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
