Hi Vinod, kernel test robot noticed the following build warnings: url: https://github.com/intel-lab-lkp/linux/commits/Vinod-Govindapillai/drm-i915-fix-the-derating-percentage-for-MTL/20230526-205305 base: git://anongit.freedesktop.org/drm/drm-tip drm-tip patch link: https://lore.kernel.org/r/20230526125055.39886-7-vinod.govindapillai%40intel.com patch subject: [PATCH v8 6/7] drm/i915/mtl: find the best QGV point for the SAGV configuration config: i386-randconfig-m021-20230526 (https://download.01.org/0day-ci/archive/20230528/202305280253.Ab8bRV2w-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-12) 11.3.0 If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <error27@xxxxxxxxx> | Closes: https://lore.kernel.org/r/202305280253.Ab8bRV2w-lkp@xxxxxxxxx/ New smatch warnings: drivers/gpu/drm/i915/display/intel_bw.c:845 mtl_find_qgv_points() error: buffer overflow 'i915->display.bw.max' 6 <= 6 Old smatch warnings: drivers/gpu/drm/i915/display/intel_bw.c:852 mtl_find_qgv_points() error: buffer overflow 'i915->display.bw.max' 6 <= 6 vim +845 drivers/gpu/drm/i915/display/intel_bw.c a10fe26325bd3a Vinod Govindapillai 2023-05-26 806 static int mtl_find_qgv_points(struct drm_i915_private *i915, a10fe26325bd3a Vinod Govindapillai 2023-05-26 807 unsigned int data_rate, a10fe26325bd3a Vinod Govindapillai 2023-05-26 808 unsigned int num_active_planes, a10fe26325bd3a Vinod Govindapillai 2023-05-26 809 const struct intel_bw_state *old_bw_state, a10fe26325bd3a Vinod Govindapillai 2023-05-26 810 struct intel_bw_state *new_bw_state) a10fe26325bd3a Vinod Govindapillai 2023-05-26 811 { a10fe26325bd3a Vinod Govindapillai 2023-05-26 812 unsigned int best_rate = UINT_MAX; a10fe26325bd3a Vinod Govindapillai 2023-05-26 813 unsigned int num_qgv_points = i915->display.bw.max[0].num_qgv_points; a10fe26325bd3a Vinod Govindapillai 2023-05-26 814 unsigned int qgv_peak_bw = 0; a10fe26325bd3a Vinod Govindapillai 2023-05-26 815 int i; a10fe26325bd3a Vinod Govindapillai 2023-05-26 816 int ret; a10fe26325bd3a Vinod Govindapillai 2023-05-26 817 a10fe26325bd3a Vinod Govindapillai 2023-05-26 818 ret = intel_atomic_lock_global_state(&new_bw_state->base); a10fe26325bd3a Vinod Govindapillai 2023-05-26 819 if (ret) a10fe26325bd3a Vinod Govindapillai 2023-05-26 820 return ret; a10fe26325bd3a Vinod Govindapillai 2023-05-26 821 a10fe26325bd3a Vinod Govindapillai 2023-05-26 822 /* a10fe26325bd3a Vinod Govindapillai 2023-05-26 823 * If SAGV cannot be enabled, disable the pcode SAGV by passing all 1's a10fe26325bd3a Vinod Govindapillai 2023-05-26 824 * for qgv peak bw in PM Demand request. So assign UINT_MAX if SAGV is a10fe26325bd3a Vinod Govindapillai 2023-05-26 825 * not enabled. PM Demand code will clamp the value for the register a10fe26325bd3a Vinod Govindapillai 2023-05-26 826 */ a10fe26325bd3a Vinod Govindapillai 2023-05-26 827 if (!intel_can_enable_sagv(i915, new_bw_state)) { a10fe26325bd3a Vinod Govindapillai 2023-05-26 828 new_bw_state->qgv_point_peakbw = UINT_MAX; a10fe26325bd3a Vinod Govindapillai 2023-05-26 829 drm_dbg_kms(&i915->drm, "No SAGV, use UINT_MAX as peak bw."); a10fe26325bd3a Vinod Govindapillai 2023-05-26 830 goto out; a10fe26325bd3a Vinod Govindapillai 2023-05-26 831 } a10fe26325bd3a Vinod Govindapillai 2023-05-26 832 a10fe26325bd3a Vinod Govindapillai 2023-05-26 833 /* a10fe26325bd3a Vinod Govindapillai 2023-05-26 834 * Find the best QGV point by comparing the data_rate with max data rate a10fe26325bd3a Vinod Govindapillai 2023-05-26 835 * offered per plane group a10fe26325bd3a Vinod Govindapillai 2023-05-26 836 */ a10fe26325bd3a Vinod Govindapillai 2023-05-26 837 for (i = 0; i < num_qgv_points; i++) { a10fe26325bd3a Vinod Govindapillai 2023-05-26 838 unsigned int bw_index = a10fe26325bd3a Vinod Govindapillai 2023-05-26 839 tgl_max_bw_index(i915, num_active_planes, i); a10fe26325bd3a Vinod Govindapillai 2023-05-26 840 unsigned int max_data_rate; a10fe26325bd3a Vinod Govindapillai 2023-05-26 841 a10fe26325bd3a Vinod Govindapillai 2023-05-26 842 if (bw_index > ARRAY_SIZE(i915->display.bw.max)) Should be >= ARRAY_SIZE() a10fe26325bd3a Vinod Govindapillai 2023-05-26 843 continue; a10fe26325bd3a Vinod Govindapillai 2023-05-26 844 a10fe26325bd3a Vinod Govindapillai 2023-05-26 @845 max_data_rate = i915->display.bw.max[bw_index].deratedbw[i]; a10fe26325bd3a Vinod Govindapillai 2023-05-26 846 a10fe26325bd3a Vinod Govindapillai 2023-05-26 847 if (max_data_rate < data_rate) a10fe26325bd3a Vinod Govindapillai 2023-05-26 848 continue; a10fe26325bd3a Vinod Govindapillai 2023-05-26 849 a10fe26325bd3a Vinod Govindapillai 2023-05-26 850 if (max_data_rate - data_rate < best_rate) { a10fe26325bd3a Vinod Govindapillai 2023-05-26 851 best_rate = max_data_rate - data_rate; a10fe26325bd3a Vinod Govindapillai 2023-05-26 852 qgv_peak_bw = i915->display.bw.max[bw_index].peakbw[i]; a10fe26325bd3a Vinod Govindapillai 2023-05-26 853 } a10fe26325bd3a Vinod Govindapillai 2023-05-26 854 a10fe26325bd3a Vinod Govindapillai 2023-05-26 855 drm_dbg_kms(&i915->drm, "QGV point %d: max bw %d required %d qgv_peak_bw: %d\n", a10fe26325bd3a Vinod Govindapillai 2023-05-26 856 i, max_data_rate, data_rate, qgv_peak_bw); a10fe26325bd3a Vinod Govindapillai 2023-05-26 857 } a10fe26325bd3a Vinod Govindapillai 2023-05-26 858 a10fe26325bd3a Vinod Govindapillai 2023-05-26 859 drm_dbg_kms(&i915->drm, "Matching peaks QGV bw: %d for required data rate: %d\n", a10fe26325bd3a Vinod Govindapillai 2023-05-26 860 qgv_peak_bw, data_rate); a10fe26325bd3a Vinod Govindapillai 2023-05-26 861 a10fe26325bd3a Vinod Govindapillai 2023-05-26 862 /* a10fe26325bd3a Vinod Govindapillai 2023-05-26 863 * The display configuration cannot be supported if no QGV point a10fe26325bd3a Vinod Govindapillai 2023-05-26 864 * satisfying the required data rate is found a10fe26325bd3a Vinod Govindapillai 2023-05-26 865 */ a10fe26325bd3a Vinod Govindapillai 2023-05-26 866 if (qgv_peak_bw == 0) { a10fe26325bd3a Vinod Govindapillai 2023-05-26 867 drm_dbg_kms(&i915->drm, "No QGV points for bw %d for display configuration(%d active planes).\n", a10fe26325bd3a Vinod Govindapillai 2023-05-26 868 data_rate, num_active_planes); a10fe26325bd3a Vinod Govindapillai 2023-05-26 869 return -EINVAL; a10fe26325bd3a Vinod Govindapillai 2023-05-26 870 } a10fe26325bd3a Vinod Govindapillai 2023-05-26 871 a10fe26325bd3a Vinod Govindapillai 2023-05-26 872 /* MTL PM DEMAND expects QGV BW parameter in multiples of 100 mbps */ a10fe26325bd3a Vinod Govindapillai 2023-05-26 873 new_bw_state->qgv_point_peakbw = DIV_ROUND_CLOSEST(qgv_peak_bw, 100); a10fe26325bd3a Vinod Govindapillai 2023-05-26 874 a10fe26325bd3a Vinod Govindapillai 2023-05-26 875 out: a10fe26325bd3a Vinod Govindapillai 2023-05-26 876 if (new_bw_state->qgv_point_peakbw != old_bw_state->qgv_point_peakbw) { a10fe26325bd3a Vinod Govindapillai 2023-05-26 877 ret = intel_atomic_serialize_global_state(&new_bw_state->base); a10fe26325bd3a Vinod Govindapillai 2023-05-26 878 if (ret) a10fe26325bd3a Vinod Govindapillai 2023-05-26 879 return ret; a10fe26325bd3a Vinod Govindapillai 2023-05-26 880 } a10fe26325bd3a Vinod Govindapillai 2023-05-26 881 a10fe26325bd3a Vinod Govindapillai 2023-05-26 882 return 0; a10fe26325bd3a Vinod Govindapillai 2023-05-26 883 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
