Hi Yunfei, kernel test robot noticed the following build warnings: https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Yunfei-Dong/media-mediatek-vcodec-setting-request-complete-before-buffer-done/20241012-144607 base: git://linuxtv.org/media_tree.git master patch link: https://lore.kernel.org/r/20241012064333.27269-2-yunfei.dong%40mediatek.com patch subject: [PATCH v5 1/5] media: mediatek: vcodec: setting request complete before buffer done config: arm-randconfig-r072-20241016 (https://download.01.org/0day-ci/archive/20241019/202410192150.2YkqysDO-lkp@xxxxxxxxx/config) compiler: arm-linux-gnueabi-gcc (GCC) 14.1.0 If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> | Closes: https://lore.kernel.org/r/202410192150.2YkqysDO-lkp@xxxxxxxxx/ smatch warnings: drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c:272 mtk_vdec_stateless_cap_to_disp() warn: variable dereferenced before check 'vb2_v4l2_src' (see line 268) vim +/vb2_v4l2_src +272 drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c 01abf5fbb081c0 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2023-07-29 247 static void mtk_vdec_stateless_cap_to_disp(struct mtk_vcodec_dec_ctx *ctx, int error, 5c46486b8d2760 drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c Yunfei Dong 2024-10-12 248 struct vb2_v4l2_buffer *vb2_v4l2_src) 8cdc3794b2e34b drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2021-08-06 249 { 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 250 struct vb2_v4l2_buffer *vb2_dst; 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 251 enum vb2_buffer_state state; 5c46486b8d2760 drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c Yunfei Dong 2024-10-12 252 struct media_request *src_buf_req; 8cdc3794b2e34b drivers/media/platform/mtk-vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2021-08-06 253 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 254 if (error) 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 255 state = VB2_BUF_STATE_ERROR; 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 256 else 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 257 state = VB2_BUF_STATE_DONE; 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 258 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 259 vb2_dst = v4l2_m2m_dst_buf_remove(ctx->m2m_ctx); d879f770e4d1d5 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-11-17 260 if (vb2_dst) { 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 261 v4l2_m2m_buf_done(vb2_dst, state); 41f03c673cb7b5 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2023-07-29 262 mtk_v4l2_vdec_dbg(2, ctx, "free frame buffer id:%d to done list", 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 263 vb2_dst->vb2_buf.index); d879f770e4d1d5 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-11-17 264 } else { 41f03c673cb7b5 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2023-07-29 265 mtk_v4l2_vdec_err(ctx, "dst buffer is NULL"); d879f770e4d1d5 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-11-17 266 } 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 267 5c46486b8d2760 drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c Yunfei Dong 2024-10-12 @268 src_buf_req = vb2_v4l2_src->vb2_buf.req_obj.req; ^^^^^^^^^^^^^^^ Dereference 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 269 if (src_buf_req) 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 270 v4l2_ctrl_request_complete(src_buf_req, &ctx->ctrl_hdl); 5c46486b8d2760 drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c Yunfei Dong 2024-10-12 271 5c46486b8d2760 drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c Yunfei Dong 2024-10-12 @272 if (vb2_v4l2_src) ^^^^^^^^^^^^ Checked too late 5c46486b8d2760 drivers/media/platform/mediatek/vcodec/decoder/mtk_vcodec_dec_stateless.c Yunfei Dong 2024-10-12 273 v4l2_m2m_buf_done(vb2_v4l2_src, state); 7b182b8d9c8523 drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c Yunfei Dong 2022-05-12 274 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki