iommu: Make iommu_bus_notifier return NOTIFY_DONE rather than error code

In iommu_bus_notifier(), when action is
BUS_NOTIFY_ADD_DEVICE, it will return 'ops->add_device(dev)'
directly. But ops->add_device will return ERR_VAL, such as
-ENODEV. These value will make notifier_call_chain() not to
traverse the remain nodes in struct notifier_block list.

This patch revises iommu_bus_notifier() to return
NOTIFY_DONE when some errors happened in ops->add_device().

Signed-off-by: zhichang.yuan <yuanzhichang@hisilicon.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 6 insertions, 2 deletions

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 8ea14f41a979..9170fd498f46 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1082,8 +1082,12 @@ static int iommu_bus_notifier(struct notifier_block *nb,
          * result in ADD/DEL notifiers to group->notifier
          */
         if (action == BUS_NOTIFY_ADD_DEVICE) {
-                if (ops->add_device)
-                        return ops->add_device(dev);
+                if (ops->add_device) {
+                        int ret;
+
+                        ret = ops->add_device(dev);
+                        return (ret) ? NOTIFY_DONE : NOTIFY_OK;
+                }
         } else if (action == BUS_NOTIFY_REMOVED_DEVICE) {
                 if (ops->remove_device && dev->iommu_group) {
                         ops->remove_device(dev);