Hi Elson, https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Elson-Roy-Serrao/usb-gadget-Properly-configure-the-device-for-remote-wakeup/20230317-074030 base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing patch link: https://lore.kernel.org/r/1679009888-8239-7-git-send-email-quic_eserrao%40quicinc.com patch subject: [PATCH v12 6/6] usb: gadget: f_ecm: Add suspend/resume and remote wakeup support config: riscv-randconfig-m031-20230319 (https://download.01.org/0day-ci/archive/20230321/202303211515.XaO8YKCz-lkp@xxxxxxxxx/config) compiler: riscv32-linux-gcc (GCC) 12.1.0 If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <error27@xxxxxxxxx> | Link: https://lore.kernel.org/r/202303211515.XaO8YKCz-lkp@xxxxxxxxx/ New smatch warnings: drivers/usb/gadget/function/u_ether.c:474 eth_start_xmit() error: we previously assumed 'dev->port_usb' could be null (see line 466) drivers/usb/gadget/function/u_ether.c:539 eth_start_xmit() warn: variable dereferenced before check 'dev->port_usb' (see line 474) Old smatch warnings: drivers/usb/gadget/function/u_ether.c:553 eth_start_xmit() error: we previously assumed 'skb' could be null (see line 491) vim +474 drivers/usb/gadget/function/u_ether.c 25a79c41ce0ce8 drivers/usb/gadget/u_ether.c Stephen Hemminger 2009-08-31 454 static netdev_tx_t eth_start_xmit(struct sk_buff *skb, 25a79c41ce0ce8 drivers/usb/gadget/u_ether.c Stephen Hemminger 2009-08-31 455 struct net_device *net) 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 456 { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 457 struct eth_dev *dev = netdev_priv(net); 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 458 int length = 0; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 459 int retval; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 460 struct usb_request *req = NULL; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 461 unsigned long flags; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 462 struct usb_ep *in; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 463 u16 cdc_filter; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 464 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 465 spin_lock_irqsave(&dev->lock, flags); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 @466 if (dev->port_usb) { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 467 in = dev->port_usb->in_ep; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 468 cdc_filter = dev->port_usb->cdc_filter; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 469 } else { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 470 in = NULL; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 471 cdc_filter = 0; NULL on this path. 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 472 } 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 473 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 @474 if (dev->port_usb->is_suspend) { ^^^^^^^^^^^^^^^ Dead. (Both ->port_usb warnings are caused by this dereference). 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 475 DBG(dev, "Port suspended. Triggering wakeup\n"); 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 476 netif_stop_queue(net); 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 477 spin_unlock_irqrestore(&dev->lock, flags); 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 478 ether_wakeup_host(dev->port_usb); 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 479 return NETDEV_TX_BUSY; 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 480 } 11f254fc796c87 drivers/usb/gadget/function/u_ether.c Elson Roy Serrao 2023-03-16 481 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 482 spin_unlock_irqrestore(&dev->lock, flags); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 483 8ae01239609b29 drivers/usb/gadget/function/u_ether.c Maciej Żenczykowski 2021-07-01 484 if (!in) { 8ae01239609b29 drivers/usb/gadget/function/u_ether.c Maciej Żenczykowski 2021-07-01 485 if (skb) 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 486 dev_kfree_skb_any(skb); 6ed106549d1747 drivers/usb/gadget/u_ether.c Patrick McHardy 2009-06-23 487 return NETDEV_TX_OK; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 488 } 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 489 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 490 /* apply outgoing CDC or RNDIS filters */ 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 491 if (skb && !is_promisc(cdc_filter)) { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 492 u8 *dest = skb->data; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 493 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 494 if (is_multicast_ether_addr(dest)) { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 495 u16 type; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 496 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 497 /* ignores USB_CDC_PACKET_TYPE_MULTICAST and host 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 498 * SET_ETHERNET_MULTICAST_FILTERS requests 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 499 */ 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 500 if (is_broadcast_ether_addr(dest)) 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 501 type = USB_CDC_PACKET_TYPE_BROADCAST; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 502 else 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 503 type = USB_CDC_PACKET_TYPE_ALL_MULTICAST; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 504 if (!(cdc_filter & type)) { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 505 dev_kfree_skb_any(skb); 6ed106549d1747 drivers/usb/gadget/u_ether.c Patrick McHardy 2009-06-23 506 return NETDEV_TX_OK; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 507 } 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 508 } 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 509 /* ignores USB_CDC_PACKET_TYPE_DIRECTED */ 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 510 } 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 511 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 512 spin_lock_irqsave(&dev->req_lock, flags); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 513 /* 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 514 * this freelist can be empty if an interrupt triggered disconnect() 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 515 * and reconfigured the gadget (shutting down this queue) after the 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 516 * network stack decided to xmit but before we got the spinlock. 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 517 */ 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 518 if (list_empty(&dev->tx_reqs)) { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 519 spin_unlock_irqrestore(&dev->req_lock, flags); 5b548140225c6b drivers/usb/gadget/u_ether.c Patrick McHardy 2009-06-12 520 return NETDEV_TX_BUSY; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 521 } 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 522 fea14e68ff5e11 drivers/usb/gadget/function/u_ether.c Felipe Balbi 2017-03-22 523 req = list_first_entry(&dev->tx_reqs, struct usb_request, list); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 524 list_del(&req->list); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 525 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 526 /* temporarily stop TX queue when the freelist empties */ 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 527 if (list_empty(&dev->tx_reqs)) 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 528 netif_stop_queue(net); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 529 spin_unlock_irqrestore(&dev->req_lock, flags); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 530 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 531 /* no buffer copies needed, unless the network stack did it 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 532 * or the hardware can't use skb buffers. 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 533 * or there's not enough space for extra headers we need 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 534 */ 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 535 if (dev->wrap) { 9b39e9ddedeef4 drivers/usb/gadget/u_ether.c Brian Niebuhr 2009-08-14 536 unsigned long flags; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 537 9b39e9ddedeef4 drivers/usb/gadget/u_ether.c Brian Niebuhr 2009-08-14 538 spin_lock_irqsave(&dev->lock, flags); 9b39e9ddedeef4 drivers/usb/gadget/u_ether.c Brian Niebuhr 2009-08-14 @539 if (dev->port_usb) 9b39e9ddedeef4 drivers/usb/gadget/u_ether.c Brian Niebuhr 2009-08-14 540 skb = dev->wrap(dev->port_usb, skb); 3a383cc0b8cc33 drivers/usb/gadget/function/u_ether.c Greg Kroah-Hartman 2016-09-19 541 spin_unlock_irqrestore(&dev->lock, flags); 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 542 if (!skb) { 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 543 /* Multi frame CDC protocols may store the frame for 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 544 * later which is not a dropped frame. 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 545 */ 88c09eacf560c3 drivers/usb/gadget/function/u_ether.c Peter Chen 2016-07-01 546 if (dev->port_usb && 3a383cc0b8cc33 drivers/usb/gadget/function/u_ether.c Greg Kroah-Hartman 2016-09-19 547 dev->port_usb->supports_multi_frame) 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 548 goto multiframe; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 549 goto drop; 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 550 } 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 551 } 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 552 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 553 length = skb->len; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 554 req->buf = skb->data; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 555 req->context = skb; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 556 req->complete = tx_complete; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 557 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 558 /* NCM requires no zlp if transfer is dwNtbInMaxSize */ 79775f44183840 drivers/usb/gadget/function/u_ether.c Harish Jenny K N 2016-09-09 559 if (dev->port_usb && 79775f44183840 drivers/usb/gadget/function/u_ether.c Harish Jenny K N 2016-09-09 560 dev->port_usb->is_fixed && 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 561 length == dev->port_usb->fixed_in_len && 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 562 (length % in->maxpacket) == 0) 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 563 req->zero = 0; 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 564 else 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 565 req->zero = 1; 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 566 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 567 /* use zlp framing on tx for strict CDC-Ether conformance, 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 568 * though any robust network rx path ignores extra padding. 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 569 * and some hardware doesn't like to write zlps. 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 570 */ 5c1168dbc50828 drivers/usb/gadget/u_ether.c Yauheni Kaliuta 2010-12-08 571 if (req->zero && !dev->zlp && (length % in->maxpacket) == 0) 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 572 length++; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 573 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 574 req->length = length; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 575 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 576 retval = usb_ep_queue(in, req, GFP_ATOMIC); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 577 switch (retval) { 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 578 default: 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 579 DBG(dev, "tx queue err %d\n", retval); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 580 break; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 581 case 0: 860e9538a9482b drivers/usb/gadget/function/u_ether.c Florian Westphal 2016-05-03 582 netif_trans_update(net); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 583 atomic_inc(&dev->tx_qlen); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 584 } 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 585 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 586 if (retval) { 9b39e9ddedeef4 drivers/usb/gadget/u_ether.c Brian Niebuhr 2009-08-14 587 dev_kfree_skb_any(skb); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 588 drop: 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 589 dev->net->stats.tx_dropped++; 6d3865f9d41f15 drivers/usb/gadget/u_ether.c Jim Baxter 2014-07-07 590 multiframe: 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 591 spin_lock_irqsave(&dev->req_lock, flags); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 592 if (list_empty(&dev->tx_reqs)) 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 593 netif_start_queue(net); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 594 list_add(&req->list, &dev->tx_reqs); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 595 spin_unlock_irqrestore(&dev->req_lock, flags); 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 596 } 6ed106549d1747 drivers/usb/gadget/u_ether.c Patrick McHardy 2009-06-23 597 return NETDEV_TX_OK; 2b3d942c487808 drivers/usb/gadget/u_ether.c David Brownell 2008-06-19 598 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
