drm/amd/amdgpu/amdgpu_ttm: Handle return NULL error from ioremap_nocache

Here, If ioremap_nocache will fail. It will return NULL.
Kernel can run into a NULL-pointer dereference.
This error check will avoid NULL pointer dereference.

Reviewed-by: Christian König <[email protected]>
Signed-off-by: Arvind Yadav <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 10e9b690676e406fd2c5fd6ef3c5400d0bf093d9..1154b0a8881d6f9d70194f971c7fb04cffc2d6a7 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -548,6 +548,8 @@ static int amdgpu_ttm_io_mem_reserve(struct ttm_bo_device *bdev, struct ttm_mem_
                        mem->bus.addr =
                                ioremap_nocache(mem->bus.base + mem->bus.offset,
                                                mem->bus.size);
+               if (!mem->bus.addr)
+                       return -ENOMEM;
 
                /*
                 * Alpha: Use just the bus offset plus