[PATCH] drm/amd/display: check dc_link before dereferencing

[Melissa Wen]

drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:6683 
amdgpu_dm_connector_funcs_force()
warn: variable dereferenced before check 'dc_link' (see line 6663)

Fixes: 967176179215 ("drm/amd/display: fix null-pointer dereference on edid 
reading")
Reported-by: Dan Carpenter <dan.carpen...@linaro.org>
Signed-off-by: Melissa Wen <m...@igalia.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c 
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 32efce81a5a7..46dd06e8fc7e 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -6653,7 +6653,7 @@ static void amdgpu_dm_connector_funcs_force(struct 
drm_connector *connector)
        struct edid *edid;
        struct i2c_adapter *ddc;
 
-       if (dc_link->aux_mode)
+       if (dc_link && dc_link->aux_mode)
                ddc = &aconnector->dm_dp_aux.aux.ddc;
        else
                ddc = &aconnector->i2c->base;
-- 
2.43.0