Hi Jason, kernel test robot noticed the following build warnings: [auto build test WARNING on net/main] url: https://github.com/intel-lab-lkp/linux/commits/Jason-Xing/stmmac-xsk-fix-underflow-of-budget-in-zerocopy-mode/20250722-215348 base: net/main patch link: https://lore.kernel.org/r/20250722135057.85386-2-kerneljasonxing%40gmail.com patch subject: [Intel-wired-lan] [PATCH net v2 1/2] stmmac: xsk: fix underflow of budget in zerocopy mode config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20250723/202507231458.meHSJi2g-lkp@xxxxxxxxx/config) compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250723/202507231458.meHSJi2g-lkp@xxxxxxxxx/reproduce) 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> | Closes: https://lore.kernel.org/oe-kbuild-all/202507231458.meHSJi2g-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2601:3: warning: misleading indentation; statement is not part of the previous 'for' [-Wmisleading-indentation] 2601 | struct xsk_tx_metadata *meta = NULL; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2599:2: note: previous statement is here 2599 | for (; budget > 0; budget--) | ^ >> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2600:34: warning: unused variable 'meta_req' [-Wunused-variable] 2600 | struct stmmac_metadata_request meta_req; | ^~~~~~~~ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2611:4: error: 'break' statement not in loop or switch statement 2611 | break; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2615:4: error: 'break' statement not in loop or switch statement 2615 | break; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2621:4: error: 'continue' statement not in loop statement 2621 | continue; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2660:3: error: use of undeclared identifier 'meta_req' 2660 | meta_req.priv = priv; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2661:3: error: use of undeclared identifier 'meta_req' 2661 | meta_req.tx_desc = tx_desc; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2662:3: error: use of undeclared identifier 'meta_req' 2662 | meta_req.set_ic = &set_ic; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2663:3: error: use of undeclared identifier 'meta_req' 2663 | meta_req.tbs = tx_q->tbs; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2664:3: error: use of undeclared identifier 'meta_req' 2664 | meta_req.edesc = &tx_q->dma_entx[entry]; | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2666:7: error: use of undeclared identifier 'meta_req'; did you mean 'net_eq'? 2666 | &meta_req); | ^~~~~~~~ | net_eq include/net/net_namespace.h:292:5: note: 'net_eq' declared here 292 | int net_eq(const struct net *net1, const struct net *net2) | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2685:25: error: expected parameter declarator 2685 | u64_stats_update_begin(&txq_stats->napi_syncp); | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2685:25: error: expected ')' drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2685:24: note: to match this '(' 2685 | u64_stats_update_begin(&txq_stats->napi_syncp); | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2685:2: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int] 2685 | u64_stats_update_begin(&txq_stats->napi_syncp); | ^ | int drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2685:24: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes] 2685 | u64_stats_update_begin(&txq_stats->napi_syncp); | ^ | void drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2685:2: error: a function declaration without a prototype is deprecated in all versions of C and is treated as a zero-parameter prototype in C23, conflicting with a previous declaration [-Werror,-Wdeprecated-non-prototype] 2685 | u64_stats_update_begin(&txq_stats->napi_syncp); | ^ include/linux/u64_stats_sync.h:181:20: note: conflicting prototype is here 181 | static inline void u64_stats_update_begin(struct u64_stats_sync *syncp) | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2685:2: error: conflicting types for 'u64_stats_update_begin' 2685 | u64_stats_update_begin(&txq_stats->napi_syncp); | ^ include/linux/u64_stats_sync.h:181:20: note: previous definition is here 181 | static inline void u64_stats_update_begin(struct u64_stats_sync *syncp) | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2686:16: error: expected parameter declarator 2686 | u64_stats_add(&txq_stats->napi.tx_set_ic_bit, tx_set_ic_bit); | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2686:16: error: expected ')' drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2686:15: note: to match this '(' 2686 | u64_stats_add(&txq_stats->napi.tx_set_ic_bit, tx_set_ic_bit); | ^ drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2686:2: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int] 2686 | u64_stats_add(&txq_stats->napi.tx_set_ic_bit, tx_set_ic_bit); | ^ | int drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2686:15: error: a function declaration without a prototype is deprecated in all versions of C [-Werror,-Wstrict-prototypes] 2686 | u64_stats_add(&txq_stats->napi.tx_set_ic_bit, tx_set_ic_bit); | ^ | void fatal error: too many errors emitted, stopping now [-ferror-limit=] 2 warnings and 20 errors generated. vim +/for +2601 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c 1347b419318d6af Song Yoong Siang 2023-11-27 2581 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2582 static bool stmmac_xdp_xmit_zc(struct stmmac_priv *priv, u32 queue, u32 budget) 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2583 { 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2584 struct netdev_queue *nq = netdev_get_tx_queue(priv->dev, queue); 8531c80800c10e8 Christian Marangi 2022-07-23 2585 struct stmmac_tx_queue *tx_q = &priv->dma_conf.tx_queue[queue]; 8070274b472e2e9 Jisheng Zhang 2023-09-18 2586 struct stmmac_txq_stats *txq_stats = &priv->xstats.txq_stats[queue]; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2587 struct xsk_buff_pool *pool = tx_q->xsk_pool; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2588 unsigned int entry = tx_q->cur_tx; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2589 struct dma_desc *tx_desc = NULL; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2590 struct xdp_desc xdp_desc; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2591 bool work_done = true; 133466c3bbe171f Jisheng Zhang 2023-07-18 2592 u32 tx_set_ic_bit = 0; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2593 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2594 /* Avoids TX time-out as we are sharing with slow path */ e92af33e472cf3a Alexander Lobakin 2021-11-17 2595 txq_trans_cond_update(nq); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2596 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2597 budget = min(budget, stmmac_tx_avail(priv, queue)); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2598 9074ec4e205d86d Jason Xing 2025-07-22 2599 for (; budget > 0; budget--) 1347b419318d6af Song Yoong Siang 2023-11-27 @2600 struct stmmac_metadata_request meta_req; 1347b419318d6af Song Yoong Siang 2023-11-27 @2601 struct xsk_tx_metadata *meta = NULL; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2602 dma_addr_t dma_addr; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2603 bool set_ic; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2604 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2605 /* We are sharing with slow path and stop XSK TX desc submission when 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2606 * available TX ring is less than threshold. 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2607 */ 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2608 if (unlikely(stmmac_tx_avail(priv, queue) < STMMAC_TX_XSK_AVAIL) || 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2609 !netif_carrier_ok(priv->dev)) { 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2610 work_done = false; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2611 break; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2612 } 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2613 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2614 if (!xsk_tx_peek_desc(pool, &xdp_desc)) 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2615 break; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2616 bd17382ac36ed97 Xiaolei Wang 2024-05-13 2617 if (priv->est && priv->est->enable && bd17382ac36ed97 Xiaolei Wang 2024-05-13 2618 priv->est->max_sdu[queue] && bd17382ac36ed97 Xiaolei Wang 2024-05-13 2619 xdp_desc.len > priv->est->max_sdu[queue]) { c5c3e1bfc9e0ee7 Rohan G Thomas 2024-01-27 2620 priv->xstats.max_sdu_txq_drop[queue]++; c5c3e1bfc9e0ee7 Rohan G Thomas 2024-01-27 2621 continue; c5c3e1bfc9e0ee7 Rohan G Thomas 2024-01-27 2622 } c5c3e1bfc9e0ee7 Rohan G Thomas 2024-01-27 2623 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2624 if (likely(priv->extend_desc)) 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2625 tx_desc = (struct dma_desc *)(tx_q->dma_etx + entry); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2626 else if (tx_q->tbs & STMMAC_TBS_AVAIL) 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2627 tx_desc = &tx_q->dma_entx[entry].basic; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2628 else 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2629 tx_desc = tx_q->dma_tx + entry; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2630 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2631 dma_addr = xsk_buff_raw_get_dma(pool, xdp_desc.addr); 1347b419318d6af Song Yoong Siang 2023-11-27 2632 meta = xsk_buff_get_metadata(pool, xdp_desc.addr); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2633 xsk_buff_raw_dma_sync_for_device(pool, dma_addr, xdp_desc.len); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2634 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2635 tx_q->tx_skbuff_dma[entry].buf_type = STMMAC_TXBUF_T_XSK_TX; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2636 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2637 /* To return XDP buffer to XSK pool, we simple call 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2638 * xsk_tx_completed(), so we don't need to fill up 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2639 * 'buf' and 'xdpf'. 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2640 */ 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2641 tx_q->tx_skbuff_dma[entry].buf = 0; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2642 tx_q->xdpf[entry] = NULL; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2643 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2644 tx_q->tx_skbuff_dma[entry].map_as_page = false; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2645 tx_q->tx_skbuff_dma[entry].len = xdp_desc.len; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2646 tx_q->tx_skbuff_dma[entry].last_segment = true; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2647 tx_q->tx_skbuff_dma[entry].is_jumbo = false; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2648 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2649 stmmac_set_desc_addr(priv, tx_desc, dma_addr); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2650 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2651 tx_q->tx_count_frames++; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2652 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2653 if (!priv->tx_coal_frames[queue]) 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2654 set_ic = false; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2655 else if (tx_q->tx_count_frames % priv->tx_coal_frames[queue] == 0) 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2656 set_ic = true; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2657 else 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2658 set_ic = false; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2659 1347b419318d6af Song Yoong Siang 2023-11-27 2660 meta_req.priv = priv; 1347b419318d6af Song Yoong Siang 2023-11-27 2661 meta_req.tx_desc = tx_desc; 1347b419318d6af Song Yoong Siang 2023-11-27 2662 meta_req.set_ic = &set_ic; 04f64dea13640fb Song Yoong Siang 2025-02-16 2663 meta_req.tbs = tx_q->tbs; 04f64dea13640fb Song Yoong Siang 2025-02-16 2664 meta_req.edesc = &tx_q->dma_entx[entry]; 1347b419318d6af Song Yoong Siang 2023-11-27 2665 xsk_tx_metadata_request(meta, &stmmac_xsk_tx_metadata_ops, 1347b419318d6af Song Yoong Siang 2023-11-27 2666 &meta_req); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2667 if (set_ic) { 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2668 tx_q->tx_count_frames = 0; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2669 stmmac_set_tx_ic(priv, tx_desc); 133466c3bbe171f Jisheng Zhang 2023-07-18 2670 tx_set_ic_bit++; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2671 } 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2672 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2673 stmmac_prepare_tx_desc(priv, tx_desc, 1, xdp_desc.len, 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2674 true, priv->mode, true, true, 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2675 xdp_desc.len); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2676 ad72f783de06827 Yanteng Si 2024-08-07 2677 stmmac_enable_dma_transmission(priv, priv->ioaddr, queue); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2678 1347b419318d6af Song Yoong Siang 2023-11-27 2679 xsk_tx_metadata_to_compl(meta, 1347b419318d6af Song Yoong Siang 2023-11-27 2680 &tx_q->tx_skbuff_dma[entry].xsk_meta); 1347b419318d6af Song Yoong Siang 2023-11-27 2681 8531c80800c10e8 Christian Marangi 2022-07-23 2682 tx_q->cur_tx = STMMAC_GET_ENTRY(tx_q->cur_tx, priv->dma_conf.dma_tx_size); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2683 entry = tx_q->cur_tx; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2684 } 38cc3c6dcc09dc3 Petr Tesarik 2024-02-03 2685 u64_stats_update_begin(&txq_stats->napi_syncp); 38cc3c6dcc09dc3 Petr Tesarik 2024-02-03 2686 u64_stats_add(&txq_stats->napi.tx_set_ic_bit, tx_set_ic_bit); 38cc3c6dcc09dc3 Petr Tesarik 2024-02-03 2687 u64_stats_update_end(&txq_stats->napi_syncp); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2688 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2689 if (tx_desc) { 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2690 stmmac_flush_tx_descriptors(priv, queue); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2691 xsk_tx_release(pool); 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2692 } 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2693 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2694 /* Return true if all of the 3 conditions are met 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2695 * a) TX Budget is still available 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2696 * b) work_done = true when XSK TX desc peek is empty (no more 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2697 * pending XSK TX for transmission) 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2698 */ 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2699 return !!budget && work_done; 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2700 } 132c32ee5bc09b1 Ong Boon Leong 2021-04-13 2701 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
