Re: [PATCH 07/15] iommu/arm-smmu: Fix uninitilized variable warning

Jean-Philippe Brucker
2020-03-16T15:47:22Z

On Tue, Mar 10, 2020 at 10:12:21AM +0100, Joerg Roedel wrote:
> From: Joerg Roedel <jroedel@suse.de>
>
> Some unrelated changes in the iommu code caused a new warning to
> appear in the arm-smmu driver:
>
> CC drivers/iommu/arm-smmu.o
> drivers/iommu/arm-smmu.c: In function 'arm_smmu_add_device':
> drivers/iommu/arm-smmu.c:1441:2: warning: 'smmu' may be used uninitialized in this function [-Wmaybe-uninitialized]
> arm_smmu_rpm_put(smmu);
> ^~~~~~~~~~~~~~~~~~~~~~
>
> The warning is a false positive, but initialize the variable to NULL
> to get rid of it.
>
> Tested-by: Will Deacon <will@kernel.org> # arm-smmu
> Signed-off-by: Joerg Roedel <jroedel@suse.de>

Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>

> ---
> drivers/iommu/arm-smmu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 16c4b87af42b..980aae73b45b 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -1383,7 +1383,7 @@ struct arm_smmu_device *arm_smmu_get_by_fwnode(struct fwnode_handle *fwnode)
>
> static int arm_smmu_add_device(struct device *dev)
> {
> - struct arm_smmu_device *smmu;
> + struct arm_smmu_device *smmu = NULL;
> struct arm_smmu_master_cfg *cfg;
> struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> int i, ret;
> --
> 2.17.1
>