempting to set up the "implicit notify" mechanism for it. Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> --- drivers/acpi/acpica/evxfgpe.c | 49 ++++++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 23 deletions(-) Index: linux-2.6/drivers/acpi/acpica/evxfgpe.c =================================================================== --- linux-2.6.orig/drivers/acpi/acpica/evxfgpe.c +++ linux-2.6/drivers/acpi/acpica/evxfgpe.c @@ -212,37 +212,40 @@ acpi_setup_gpe_for_wake(acpi_handle wake return_ACPI_STATUS(AE_BAD_PARAMETER); } - /* Validate wake_device is of type Device */ - - device_node = ACPI_CAST_PTR(struct acpi_namespace_node, wake_device); - if (device_node->type != ACPI_TYPE_DEVICE) { - return_ACPI_STATUS(AE_BAD_PARAMETER); - } - flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock); /* Ensure that we have a valid GPE number */ gpe_event_info = acpi_ev_get_gpe_event_info(gpe_device, gpe_number); - if (gpe_event_info) { - /* - * If there is no method or handler for this GPE, then the - * wake_device will be notified whenever this GPE fires (aka - * "implicit notify") Note: The GPE is assumed to be - * level-triggered (for windows compatibility). - */ - if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) == - ACPI_GPE_DISPATCH_NONE) { - gpe_event_info->flags = - (ACPI_GPE_DISPATCH_NOTIFY | - ACPI_GPE_LEVEL_TRIGGERED); - gpe_event_info->dispatch.device_node = device_node; - } + if (!gpe_event_info) { + goto unlock_and_exit; + } - gpe_event_info->flags |= ACPI_GPE_CAN_WAKE; - status = AE_OK; + /* + * If there is no method or handler for this GPE, then the + * wake_device will be notified whenever this GPE fires (aka + * "implicit notify") Note: The GPE is assumed to be + * level-triggered (for windows compatibility). + */ + if (((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) == + ACPI_GPE_DISPATCH_NONE) && (wake_device != ACPI_ROOT_OBJECT)) { + + /* Validate wake_device is of type Device */ + + device_node = ACPI_CAST_PTR(struct acpi_namespace_node, + wake_device); + if (device_node->type != ACPI_TYPE_DEVICE) { + goto unlock_and_exit; + } + gpe_event_info->flags = (ACPI_GPE_DISPATCH_NOTIFY | + ACPI_GPE_LEVEL_TRIGGERED); + gpe_event_info->dispatch.device_node = device_node; } + gpe_event_info->flags |= ACPI_GPE_CAN_WAKE; + status = AE_OK; + + unlock_and_exit: acpi_os_release_lock(acpi_gbl_gpe_lock, flags); return_ACPI_STATUS(status); } -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html