drm/amdgpu: Remove dead negative offset check in amdgpu_virt_init_critical_region()

amdgpu_virt_init_critical_region() stores init_hdr_offset as u64.
The subsequent check for init_hdr_offset < 0 is therefore always false.

Drop the unreachable validation and rely on the existing
check_add_overflow() and VRAM end bounds check for offset validation.

This resolves the Smatch warning about comparing an unsigned value
against zero.

drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c:953 amdgpu_virt_init_critical_region() warn: unsigned 'init_hdr_offset' is never less than zero.

Fixes: 07009df6494d ("drm/amdgpu: Introduce SRIOV critical regions v2 during VF init")
Cc: Dan Carpenter <dan.carpenter@linaro.org>
Cc: Ellen Pan <yunru.pan@amd.com>
Cc: Lijo Lazar <lijo.lazar@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Bokun Zhang <bokun.zhang@amd.com>
Reviewed-by: Ellen Pan <yunru.pan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
index 8a8ff8a70d25f8082bfa63b15e6dd195b263eb95..dba7ea16a10d6dfa9f13a0698ce9deec6a422861 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
@@ -950,11 +950,6 @@ int amdgpu_virt_init_critical_region(struct amdgpu_device *adev)
        if (adev->virt.req_init_data_ver != GPU_CRIT_REGION_V2)
                return 0;
 
-       if (init_hdr_offset < 0) {
-               dev_err(adev->dev, "Invalid init header offset\n");
-               return -EINVAL;
-       }
-
        vram_size = RREG32(mmRCC_CONFIG_MEMSIZE);
        if (!vram_size || vram_size == U32_MAX)
                return -EINVAL;