Hey Dan, On 10/1/2021 6:50 AM, Dan Carpenter wrote:
On Fri, Oct 01, 2021 at 04:49:12PM +0300, Dan Carpenter wrote:Hello Jeykumar Sankaran, This is a semi-automatic email about new static checker warnings. The patch 25fdd5933e4c: "drm/msm: Add SDM845 DPU support" from Jun 27, 2018, leads to the following Smatch complaint: drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c:422 _dpu_hw_sspp_setup_scaler3() warn: variable dereferenced before check 'ctx->cap->sblk' (see line 421) drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c 420 (void)pe; ^^^^^^^^^
Got it. I'll take care of the null pointer issues, but planning to address the `(void)pe` issue in this patch: https://patchwork.freedesktop.org/patch/456592/
Thanks, Jessica Zhang
You should file a bug report with your compiler devs instead of adding these sorts of statements to your code. This function is used as a function pointer so unused parameters are normal. 421 if (_sspp_subblk_offset(ctx, DPU_SSPP_SCALER_QSEED3, &idx) || !sspp ^^^^^^^^^^^^^^^^^^^^ The _sspp_subblk_offset() dereferenced "ctx" before it is checked and then it also derefereces "ctx->cap->sblk" without checking. 422 || !scaler3_cfg || !ctx || !ctx->cap || !ctx->cap->sblk) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ So these will have already crashed before we reach this point.Same thing later as well. drivers/gpu/drm/msm/disp/dpu1/dpu_hw_sspp.c:591 dpu_hw_sspp_setup_creq_lut() warn: variable dereferenced before check 'ctx->cap' (see line 588) regards, dan carpenter
