* [linux-next:master 6322/7246] drivers/dma/loongson/loongson2-apb-cmc-dma.c:516 loongson2_cmc_dma_tx_status() error: we previously assumed 'lchan->desc' could be null (see line 512)
@ 2026-03-19 9:23 ` Dan Carpenter
0 siblings, 0 replies; 2+ messages in thread
From: kernel test robot @ 2026-03-19 4:01 UTC (permalink / raw)
To: oe-kbuild; +Cc: lkp, Dan Carpenter
BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
TO: Binbin Zhou <zhoubinbin@loongson.cn>
CC: Vinod Koul <vkoul@kernel.org>
CC: Frank Li <Frank.Li@nxp.com>
CC: Huacai Chen <chenhuacai@loongson.cn>
tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head: 8e42d2514a7e8eb8d740d0ba82339dd6c0b6463f
commit: 1c0028e725f156ebabe68b0025f9c8e7a6170ffd [6322/7246] dmaengine: loongson: New driver for the Loongson Multi-Channel DMA controller
:::::: branch date: 11 hours ago
:::::: commit date: 2 days ago
config: m68k-randconfig-r073-20260318 (https://download.01.org/0day-ci/archive/20260319/202603191117.QkPVup2Y-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 13.4.0
smatch: v0.5.0-9004-gb810ac53
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@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202603191117.QkPVup2Y-lkp@intel.com/
smatch warnings:
drivers/dma/loongson/loongson2-apb-cmc-dma.c:516 loongson2_cmc_dma_tx_status() error: we previously assumed 'lchan->desc' could be null (see line 512)
drivers/dma/loongson/loongson2-apb-cmc-dma.c:677 loongson2_cmc_dma_probe() warn: unsigned 'lchan->irq' is never less than zero.
vim +516 drivers/dma/loongson/loongson2-apb-cmc-dma.c
1c0028e725f156 Binbin Zhou 2026-03-07 498
1c0028e725f156 Binbin Zhou 2026-03-07 499 static enum dma_status loongson2_cmc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1c0028e725f156 Binbin Zhou 2026-03-07 500 struct dma_tx_state *state)
1c0028e725f156 Binbin Zhou 2026-03-07 501 {
1c0028e725f156 Binbin Zhou 2026-03-07 502 struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan);
1c0028e725f156 Binbin Zhou 2026-03-07 503 struct virt_dma_desc *vdesc;
1c0028e725f156 Binbin Zhou 2026-03-07 504 enum dma_status status;
1c0028e725f156 Binbin Zhou 2026-03-07 505
1c0028e725f156 Binbin Zhou 2026-03-07 506 status = dma_cookie_status(chan, cookie, state);
1c0028e725f156 Binbin Zhou 2026-03-07 507 if (status == DMA_COMPLETE || !state)
1c0028e725f156 Binbin Zhou 2026-03-07 508 return status;
1c0028e725f156 Binbin Zhou 2026-03-07 509
1c0028e725f156 Binbin Zhou 2026-03-07 510 scoped_guard(spinlock_irqsave, &lchan->vchan.lock) {
1c0028e725f156 Binbin Zhou 2026-03-07 511 vdesc = vchan_find_desc(&lchan->vchan, cookie);
1c0028e725f156 Binbin Zhou 2026-03-07 @512 if (lchan->desc && cookie == lchan->desc->vdesc.tx.cookie)
1c0028e725f156 Binbin Zhou 2026-03-07 513 state->residue = loongson2_cmc_dma_desc_residue(lchan, lchan->desc,
1c0028e725f156 Binbin Zhou 2026-03-07 514 lchan->next_sg);
1c0028e725f156 Binbin Zhou 2026-03-07 515 else if (vdesc)
1c0028e725f156 Binbin Zhou 2026-03-07 @516 state->residue = loongson2_cmc_dma_desc_residue(lchan,
1c0028e725f156 Binbin Zhou 2026-03-07 517 to_lmdma_desc(vdesc), 0);
1c0028e725f156 Binbin Zhou 2026-03-07 518 }
1c0028e725f156 Binbin Zhou 2026-03-07 519
1c0028e725f156 Binbin Zhou 2026-03-07 520 return status;
1c0028e725f156 Binbin Zhou 2026-03-07 521 }
1c0028e725f156 Binbin Zhou 2026-03-07 522
1c0028e725f156 Binbin Zhou 2026-03-07 523 static void loongson2_cmc_dma_free_chan_resources(struct dma_chan *chan)
1c0028e725f156 Binbin Zhou 2026-03-07 524 {
1c0028e725f156 Binbin Zhou 2026-03-07 525 vchan_free_chan_resources(to_virt_chan(chan));
1c0028e725f156 Binbin Zhou 2026-03-07 526 }
1c0028e725f156 Binbin Zhou 2026-03-07 527
1c0028e725f156 Binbin Zhou 2026-03-07 528 static void loongson2_cmc_dma_desc_free(struct virt_dma_desc *vdesc)
1c0028e725f156 Binbin Zhou 2026-03-07 529 {
1c0028e725f156 Binbin Zhou 2026-03-07 530 kfree(to_lmdma_desc(vdesc));
1c0028e725f156 Binbin Zhou 2026-03-07 531 }
1c0028e725f156 Binbin Zhou 2026-03-07 532
1c0028e725f156 Binbin Zhou 2026-03-07 533 static bool loongson2_cmc_dma_acpi_filter(struct dma_chan *chan, void *param)
1c0028e725f156 Binbin Zhou 2026-03-07 534 {
1c0028e725f156 Binbin Zhou 2026-03-07 535 struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan);
1c0028e725f156 Binbin Zhou 2026-03-07 536 struct acpi_dma_spec *dma_spec = param;
1c0028e725f156 Binbin Zhou 2026-03-07 537
1c0028e725f156 Binbin Zhou 2026-03-07 538 memset(&lchan->chan_reg, 0, sizeof(struct loongson2_cmc_dma_chan_reg));
1c0028e725f156 Binbin Zhou 2026-03-07 539 lchan->chan_reg.ccr = dma_spec->chan_id & LOONGSON2_CMCDMA_STREAM_MASK;
1c0028e725f156 Binbin Zhou 2026-03-07 540
1c0028e725f156 Binbin Zhou 2026-03-07 541 return true;
1c0028e725f156 Binbin Zhou 2026-03-07 542 }
1c0028e725f156 Binbin Zhou 2026-03-07 543
1c0028e725f156 Binbin Zhou 2026-03-07 544 static int loongson2_cmc_dma_acpi_controller_register(struct loongson2_cmc_dma_dev *lddev)
1c0028e725f156 Binbin Zhou 2026-03-07 545 {
1c0028e725f156 Binbin Zhou 2026-03-07 546 struct device *dev = lddev->ddev.dev;
1c0028e725f156 Binbin Zhou 2026-03-07 547 struct acpi_dma_filter_info *info;
1c0028e725f156 Binbin Zhou 2026-03-07 548
1c0028e725f156 Binbin Zhou 2026-03-07 549 if (!is_acpi_node(dev_fwnode(dev)))
1c0028e725f156 Binbin Zhou 2026-03-07 550 return 0;
1c0028e725f156 Binbin Zhou 2026-03-07 551
1c0028e725f156 Binbin Zhou 2026-03-07 552 info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
1c0028e725f156 Binbin Zhou 2026-03-07 553 if (!info)
1c0028e725f156 Binbin Zhou 2026-03-07 554 return -ENOMEM;
1c0028e725f156 Binbin Zhou 2026-03-07 555
1c0028e725f156 Binbin Zhou 2026-03-07 556 dma_cap_zero(info->dma_cap);
1c0028e725f156 Binbin Zhou 2026-03-07 557 info->dma_cap = lddev->ddev.cap_mask;
1c0028e725f156 Binbin Zhou 2026-03-07 558 info->filter_fn = loongson2_cmc_dma_acpi_filter;
1c0028e725f156 Binbin Zhou 2026-03-07 559
1c0028e725f156 Binbin Zhou 2026-03-07 560 return devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info);
1c0028e725f156 Binbin Zhou 2026-03-07 561 }
1c0028e725f156 Binbin Zhou 2026-03-07 562
1c0028e725f156 Binbin Zhou 2026-03-07 563 static struct dma_chan *loongson2_cmc_dma_of_xlate(struct of_phandle_args *dma_spec,
1c0028e725f156 Binbin Zhou 2026-03-07 564 struct of_dma *ofdma)
1c0028e725f156 Binbin Zhou 2026-03-07 565 {
1c0028e725f156 Binbin Zhou 2026-03-07 566 struct loongson2_cmc_dma_dev *lddev = ofdma->of_dma_data;
1c0028e725f156 Binbin Zhou 2026-03-07 567 struct device *dev = lddev->ddev.dev;
1c0028e725f156 Binbin Zhou 2026-03-07 568 struct loongson2_cmc_dma_chan *lchan;
1c0028e725f156 Binbin Zhou 2026-03-07 569 struct dma_chan *chan;
1c0028e725f156 Binbin Zhou 2026-03-07 570
1c0028e725f156 Binbin Zhou 2026-03-07 571 if (dma_spec->args_count < 2)
1c0028e725f156 Binbin Zhou 2026-03-07 572 return ERR_PTR(-EINVAL);
1c0028e725f156 Binbin Zhou 2026-03-07 573
1c0028e725f156 Binbin Zhou 2026-03-07 574 if (dma_spec->args[0] >= lddev->nr_channels) {
1c0028e725f156 Binbin Zhou 2026-03-07 575 dev_err(dev, "Invalid channel id.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 576 return ERR_PTR(-EINVAL);
1c0028e725f156 Binbin Zhou 2026-03-07 577 }
1c0028e725f156 Binbin Zhou 2026-03-07 578
1c0028e725f156 Binbin Zhou 2026-03-07 579 lchan = &lddev->chan[dma_spec->args[0]];
1c0028e725f156 Binbin Zhou 2026-03-07 580 chan = dma_get_slave_channel(&lchan->vchan.chan);
1c0028e725f156 Binbin Zhou 2026-03-07 581 if (!chan) {
1c0028e725f156 Binbin Zhou 2026-03-07 582 dev_err(dev, "No more channels available.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 583 return ERR_PTR(-EINVAL);
1c0028e725f156 Binbin Zhou 2026-03-07 584 }
1c0028e725f156 Binbin Zhou 2026-03-07 585
1c0028e725f156 Binbin Zhou 2026-03-07 586 memset(&lchan->chan_reg, 0, sizeof(struct loongson2_cmc_dma_chan_reg));
1c0028e725f156 Binbin Zhou 2026-03-07 587 lchan->chan_reg.ccr = dma_spec->args[1] & LOONGSON2_CMCDMA_STREAM_MASK;
1c0028e725f156 Binbin Zhou 2026-03-07 588
1c0028e725f156 Binbin Zhou 2026-03-07 589 return chan;
1c0028e725f156 Binbin Zhou 2026-03-07 590 }
1c0028e725f156 Binbin Zhou 2026-03-07 591
1c0028e725f156 Binbin Zhou 2026-03-07 592 static int loongson2_cmc_dma_of_controller_register(struct loongson2_cmc_dma_dev *lddev)
1c0028e725f156 Binbin Zhou 2026-03-07 593 {
1c0028e725f156 Binbin Zhou 2026-03-07 594 struct device *dev = lddev->ddev.dev;
1c0028e725f156 Binbin Zhou 2026-03-07 595
1c0028e725f156 Binbin Zhou 2026-03-07 596 if (!is_of_node(dev_fwnode(dev)))
1c0028e725f156 Binbin Zhou 2026-03-07 597 return 0;
1c0028e725f156 Binbin Zhou 2026-03-07 598
1c0028e725f156 Binbin Zhou 2026-03-07 599 return of_dma_controller_register(dev->of_node, loongson2_cmc_dma_of_xlate, lddev);
1c0028e725f156 Binbin Zhou 2026-03-07 600 }
1c0028e725f156 Binbin Zhou 2026-03-07 601
1c0028e725f156 Binbin Zhou 2026-03-07 602 static int loongson2_cmc_dma_probe(struct platform_device *pdev)
1c0028e725f156 Binbin Zhou 2026-03-07 603 {
1c0028e725f156 Binbin Zhou 2026-03-07 604 const struct loongson2_cmc_dma_config *config;
1c0028e725f156 Binbin Zhou 2026-03-07 605 struct loongson2_cmc_dma_chan *lchan;
1c0028e725f156 Binbin Zhou 2026-03-07 606 struct loongson2_cmc_dma_dev *lddev;
1c0028e725f156 Binbin Zhou 2026-03-07 607 struct device *dev = &pdev->dev;
1c0028e725f156 Binbin Zhou 2026-03-07 608 struct dma_device *ddev;
1c0028e725f156 Binbin Zhou 2026-03-07 609 u32 nr_chans, i;
1c0028e725f156 Binbin Zhou 2026-03-07 610 int ret;
1c0028e725f156 Binbin Zhou 2026-03-07 611
1c0028e725f156 Binbin Zhou 2026-03-07 612 config = (const struct loongson2_cmc_dma_config *)device_get_match_data(dev);
1c0028e725f156 Binbin Zhou 2026-03-07 613 if (!config)
1c0028e725f156 Binbin Zhou 2026-03-07 614 return -EINVAL;
1c0028e725f156 Binbin Zhou 2026-03-07 615
1c0028e725f156 Binbin Zhou 2026-03-07 616 ret = device_property_read_u32(dev, "dma-channels", &nr_chans);
1c0028e725f156 Binbin Zhou 2026-03-07 617 if (ret || nr_chans > config->max_channels) {
1c0028e725f156 Binbin Zhou 2026-03-07 618 dev_err(dev, "missing or invalid dma-channels property\n");
1c0028e725f156 Binbin Zhou 2026-03-07 619 nr_chans = config->max_channels;
1c0028e725f156 Binbin Zhou 2026-03-07 620 }
1c0028e725f156 Binbin Zhou 2026-03-07 621
1c0028e725f156 Binbin Zhou 2026-03-07 622 lddev = devm_kzalloc(dev, struct_size(lddev, chan, nr_chans), GFP_KERNEL);
1c0028e725f156 Binbin Zhou 2026-03-07 623 if (!lddev)
1c0028e725f156 Binbin Zhou 2026-03-07 624 return -ENOMEM;
1c0028e725f156 Binbin Zhou 2026-03-07 625
1c0028e725f156 Binbin Zhou 2026-03-07 626 lddev->base = devm_platform_ioremap_resource(pdev, 0);
1c0028e725f156 Binbin Zhou 2026-03-07 627 if (IS_ERR(lddev->base))
1c0028e725f156 Binbin Zhou 2026-03-07 628 return PTR_ERR(lddev->base);
1c0028e725f156 Binbin Zhou 2026-03-07 629
1c0028e725f156 Binbin Zhou 2026-03-07 630 platform_set_drvdata(pdev, lddev);
1c0028e725f156 Binbin Zhou 2026-03-07 631 lddev->nr_channels = nr_chans;
1c0028e725f156 Binbin Zhou 2026-03-07 632 lddev->chan_reg_offset = config->chan_reg_offset;
1c0028e725f156 Binbin Zhou 2026-03-07 633
1c0028e725f156 Binbin Zhou 2026-03-07 634 lddev->dma_clk = devm_clk_get_optional_enabled(dev, NULL);
1c0028e725f156 Binbin Zhou 2026-03-07 635 if (IS_ERR(lddev->dma_clk))
1c0028e725f156 Binbin Zhou 2026-03-07 636 return dev_err_probe(dev, PTR_ERR(lddev->dma_clk), "Failed to get dma clock\n");
1c0028e725f156 Binbin Zhou 2026-03-07 637
1c0028e725f156 Binbin Zhou 2026-03-07 638 ddev = &lddev->ddev;
1c0028e725f156 Binbin Zhou 2026-03-07 639 ddev->dev = dev;
1c0028e725f156 Binbin Zhou 2026-03-07 640
1c0028e725f156 Binbin Zhou 2026-03-07 641 dma_cap_zero(ddev->cap_mask);
1c0028e725f156 Binbin Zhou 2026-03-07 642 dma_cap_set(DMA_SLAVE, ddev->cap_mask);
1c0028e725f156 Binbin Zhou 2026-03-07 643 dma_cap_set(DMA_PRIVATE, ddev->cap_mask);
1c0028e725f156 Binbin Zhou 2026-03-07 644 dma_cap_set(DMA_CYCLIC, ddev->cap_mask);
1c0028e725f156 Binbin Zhou 2026-03-07 645
1c0028e725f156 Binbin Zhou 2026-03-07 646 ddev->device_free_chan_resources = loongson2_cmc_dma_free_chan_resources;
1c0028e725f156 Binbin Zhou 2026-03-07 647 ddev->device_config = loongson2_cmc_dma_slave_config;
1c0028e725f156 Binbin Zhou 2026-03-07 648 ddev->device_prep_slave_sg = loongson2_cmc_dma_prep_slave_sg;
1c0028e725f156 Binbin Zhou 2026-03-07 649 ddev->device_prep_dma_cyclic = loongson2_cmc_dma_prep_dma_cyclic;
1c0028e725f156 Binbin Zhou 2026-03-07 650 ddev->device_issue_pending = loongson2_cmc_dma_issue_pending;
1c0028e725f156 Binbin Zhou 2026-03-07 651 ddev->device_synchronize = loongson2_cmc_dma_synchronize;
1c0028e725f156 Binbin Zhou 2026-03-07 652 ddev->device_tx_status = loongson2_cmc_dma_tx_status;
1c0028e725f156 Binbin Zhou 2026-03-07 653 ddev->device_terminate_all = loongson2_cmc_dma_terminate_all;
1c0028e725f156 Binbin Zhou 2026-03-07 654
1c0028e725f156 Binbin Zhou 2026-03-07 655 ddev->max_sg_burst = LOONSON2_CMCDMA_MAX_DATA_ITEMS;
1c0028e725f156 Binbin Zhou 2026-03-07 656 ddev->src_addr_widths = LOONGSON2_CMCDMA_BUSWIDTHS;
1c0028e725f156 Binbin Zhou 2026-03-07 657 ddev->dst_addr_widths = LOONGSON2_CMCDMA_BUSWIDTHS;
1c0028e725f156 Binbin Zhou 2026-03-07 658 ddev->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1c0028e725f156 Binbin Zhou 2026-03-07 659 INIT_LIST_HEAD(&ddev->channels);
1c0028e725f156 Binbin Zhou 2026-03-07 660
1c0028e725f156 Binbin Zhou 2026-03-07 661 for (i = 0; i < nr_chans; i++) {
1c0028e725f156 Binbin Zhou 2026-03-07 662 lchan = &lddev->chan[i];
1c0028e725f156 Binbin Zhou 2026-03-07 663
1c0028e725f156 Binbin Zhou 2026-03-07 664 lchan->id = i;
1c0028e725f156 Binbin Zhou 2026-03-07 665 lchan->vchan.desc_free = loongson2_cmc_dma_desc_free;
1c0028e725f156 Binbin Zhou 2026-03-07 666 vchan_init(&lchan->vchan, ddev);
1c0028e725f156 Binbin Zhou 2026-03-07 667 }
1c0028e725f156 Binbin Zhou 2026-03-07 668
1c0028e725f156 Binbin Zhou 2026-03-07 669 ret = dmaenginem_async_device_register(ddev);
1c0028e725f156 Binbin Zhou 2026-03-07 670 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 671 return dev_err_probe(dev, ret, "Failed to register DMA engine device.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 672
1c0028e725f156 Binbin Zhou 2026-03-07 673 for (i = 0; i < nr_chans; i++) {
1c0028e725f156 Binbin Zhou 2026-03-07 674 lchan = &lddev->chan[i];
1c0028e725f156 Binbin Zhou 2026-03-07 675
1c0028e725f156 Binbin Zhou 2026-03-07 676 lchan->irq = platform_get_irq(pdev, i);
1c0028e725f156 Binbin Zhou 2026-03-07 @677 if (lchan->irq < 0)
1c0028e725f156 Binbin Zhou 2026-03-07 678 return lchan->irq;
1c0028e725f156 Binbin Zhou 2026-03-07 679
1c0028e725f156 Binbin Zhou 2026-03-07 680 ret = devm_request_irq(dev, lchan->irq, loongson2_cmc_dma_chan_irq, IRQF_SHARED,
1c0028e725f156 Binbin Zhou 2026-03-07 681 dev_name(chan2dev(lchan)), lchan);
1c0028e725f156 Binbin Zhou 2026-03-07 682 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 683 return ret;
1c0028e725f156 Binbin Zhou 2026-03-07 684 }
1c0028e725f156 Binbin Zhou 2026-03-07 685
1c0028e725f156 Binbin Zhou 2026-03-07 686 ret = loongson2_cmc_dma_acpi_controller_register(lddev);
1c0028e725f156 Binbin Zhou 2026-03-07 687 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 688 return dev_err_probe(dev, ret, "Failed to register dma controller with ACPI.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 689
1c0028e725f156 Binbin Zhou 2026-03-07 690 ret = loongson2_cmc_dma_of_controller_register(lddev);
1c0028e725f156 Binbin Zhou 2026-03-07 691 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 692 return dev_err_probe(dev, ret, "Failed to register dma controller with FDT.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 693
1c0028e725f156 Binbin Zhou 2026-03-07 694 dev_info(dev, "Loongson-2 Multi-Channel DMA Controller registered successfully.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 695
1c0028e725f156 Binbin Zhou 2026-03-07 696 return 0;
1c0028e725f156 Binbin Zhou 2026-03-07 697 }
1c0028e725f156 Binbin Zhou 2026-03-07 698
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 2+ messages in thread* [linux-next:master 6322/7246] drivers/dma/loongson/loongson2-apb-cmc-dma.c:516 loongson2_cmc_dma_tx_status() error: we previously assumed 'lchan->desc' could be null (see line 512)
@ 2026-03-19 9:23 ` Dan Carpenter
0 siblings, 0 replies; 2+ messages in thread
From: Dan Carpenter @ 2026-03-19 9:23 UTC (permalink / raw)
To: oe-kbuild, Binbin Zhou
Cc: lkp, oe-kbuild-all, Vinod Koul, Frank Li, Huacai Chen
tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head: 8e42d2514a7e8eb8d740d0ba82339dd6c0b6463f
commit: 1c0028e725f156ebabe68b0025f9c8e7a6170ffd [6322/7246] dmaengine: loongson: New driver for the Loongson Multi-Channel DMA controller
config: m68k-randconfig-r073-20260318 (https://download.01.org/0day-ci/archive/20260319/202603191117.QkPVup2Y-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 13.4.0
smatch: v0.5.0-9004-gb810ac53
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@intel.com>
| Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
| Closes: https://lore.kernel.org/r/202603191117.QkPVup2Y-lkp@intel.com/
smatch warnings:
drivers/dma/loongson/loongson2-apb-cmc-dma.c:516 loongson2_cmc_dma_tx_status() error: we previously assumed 'lchan->desc' could be null (see line 512)
drivers/dma/loongson/loongson2-apb-cmc-dma.c:677 loongson2_cmc_dma_probe() warn: unsigned 'lchan->irq' is never less than zero.
vim +516 drivers/dma/loongson/loongson2-apb-cmc-dma.c
1c0028e725f156 Binbin Zhou 2026-03-07 498
1c0028e725f156 Binbin Zhou 2026-03-07 499 static enum dma_status loongson2_cmc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
1c0028e725f156 Binbin Zhou 2026-03-07 500 struct dma_tx_state *state)
1c0028e725f156 Binbin Zhou 2026-03-07 501 {
1c0028e725f156 Binbin Zhou 2026-03-07 502 struct loongson2_cmc_dma_chan *lchan = to_lmdma_chan(chan);
1c0028e725f156 Binbin Zhou 2026-03-07 503 struct virt_dma_desc *vdesc;
1c0028e725f156 Binbin Zhou 2026-03-07 504 enum dma_status status;
1c0028e725f156 Binbin Zhou 2026-03-07 505
1c0028e725f156 Binbin Zhou 2026-03-07 506 status = dma_cookie_status(chan, cookie, state);
1c0028e725f156 Binbin Zhou 2026-03-07 507 if (status == DMA_COMPLETE || !state)
1c0028e725f156 Binbin Zhou 2026-03-07 508 return status;
1c0028e725f156 Binbin Zhou 2026-03-07 509
1c0028e725f156 Binbin Zhou 2026-03-07 510 scoped_guard(spinlock_irqsave, &lchan->vchan.lock) {
1c0028e725f156 Binbin Zhou 2026-03-07 511 vdesc = vchan_find_desc(&lchan->vchan, cookie);
^^^^^^^^^^^^^
If lchan->vchan is NULL we are toasted here.
1c0028e725f156 Binbin Zhou 2026-03-07 @512 if (lchan->desc && cookie == lchan->desc->vdesc.tx.cookie)
^^^^^^^^^^^
So this NULL check is too late.
1c0028e725f156 Binbin Zhou 2026-03-07 513 state->residue = loongson2_cmc_dma_desc_residue(lchan, lchan->desc,
1c0028e725f156 Binbin Zhou 2026-03-07 514 lchan->next_sg);
1c0028e725f156 Binbin Zhou 2026-03-07 515 else if (vdesc)
1c0028e725f156 Binbin Zhou 2026-03-07 @516 state->residue = loongson2_cmc_dma_desc_residue(lchan,
loongson2_cmc_dma_desc_residue() also dereferences
lchan->desc.
1c0028e725f156 Binbin Zhou 2026-03-07 517 to_lmdma_desc(vdesc), 0);
1c0028e725f156 Binbin Zhou 2026-03-07 518 }
1c0028e725f156 Binbin Zhou 2026-03-07 519
1c0028e725f156 Binbin Zhou 2026-03-07 520 return status;
1c0028e725f156 Binbin Zhou 2026-03-07 521 }
[ snip to probe function ]
1c0028e725f156 Binbin Zhou 2026-03-07 669 ret = dmaenginem_async_device_register(ddev);
1c0028e725f156 Binbin Zhou 2026-03-07 670 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 671 return dev_err_probe(dev, ret, "Failed to register DMA engine device.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 672
1c0028e725f156 Binbin Zhou 2026-03-07 673 for (i = 0; i < nr_chans; i++) {
1c0028e725f156 Binbin Zhou 2026-03-07 674 lchan = &lddev->chan[i];
1c0028e725f156 Binbin Zhou 2026-03-07 675
1c0028e725f156 Binbin Zhou 2026-03-07 676 lchan->irq = platform_get_irq(pdev, i);
1c0028e725f156 Binbin Zhou 2026-03-07 @677 if (lchan->irq < 0)
1c0028e725f156 Binbin Zhou 2026-03-07 678 return lchan->irq;
Make lchan->irq an int. Unsigned breaks error checking.
1c0028e725f156 Binbin Zhou 2026-03-07 679
1c0028e725f156 Binbin Zhou 2026-03-07 680 ret = devm_request_irq(dev, lchan->irq, loongson2_cmc_dma_chan_irq, IRQF_SHARED,
1c0028e725f156 Binbin Zhou 2026-03-07 681 dev_name(chan2dev(lchan)), lchan);
1c0028e725f156 Binbin Zhou 2026-03-07 682 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 683 return ret;
1c0028e725f156 Binbin Zhou 2026-03-07 684 }
1c0028e725f156 Binbin Zhou 2026-03-07 685
1c0028e725f156 Binbin Zhou 2026-03-07 686 ret = loongson2_cmc_dma_acpi_controller_register(lddev);
1c0028e725f156 Binbin Zhou 2026-03-07 687 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 688 return dev_err_probe(dev, ret, "Failed to register dma controller with ACPI.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 689
1c0028e725f156 Binbin Zhou 2026-03-07 690 ret = loongson2_cmc_dma_of_controller_register(lddev);
1c0028e725f156 Binbin Zhou 2026-03-07 691 if (ret)
1c0028e725f156 Binbin Zhou 2026-03-07 692 return dev_err_probe(dev, ret, "Failed to register dma controller with FDT.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 693
1c0028e725f156 Binbin Zhou 2026-03-07 694 dev_info(dev, "Loongson-2 Multi-Channel DMA Controller registered successfully.\n");
1c0028e725f156 Binbin Zhou 2026-03-07 695
1c0028e725f156 Binbin Zhou 2026-03-07 696 return 0;
1c0028e725f156 Binbin Zhou 2026-03-07 697 }
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2026-03-19 9:24 UTC | newest]
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2026-03-19 4:01 [linux-next:master 6322/7246] drivers/dma/loongson/loongson2-apb-cmc-dma.c:516 loongson2_cmc_dma_tx_status() error: we previously assumed 'lchan->desc' could be null (see line 512) kernel test robot
2026-03-19 9:23 ` Dan Carpenter
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