Hi Nicolin, kernel test robot noticed the following build warnings:
[auto build test WARNING on 92a09c47464d040866cf2b4cd052bc60555185fb] url: https://github.com/intel-lab-lkp/linux/commits/Nicolin-Chen/iommufd-viommu-Add-driver-allocated-vDEVICE-support/20250509-110521 base: 92a09c47464d040866cf2b4cd052bc60555185fb patch link: https://lore.kernel.org/r/ee9ee287264fd75eb4fc64a63f20d03e9ba18161.1746757630.git.nicolinc%40nvidia.com patch subject: [PATCH v4 14/23] iommufd: Add mmap interface config: i386-buildonly-randconfig-003-20250509 (https://download.01.org/0day-ci/archive/20250509/202505092119.ualkhnix-...@intel.com/config) compiler: clang version 20.1.2 (https://github.com/llvm/llvm-project 58df0ef89dd64126512e4ee27b4ac3fd8ddf6247) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250509/202505092119.ualkhnix-...@intel.com/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 <l...@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202505092119.ualkhnix-...@intel.com/ All warnings (new ones prefixed by >>): >> drivers/iommu/iommufd/driver.c:91:6: warning: variable 'num_pfns' set but >> not used [-Wunused-but-set-variable] 91 | int num_pfns, rc; | ^ 1 warning generated. vim +/num_pfns +91 drivers/iommu/iommufd/driver.c 80 81 /* 82 * Allocate an @offset to return to user space to use for an mmap() syscall 83 * 84 * Driver should use a per-structure helper in include/linux/iommufd.h 85 */ 86 int _iommufd_alloc_mmap(struct iommufd_ctx *ictx, struct iommufd_object *owner, 87 phys_addr_t base, size_t length, unsigned long *offset) 88 { 89 struct iommufd_mmap *immap; 90 unsigned long startp; > 91 int num_pfns, rc; 92 93 if (WARN_ON_ONCE(!offset)) 94 return -EINVAL; 95 if (!PAGE_ALIGNED(base)) 96 return -EINVAL; 97 if (!length || !PAGE_ALIGNED(length)) 98 return -EINVAL; 99 num_pfns = length >> PAGE_SHIFT; 100 101 immap = kzalloc(sizeof(*immap), GFP_KERNEL); 102 if (!immap) 103 return -ENOMEM; 104 immap->owner = owner; 105 immap->base_pfn = base >> PAGE_SHIFT; 106 immap->num_pfns = length >> PAGE_SHIFT; 107 108 rc = mtree_alloc_range(&ictx->mt_mmap, &startp, immap, immap->num_pfns, 109 0, U32_MAX >> PAGE_SHIFT, GFP_KERNEL); 110 if (rc < 0) { 111 kfree(immap); 112 return rc; 113 } 114 115 /* mmap() syscall will right-shift the offset in vma->vm_pgoff */ 116 *offset = startp << PAGE_SHIFT; 117 return 0; 118 } 119 EXPORT_SYMBOL_NS_GPL(_iommufd_alloc_mmap, "IOMMUFD"); 120 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
