[kbuild-all] drivers/net/ethernet/google/gve/gve_tx.c:507:25: warning: variable 'buf' set but not used

Hi Catherine, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 1d94330a437a573cfdf848f6743b1ed169242c8a commit: 6f007c6486d69967ac1d9e67df9ae9c77d49f1cc gve: Add support for raw addressing in the tx path date: 6 weeks ago config: i386-randconfig-r026-20210117 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 6f007c6486d69967ac1d9e67df9ae9c77d49f1cc # save the attached .config to linux build tree make W=1 ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): drivers/net/ethernet/google/gve/gve_tx.c: In function 'gve_tx_add_skb_no_copy': 507 | struct gve_tx_dma_buf *buf; | ^~~ vim +/buf +507 drivers/net/ethernet/google/gve/gve_tx.c 497 498 static int gve_tx_add_skb_no_copy(struct gve_priv *priv, struct gve_tx_ring *tx, 499 struct sk_buff *skb) 500 { 501 const struct skb_shared_info *shinfo = skb_shinfo(skb); 502 int hlen, payload_nfrags, l4_hdr_offset; 503 union gve_tx_desc *pkt_desc, *seg_desc; 504 struct gve_tx_buffer_state *info; 505 bool is_gso = skb_is_gso(skb); 506 u32 idx = tx->req & tx->mask; 508 u64 addr; 509 u32 len; 510 int i; 511 512 info = &tx->info[idx]; 513 pkt_desc = &tx->desc[idx]; 514 515 l4_hdr_offset = skb_checksum_start_offset(skb); 516 /* If the skb is gso, then we want only up to the tcp header in the first segment 517 * to efficiently replicate on each segment otherwise we want the linear portion 518 * of the skb (which will contain the checksum because skb->csum_start and 519 * skb->csum_offset are given relative to skb->head) in the first segment. 520 */ 521 hlen = is_gso ? l4_hdr_offset + tcp_hdrlen(skb) : skb_headlen(skb); 522 len = skb_headlen(skb); 523 524 info->skb = skb; 525 526 addr = dma_map_single(tx->dev, skb->data, len, DMA_TO_DEVICE); 527 if (unlikely(dma_mapping_error(tx->dev, addr))) { 528 tx->dma_mapping_error++; 529 goto drop; 530 } 531 buf = &info->buf; 532 dma_unmap_len_set(buf, len, len); 533 dma_unmap_addr_set(buf, dma, addr); 534 535 payload_nfrags = shinfo->nr_frags; 536 if (hlen < len) { 537 /* For gso the rest of the linear portion of the skb needs to 538 * be in its own descriptor. 539 */ 540 payload_nfrags++; 541 gve_tx_fill_pkt_desc(pkt_desc, skb, is_gso, l4_hdr_offset, 542 1 + payload_nfrags, hlen, addr); 543 544 len -= hlen; 545 addr += hlen; 546 idx = (tx->req + 1) & tx->mask; 547 seg_desc = &tx->desc[idx]; 548 gve_tx_fill_seg_desc(seg_desc, skb, is_gso, len, addr); 549 } else { 550 gve_tx_fill_pkt_desc(pkt_desc, skb, is_gso, l4_hdr_offset, 551 1 + payload_nfrags, hlen, addr); 552 } 553 554 for (i = 0; i < shinfo->nr_frags; i++) { 555 const skb_frag_t *frag = &shinfo->frags[i]; 556 557 idx = (idx + 1) & tx->mask; 558 seg_desc = &tx->desc[idx]; 559 len = skb_frag_size(frag); 560 addr = skb_frag_dma_map(tx->dev, frag, 0, len, DMA_TO_DEVICE); 561 if (unlikely(dma_mapping_error(tx->dev, addr))) { 562 tx->dma_mapping_error++; 563 goto unmap_drop; 564 } 565 buf = &tx->info[idx].buf; 566 tx->info[idx].skb = NULL; 567 dma_unmap_len_set(buf, len, len); 568 dma_unmap_addr_set(buf, dma, addr); 569 570 gve_tx_fill_seg_desc(seg_desc, skb, is_gso, len, addr); 571 } 572 573 return 1 + payload_nfrags; 574 575 unmap_drop: 576 i += (payload_nfrags == shinfo->nr_frags ? 1 : 2); 577 while (i--) { 578 idx--; 579 gve_tx_unmap_buf(tx->dev, &tx->info[idx & tx->mask]); 580 } 581 drop: 582 tx->dropped_pkt++; 583 return 0; 584 } 585 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org