tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 99613159ad749543621da8238acf1a122880144e commit: e2558f0f84d85bfe2407b91d57798f133d8ad32a habanalabs: prevent wait if CS in multi-CS list completed config: s390-randconfig-m031-20220117 (https://download.01.org/0day-ci/archive/20220119/202201190048.qRDA3uFx-lk...) compiler: s390-linux-gcc (GCC) 11.2.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: drivers/misc/habanalabs/common/command_submission.c:2457 hl_cs_poll_fences() error: we previously assumed 'fence' could be null (see line 2430) vim +/fence +2457 drivers/misc/habanalabs/common/command_submission.c e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2383 static int hl_cs_poll_fences(struct multi_cs_data *mcs_data, struct multi_cs_completion *mcs_compl) 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2384 { 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2385 struct hl_fence **fence_ptr = mcs_data->fence_arr; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2386 struct hl_device *hdev = mcs_data->ctx->hdev; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2387 int i, rc, arr_len = mcs_data->arr_len; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2388 u64 *seq_arr = mcs_data->seq_arr; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2389 ktime_t max_ktime, first_cs_time; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2390 enum hl_cs_wait_status status; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2391 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2392 memset(fence_ptr, 0, arr_len * sizeof(*fence_ptr)); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2393 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2394 /* get all fences under the same lock */ 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2395 rc = hl_ctx_get_fences(mcs_data->ctx, seq_arr, fence_ptr, arr_len); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2396 if (rc) 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2397 return rc; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2398 e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2399 /* e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2400 * re-initialize the completion here to handle 2 possible cases: e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2401 * 1. CS will complete the multi-CS prior clearing the completion. in which e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2402 * case the fence iteration is guaranteed to catch the CS completion. e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2403 * 2. the completion will occur after re-init of the completion. e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2404 * in which case we will wake up immediately in wait_for_completion. e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2405 */ e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2406 reinit_completion(&mcs_compl->completion); e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2407 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2408 /* 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2409 * set to maximum time to verify timestamp is valid: if at the end 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2410 * this value is maintained- no timestamp was updated 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2411 */ 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2412 max_ktime = ktime_set(KTIME_SEC_MAX, 0); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2413 first_cs_time = max_ktime; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2414 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2415 for (i = 0; i < arr_len; i++, fence_ptr++) { 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2416 struct hl_fence *fence = *fence_ptr; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2417 e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2418 /* e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2419 * In order to prevent case where we wait until timeout even though a CS associated e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2420 * with the multi-CS actually completed we do things in the below order: e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2421 * 1. for each fence set it's QID map in the multi-CS completion QID map. This way e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2422 * any CS can, potentially, complete the multi CS for the specific QID (note e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2423 * that once completion is initialized, calling complete* and then wait on the e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2424 * completion will cause it to return at once) e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2425 * 2. only after allowing multi-CS completion for the specific QID we check whether e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2426 * the specific CS already completed (and thus the wait for completion part will e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2427 * be skipped). if the CS not completed it is guaranteed that completing CS will e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2428 * wake up the completion. e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2429 */ e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 @2430 if (fence) ^^^^^ e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2431 mcs_compl->stream_master_qid_map |= fence->stream_master_qid_map; e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2432 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2433 /* 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2434 * function won't sleep as it is called with timeout 0 (i.e. 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2435 * poll the fence) 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2436 */ 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2437 rc = hl_wait_for_fence(mcs_data->ctx, seq_arr[i], fence, 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2438 &status, 0, NULL); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2439 if (rc) { 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2440 dev_err(hdev->dev, 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2441 "wait_for_fence error :%d for CS seq %llu\n", 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2442 rc, seq_arr[i]); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2443 break; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2444 } 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2445 b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2446 switch (status) { b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2447 case CS_WAIT_STATUS_BUSY: e2558f0f84d85b drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-12-07 2448 /* CS did not finished, QID to wait on already stored */ b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2449 break; b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2450 case CS_WAIT_STATUS_COMPLETED: ea6eb91c09cd4f drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-03 2451 /* ea6eb91c09cd4f drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-03 2452 * Using mcs_handling_done to avoid possibility of mcs_data ea6eb91c09cd4f drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-03 2453 * returns to user indicating CS completed before it finished ea6eb91c09cd4f drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-03 2454 * all of its mcs handling, to avoid race the next time the ea6eb91c09cd4f drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-03 2455 * user waits for mcs. ea6eb91c09cd4f drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-03 2456 */ b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 @2457 if (!fence->mcs_handling_done) ^^^^^^^ Unchecked derereference b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2458 break; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2459 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2460 mcs_data->completion_bitmap |= BIT(i); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2461 /* b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2462 * For all completed CSs we take the earliest timestamp. b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2463 * For this we have to validate that the timestamp is b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2464 * earliest of all timestamps so far. 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2465 */ b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2466 if (mcs_data->update_ts && b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2467 (ktime_compare(fence->timestamp, first_cs_time) < 0)) b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2468 first_cs_time = fence->timestamp; b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2469 break; b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2470 case CS_WAIT_STATUS_GONE: 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2471 mcs_data->update_ts = false; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2472 mcs_data->gone_cs = true; b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2473 /* b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2474 * It is possible to get an old sequence numbers from user b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2475 * which related to already completed CSs and their fences b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2476 * already gone. In this case, CS set as completed but b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2477 * no need to consider its QID for mcs completion. b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2478 */ b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2479 mcs_data->completion_bitmap |= BIT(i); b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2480 break; b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2481 default: b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2482 dev_err(hdev->dev, "Invalid fence status\n"); b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2483 return -EINVAL; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2484 } b2faac3887df87 drivers/misc/habanalabs/common/command_submission.c Dani Liberman 2021-10-12 2485 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2486 } 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2487 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2488 hl_fences_put(mcs_data->fence_arr, arr_len); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2489 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2490 if (mcs_data->update_ts && 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2491 (ktime_compare(first_cs_time, max_ktime) != 0)) 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2492 mcs_data->timestamp = ktime_to_ns(first_cs_time); 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2493 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2494 return rc; 215f0c1775d550 drivers/misc/habanalabs/common/command_submission.c Ohad Sharabi 2021-06-14 2495 } --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org