2017-04-18 12:21:21

by zhichang.yuan

Subject: [PATCH] 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
heppened in ops->add_device().

Signed-off-by: zhichang.yuan <[email protected]>
---
drivers/iommu/iommu.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 3b67144..2d32911 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1083,8 +1083,12 @@ 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);
--
1.9.1

2017-04-20 14:44:05

by Joerg Roedel

Subject: Re: [PATCH] iommu: make iommu_bus_notifier return NOTIFY_DONE rather than error code

On Tue, Apr 18, 2017 at 08:51:48PM +0800, zhichang.yuan wrote:
> 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
> heppened in ops->add_device().
>
> Signed-off-by: zhichang.yuan <[email protected]>

Applied, thanks.