2017-06-28 12:02:13

by Joerg Roedel

Subject: [PATCH 1/3] iommu: Return ERR_PTR() values from device_group call-backs

From: Joerg Roedel <[email protected]>

The generic device_group call-backs in iommu.c return NULL
in case of error. Since they are getting ERR_PTR values from
iommu_group_alloc(), just pass them up instead.

Reported-by: Gerald Schaefer <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>
---
drivers/iommu/iommu.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index cf7ca7e..de09e1e 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -915,13 +915,7 @@ static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
*/
struct iommu_group *generic_device_group(struct device *dev)
{
- struct iommu_group *group;
-
- group = iommu_group_alloc();
- if (IS_ERR(group))
- return NULL;
-
- return group;
+ return iommu_group_alloc();
}

/*
@@ -988,11 +982,7 @@ struct iommu_group *pci_device_group(struct device *dev)
return group;

/* No shared group found, allocate new */
- group = iommu_group_alloc();
- if (IS_ERR(group))
- return NULL;
-
- return group;
+ return iommu_group_alloc();
}

/**
--
2.7.4

2017-06-28 12:02:20

by Joerg Roedel

Subject: [PATCH 2/3] iommu/omap: Return ERR_PTR in device_group call-back

From: Joerg Roedel <[email protected]>

Make sure that the device_group callback returns an ERR_PTR
instead of NULL.

Signed-off-by: Joerg Roedel <[email protected]>
---
drivers/iommu/omap-iommu.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 95dfca3..641e035 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -1309,7 +1309,7 @@ static void omap_iommu_remove_device(struct device *dev)
static struct iommu_group *omap_iommu_device_group(struct device *dev)
{
struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
- struct iommu_group *group = NULL;
+ struct iommu_group *group = ERR_PTR(-EINVAL);

if (arch_data->iommu_dev)
group = arch_data->iommu_dev->group;
--
2.7.4

2017-06-28 12:02:30

by Joerg Roedel

Subject: [PATCH 3/3] iommu: Warn once when device_group callback returns NULL

From: Joerg Roedel <[email protected]>

This callback should never return NULL. Print a warning if
that happens so that we notice and can fix it.

Signed-off-by: Joerg Roedel <[email protected]>
---
drivers/iommu/iommu.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index de09e1e..3f6ea16 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -1010,6 +1010,9 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev)
if (ops && ops->device_group)
group = ops->device_group(dev);

+ if (WARN_ON_ONCE(group == NULL))
+ return ERR_PTR(-EINVAL);
+
if (IS_ERR(group))
return group;

--
2.7.4

2017-06-28 15:48:23

by Gerald Schaefer

Subject: Re: [PATCH 1/3] iommu: Return ERR_PTR() values from device_group call-backs

On Wed, 28 Jun 2017 14:00:56 +0200
Joerg Roedel <[email protected]> wrote:

> From: Joerg Roedel <[email protected]>
>
> The generic device_group call-backs in iommu.c return NULL
> in case of error. Since they are getting ERR_PTR values from
> iommu_group_alloc(), just pass them up instead.
>
> Reported-by: Gerald Schaefer <[email protected]>
> Signed-off-by: Joerg Roedel <[email protected]>
> ---

Looks good,
Reviewed-by: Gerald Schaefer <[email protected]>


> drivers/iommu/iommu.c | 14 ++------------
> 1 file changed, 2 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
> index cf7ca7e..de09e1e 100644
> --- a/drivers/iommu/iommu.c
> +++ b/drivers/iommu/iommu.c
> @@ -915,13 +915,7 @@ static int get_pci_alias_or_group(struct pci_dev *pdev, u16 alias, void *opaque)
> */
> struct iommu_group *generic_device_group(struct device *dev)
> {
> - struct iommu_group *group;
> -
> - group = iommu_group_alloc();
> - if (IS_ERR(group))
> - return NULL;
> -
> - return group;
> + return iommu_group_alloc();
> }
>
> /*
> @@ -988,11 +982,7 @@ struct iommu_group *pci_device_group(struct device *dev)
> return group;
>
> /* No shared group found, allocate new */
> - group = iommu_group_alloc();
> - if (IS_ERR(group))
> - return NULL;
> -
> - return group;
> + return iommu_group_alloc();
> }
>
> /**

2017-06-28 16:33:26

by Suman Anna

Subject: Re: [PATCH 2/3] iommu/omap: Return ERR_PTR in device_group call-back

On 06/28/2017 07:00 AM, Joerg Roedel wrote:
> From: Joerg Roedel <[email protected]>
>
> Make sure that the device_group callback returns an ERR_PTR
> instead of NULL.
>
> Signed-off-by: Joerg Roedel <[email protected]>

Thanks for the patch,
Acked-by: Suman Anna <[email protected]>

regards
Suman

> ---
> drivers/iommu/omap-iommu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
> index 95dfca3..641e035 100644
> --- a/drivers/iommu/omap-iommu.c
> +++ b/drivers/iommu/omap-iommu.c
> @@ -1309,7 +1309,7 @@ static void omap_iommu_remove_device(struct device *dev)
> static struct iommu_group *omap_iommu_device_group(struct device *dev)
> {
> struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
> - struct iommu_group *group = NULL;
> + struct iommu_group *group = ERR_PTR(-EINVAL);
>
> if (arch_data->iommu_dev)
> group = arch_data->iommu_dev->group;
>