Hi Ben, I love your patch! Perhaps something to improve: [auto build test WARNING on 53989fad1286e652ea3655ae3367ba698da8d2ff] url: https://github.com/0day-ci/linux/commits/Ben-Widawsky/Add-drivers-for-CXL... base: 53989fad1286e652ea3655ae3367ba698da8d2ff config: riscv-buildonly-randconfig-r001-20211119 (attached as .config) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://github.com/0day-ci/linux/commit/3f74c99d751a24a4c12ba76c23b68c283... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Ben-Widawsky/Add-drivers-for-CXL-ports-and-mem-devices/20211120-080513 git checkout 3f74c99d751a24a4c12ba76c23b68c2832f805e1 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=riscv 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/cxl/pci.c:469:7: warning: variable 'size' set but not used [-Wunused-but-set-variable] u64 size; ^ drivers/cxl/pci.c:516:7: warning: variable 'size' set but not used [-Wunused-but-set-variable] u64 size; ^ dev_warn(&cxlmd->dev, "No component registers (%d)\n", rc); ^~~~~ include/linux/dev_printk.h:146:49: note: expanded from macro 'dev_warn' dev_printk_index_wrap(_dev_warn, KERN_WARNING, dev, dev_fmt(fmt), ##__VA_ARGS__) ^~~ include/linux/dev_printk.h:110:11: note: expanded from macro 'dev_printk_index_wrap' _p_func(dev, fmt, ##__VA_ARGS__); \ ^~~ drivers/cxl/pci.c:630:26: note: initialize the variable 'cxlmd' to silence this warning struct cxl_memdev *cxlmd; ^ = NULL 3 warnings generated. vim +/cxlmd +673 drivers/cxl/pci.c 625 626 static int cxl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) 627 { 628 struct cxl_endpoint_dvsec_info *info; 629 struct cxl_register_map map; 630 struct cxl_memdev *cxlmd; 631 struct cxl_dev_state *cxlds; 632 int rc; 633 634 /* 635 * Double check the anonymous union trickery in struct cxl_regs 636 * FIXME switch to struct_group() 637 */ 638 BUILD_BUG_ON(offsetof(struct cxl_regs, memdev) != 639 offsetof(struct cxl_regs, device_regs.memdev)); 640 641 rc = pcim_enable_device(pdev); 642 if (rc) 643 return rc; 644 645 cxlds = cxl_dev_state_create(&pdev->dev); 646 if (IS_ERR(cxlds)) 647 return PTR_ERR(cxlds); 648 649 cxlds->device_dvsec = pci_find_dvsec_capability(pdev, 650 PCI_DVSEC_VENDOR_ID_CXL, 651 CXL_DVSEC_PCIE_DEVICE); 652 if (!cxlds->device_dvsec) 653 dev_warn(&pdev->dev, 654 "Device DVSEC not present. Expect limited functionality.\n"); 655 else 656 cxlds->wait_media_ready = wait_for_media_ready; 657 658 rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_MEMDEV, &map); 659 if (rc) 660 return rc; 661 662 rc = cxl_map_regs(cxlds, &map); 663 if (rc) 664 return rc; 665 666 /* 667 * If the component registers can't be found, the cxl_pci driver may 668 * still be useful for management functions so don't return an error. 669 */ 670 cxlds->component_reg_phys = CXL_RESOURCE_NONE; 671 rc = cxl_setup_regs(pdev, CXL_REGLOC_RBI_COMPONENT, &map); 672 if (rc) 674 else 675 cxlds->component_reg_phys = cxl_reg_block(pdev, &map); 676 677 rc = cxl_pci_setup_mailbox(cxlds); 678 if (rc) 679 return rc; 680 681 rc = cxl_enumerate_cmds(cxlds); 682 if (rc) 683 return rc; 684 685 rc = cxl_dev_state_identify(cxlds); 686 if (rc) 687 return rc; 688 689 rc = cxl_mem_create_range_info(cxlds); 690 if (rc) 691 return rc; 692 693 info = dvsec_ranges(cxlds); 694 if (IS_ERR(info)) 695 dev_err(&pdev->dev, 696 "Failed to get DVSEC range information (%ld)\n", 697 PTR_ERR(info)); 698 else 699 cxlds->info = info; 700 701 cxlmd = devm_cxl_add_memdev(cxlds); 702 if (IS_ERR(cxlmd)) 703 return PTR_ERR(cxlmd); 704 705 if (range_len(&cxlds->pmem_range) && IS_ENABLED(CONFIG_CXL_PMEM)) 706 rc = devm_cxl_add_nvdimm(&pdev->dev, cxlmd); 707 708 return rc; 709 } 710 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org