[PATCH 3/3] PCI, ACPI: debug print for installation of acpi root bridge's notifier

[Yinghai Lu <yinghai@kernel.org>]

From: Tang Chen <tangchen@cn.fujitsu.com>

acpi_install_notify_handler() could fail. So check the exit status
and give a better debug info.

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Singed-off-by: Yinghai Lu <yinghai@kernel.org>
---
 drivers/acpi/pci_root_hp.c |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/pci_root_hp.c b/drivers/acpi/pci_root_hp.c
index 3edec7f..01e71f6 100644
--- a/drivers/acpi/pci_root_hp.c
+++ b/drivers/acpi/pci_root_hp.c
@@ -282,6 +282,7 @@ static bool acpi_is_root_bridge_object(acpi_handle handle)
 static acpi_status __init
 find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
 {
+	acpi_status status;
 	char objname[64];
 	struct acpi_buffer buffer = { .length = sizeof(objname),
 				      .pointer = objname };
@@ -294,9 +295,14 @@ find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
 
 	acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 
-	acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
-				handle_hotplug_event_root, NULL);
-	printk(KERN_DEBUG "acpi root: %s notify handler installed\n", objname);
+	status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+					handle_hotplug_event_root, NULL);
+	if (ACPI_FAILURE(status))
+		printk(KERN_DEBUG "acpi root: %s notify handler is not installed, exit status: %u\n",
+				  objname, (unsigned int)status);
+	else
+		printk(KERN_DEBUG "acpi root: %s notify handler is installed\n",
+				 objname);
 
 	add_acpi_root_bridge(handle);
 
-- 
1.7.7