[PATCH 1/2] iommu/arm: smmu: Fix variable shadowing

Michal Orzel posted 2 patches 5 days, 12 hours ago
[PATCH 1/2] iommu/arm: smmu: Fix variable shadowing
Posted by Michal Orzel 5 days, 12 hours ago
Rename 'pdev' to 'pci_dev' in the dev_print_pci() macro to avoid
shadowing local 'pdev' variables at call sites.

Remove the unused 'ret' declaration from arm_smmu_dt_add_device_generic()
where the function-scope 'ret' is sufficient.

Fix shadowing of 'domain' in arm_smmu_assign_dev() by removing the
inner-scope redeclaration, using the function-scope variable instead.

This fixes MISRA C R5.3.

Signed-off-by: Michal Orzel <michal.orzel@amd.com>
---
 xen/drivers/passthrough/arm/smmu.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
index 22d306d0cb80..d63c9015510e 100644
--- a/xen/drivers/passthrough/arm/smmu.c
+++ b/xen/drivers/passthrough/arm/smmu.c
@@ -130,8 +130,8 @@ typedef enum irqreturn irqreturn_t;
         printk(lvl "smmu: %s: " fmt, dev_name((dev)), ## __VA_ARGS__);  \
     else                                                                \
     {                                                                   \
-        struct pci_dev *pdev = dev_to_pci((dev));                       \
-        printk(lvl "smmu: %pp: " fmt, &pdev->sbdf, ## __VA_ARGS__);     \
+        struct pci_dev *pci_dev = dev_to_pci((dev));                    \
+        printk(lvl "smmu: %pp: " fmt, &pci_dev->sbdf, ## __VA_ARGS__);  \
     }                                                                   \
 })
 #endif
@@ -927,7 +927,6 @@ static int arm_smmu_dt_add_device_generic(u8 devfn, struct device *dev)
 	if ( dev_is_pci(dev) )
 	{
 		struct pci_dev *pdev = dev_to_pci(dev);
-		int ret;
 
 		/* Ignore calls for phantom functions */
 		if ( devfn != pdev->devfn )
@@ -2788,7 +2787,7 @@ static int arm_smmu_assign_dev(struct domain *d, u8 devfn,
 		/* dom_io is used as a sentinel for quarantined devices */
 		if ( d == dom_io )
 		{
-			struct iommu_domain *domain = dev_iommu_domain(dev);
+			domain = dev_iommu_domain(dev);
 			if ( !iommu_quarantine )
 				return 0;
 
-- 
2.43.0
Re: [PATCH 1/2] iommu/arm: smmu: Fix variable shadowing
Posted by Stefano Stabellini 5 days, 2 hours ago
On Tue, 7 Apr 2026, Michal Orzel wrote:
> Rename 'pdev' to 'pci_dev' in the dev_print_pci() macro to avoid
> shadowing local 'pdev' variables at call sites.
> 
> Remove the unused 'ret' declaration from arm_smmu_dt_add_device_generic()
> where the function-scope 'ret' is sufficient.
> 
> Fix shadowing of 'domain' in arm_smmu_assign_dev() by removing the
> inner-scope redeclaration, using the function-scope variable instead.
> 
> This fixes MISRA C R5.3.
> 
> Signed-off-by: Michal Orzel <michal.orzel@amd.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
>  xen/drivers/passthrough/arm/smmu.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
> index 22d306d0cb80..d63c9015510e 100644
> --- a/xen/drivers/passthrough/arm/smmu.c
> +++ b/xen/drivers/passthrough/arm/smmu.c
> @@ -130,8 +130,8 @@ typedef enum irqreturn irqreturn_t;
>          printk(lvl "smmu: %s: " fmt, dev_name((dev)), ## __VA_ARGS__);  \
>      else                                                                \
>      {                                                                   \
> -        struct pci_dev *pdev = dev_to_pci((dev));                       \
> -        printk(lvl "smmu: %pp: " fmt, &pdev->sbdf, ## __VA_ARGS__);     \
> +        struct pci_dev *pci_dev = dev_to_pci((dev));                    \
> +        printk(lvl "smmu: %pp: " fmt, &pci_dev->sbdf, ## __VA_ARGS__);  \
>      }                                                                   \
>  })
>  #endif
> @@ -927,7 +927,6 @@ static int arm_smmu_dt_add_device_generic(u8 devfn, struct device *dev)
>  	if ( dev_is_pci(dev) )
>  	{
>  		struct pci_dev *pdev = dev_to_pci(dev);
> -		int ret;
>  
>  		/* Ignore calls for phantom functions */
>  		if ( devfn != pdev->devfn )
> @@ -2788,7 +2787,7 @@ static int arm_smmu_assign_dev(struct domain *d, u8 devfn,
>  		/* dom_io is used as a sentinel for quarantined devices */
>  		if ( d == dom_io )
>  		{
> -			struct iommu_domain *domain = dev_iommu_domain(dev);
> +			domain = dev_iommu_domain(dev);
>  			if ( !iommu_quarantine )
>  				return 0;
>  
> -- 
> 2.43.0
>