From: Nathan Chancellor <nathan@xxxxxxxxxx>
[ Upstream commit c626f3864bbbb28bbe06476b0b497c1330aa4463 ]
In certain randconfigs, clang warns:
drivers/gpu/drm/exynos/exynos_drm_dma.c:121:19: warning: variable
'mapping' is uninitialized when used here [-Wuninitialized]
priv->mapping = mapping;
^~~~~~~
drivers/gpu/drm/exynos/exynos_drm_dma.c:111:16: note: initialize the
variable 'mapping' to silence this warning
void *mapping;
^
= NULL
1 warning generated.
This occurs when CONFIG_EXYNOS_IOMMU is enabled and both
CONFIG_ARM_DMA_USE_IOMMU and CONFIG_IOMMU_DMA are disabled, which makes
the code look like
void *mapping;
if (0)
mapping = arm_iommu_create_mapping()
else if (0)
mapping = iommu_get_domain_for_dev()
...
priv->mapping = mapping;
Add an else branch that initializes mapping to the -ENODEV error pointer
so that there is no more warning and the driver does not change during
runtime.
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Signed-off-by: Inki Dae <inki.dae@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/exynos/exynos_drm_dma.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dma.c b/drivers/gpu/drm/exynos/exynos_drm_dma.c
index 0644936afee2..bf33c3084cb4 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_dma.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_dma.c
@@ -115,6 +115,8 @@ int exynos_drm_register_dma(struct drm_device *drm, struct device *dev,
EXYNOS_DEV_ADDR_START, EXYNOS_DEV_ADDR_SIZE);
else if (IS_ENABLED(CONFIG_IOMMU_DMA))
mapping = iommu_get_domain_for_dev(priv->dma_dev);
+ else
+ mapping = ERR_PTR(-ENODEV);
if (IS_ERR(mapping))
return PTR_ERR(mapping);
--
2.30.2
