tree: https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x8... review-hans head: 0f1f7f22f384f34b2f0800a3734aa0fc83eafff2 commit: c167b9c7e3d6131b4a4865c112a3dbc86d2e997d [10/93] platform/surface: Add Surface Aggregator subsystem config: i386-randconfig-s002-20210211 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-215-g0fb77bb6-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x8... git remote add linux-platform-drivers-x86 https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x8... git fetch --no-tags linux-platform-drivers-x86 review-hans git checkout c167b9c7e3d6131b4a4865c112a3dbc86d2e997d # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; "sparse warnings: (new ones prefixed by >>)" vim +1413 drivers/platform/surface/aggregator/ssh_packet_layer.c 1343 1344 static size_t ssh_ptl_rx_eval(struct ssh_ptl *ptl, struct ssam_span *source) 1345 { 1346 struct ssh_frame *frame; 1347 struct ssam_span payload; 1348 struct ssam_span aligned; 1349 bool syn_found; 1350 int status; 1351 1352 /* Find SYN. */ 1353 syn_found = sshp_find_syn(source, &aligned); 1354 1355 if (unlikely(aligned.ptr - source->ptr) > 0) { 1356 ptl_warn(ptl, "rx: parser: invalid start of frame, skipping\n"); 1357 1358 /* 1359 * Notes: 1360 * - This might send multiple NAKs in case the communication 1361 * starts with an invalid SYN and is broken down into multiple 1362 * pieces. This should generally be handled fine, we just 1363 * might receive duplicate data in this case, which is 1364 * detected when handling data frames. 1365 * - This path will also be executed on invalid CRCs: When an 1366 * invalid CRC is encountered, the code below will skip data 1367 * until directly after the SYN. This causes the search for 1368 * the next SYN, which is generally not placed directly after 1369 * the last one. 1370 * 1371 * Open question: Should we send this in case of invalid 1372 * payload CRCs if the frame-type is non-sequential (current 1373 * implementation) or should we drop that frame without 1374 * telling the EC? 1375 */ 1376 ssh_ptl_send_nak(ptl); 1377 } 1378 1379 if (unlikely(!syn_found)) 1380 return aligned.ptr - source->ptr; 1381 1382 /* Parse and validate frame. */ 1383 status = sshp_parse_frame(&ptl->serdev->dev, &aligned, &frame, &payload, 1384 SSH_PTL_RX_BUF_LEN); 1385 if (status) /* Invalid frame: skip to next SYN. */ 1386 return aligned.ptr - source->ptr + sizeof(u16); 1387 if (!frame) /* Not enough data. */ 1388 return aligned.ptr - source->ptr; 1389 1390 switch (frame->type) { 1391 case SSH_FRAME_TYPE_ACK: 1392 ssh_ptl_acknowledge(ptl, frame->seq); 1393 break; 1394 1395 case SSH_FRAME_TYPE_NAK: 1396 ssh_ptl_resubmit_pending(ptl); 1397 break; 1398 1399 case SSH_FRAME_TYPE_DATA_SEQ: 1400 ssh_ptl_send_ack(ptl, frame->seq); 1401 fallthrough; 1402 1403 case SSH_FRAME_TYPE_DATA_NSQ: 1404 ssh_ptl_rx_dataframe(ptl, frame, &payload); 1405 break; 1406 1407 default: 1408 ptl_warn(ptl, "ptl: received frame with unknown type %#04x\n", 1409 frame->type); 1410 break; 1411 } 1412 1414 } 1415 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org