[kbuild-all] [luxis1999-iommufd:iommufd-v5.16-rc3 23/25] drivers/iommu/iommufd/io_pagetable.c:1535:6: warning: comparison of distinct pointer types ('typeof (iova) *' (aka 'unsigned long *') and 'typeof (length - 1) *' (aka 'unsigned int *'))

tree: https://github.com/luxis1999/iommufd iommufd-v5.16-rc3 head: 21c1bb93447d6cced2f486cdb68b92d11f2e664d commit: 4aa75d972a71aafba6e3b57ca91f6a04bdd37611 [23/25] vfio/pci: Add bind_iommufd() support config: i386-randconfig-r013-20211216 (https://download.01.org/0day-ci/archive/20211217/202112170238.6pX2L0DT-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project dd245bab9fbb364faa1581e4f92ba3119a872fba) 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 # https://github.com/luxis1999/iommufd/commit/4aa75d972a71aafba6e3b57ca91f6... git remote add luxis1999-iommufd https://github.com/luxis1999/iommufd git fetch --no-tags luxis1999-iommufd iommufd-v5.16-rc3 git checkout 4aa75d972a71aafba6e3b57ca91f6a04bdd37611 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/iommu/iommufd/ 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 >>): if (check_add_overflow(iova, length - 1, &last_iova)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/overflow.h:66:15: note: expanded from macro 'check_add_overflow' (void) (&__a == &__b); \ ~~~~ ^ ~~~~ drivers/iommu/iommufd/io_pagetable.c:1595:14: warning: comparison of distinct pointer types ('typeof (iova) *' (aka 'unsigned long *') and 'typeof (length - 1) *' (aka 'unsigned int *')) [-Wcompare-distinct-pointer-types] WARN_ON(check_add_overflow(iova, length - 1, &last_iova))) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/overflow.h:66:15: note: expanded from macro 'check_add_overflow' (void) (&__a == &__b); \ ~~~~ ^ ~~~~ include/asm-generic/bug.h:121:25: note: expanded from macro 'WARN_ON' int __ret_warn_on = !!(condition); \ ^~~~~~~~~ 2 warnings generated. Kconfig warnings: (for reference only) WARNING: unmet direct dependencies detected for IOMMUFD Depends on IOMMU_SUPPORT Selected by - VFIO_PCI_CORE && VFIO && PCI && MMU vim +1535 drivers/iommu/iommufd/io_pagetable.c b1baa437fe5478 Jason Gunthorpe 2021-11-11 1509 b1baa437fe5478 Jason Gunthorpe 2021-11-11 1510 /** b1baa437fe5478 Jason Gunthorpe 2021-11-11 1511 * iopt_access_pages - Return a list of pages under the iova b1baa437fe5478 Jason Gunthorpe 2021-11-11 1512 * b1baa437fe5478 Jason Gunthorpe 2021-11-11 1513 * Reads @npages starting at iova and returns the struct page * pointers. These b1baa437fe5478 Jason Gunthorpe 2021-11-11 1514 * can be kmap'd by the caller for CPU access. b1baa437fe5478 Jason Gunthorpe 2021-11-11 1515 * b1baa437fe5478 Jason Gunthorpe 2021-11-11 1516 * The caller must perform iopt_unaccess_pages() when done to balance this. b1baa437fe5478 Jason Gunthorpe 2021-11-11 1517 * b1baa437fe5478 Jason Gunthorpe 2021-11-11 1518 * iova can be unaligned from PAGE_SIZE. The first returned byte starts at b1baa437fe5478 Jason Gunthorpe 2021-11-11 1519 * page_to_phys(out_pages[0]) + (iova % PAGE_SIZE). The caller promises not b1baa437fe5478 Jason Gunthorpe 2021-11-11 1520 * to touch memory outside the requested iova subslice. b1baa437fe5478 Jason Gunthorpe 2021-11-11 1521 * b1baa437fe5478 Jason Gunthorpe 2021-11-11 1522 * FIXME: callers that need a DMA mapping via a sgl should create another b1baa437fe5478 Jason Gunthorpe 2021-11-11 1523 * interface to build the SGL efficiently b1baa437fe5478 Jason Gunthorpe 2021-11-11 1524 */ b1baa437fe5478 Jason Gunthorpe 2021-11-11 1525 int iopt_access_pages(struct io_pagetable *iopt, unsigned long iova, b1baa437fe5478 Jason Gunthorpe 2021-11-11 1526 size_t length, struct page **out_pages, bool write) b1baa437fe5478 Jason Gunthorpe 2021-11-11 1527 { b1baa437fe5478 Jason Gunthorpe 2021-11-11 1528 unsigned long cur_iova = iova; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1529 unsigned long last_iova; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1530 struct iopt_area *area; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1531 int rc; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1532 b1baa437fe5478 Jason Gunthorpe 2021-11-11 1533 if (!length) b1baa437fe5478 Jason Gunthorpe 2021-11-11 1534 return -EINVAL; b1baa437fe5478 Jason Gunthorpe 2021-11-11 @1535 if (check_add_overflow(iova, length - 1, &last_iova)) b1baa437fe5478 Jason Gunthorpe 2021-11-11 1536 return -EOVERFLOW; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1537 b1baa437fe5478 Jason Gunthorpe 2021-11-11 1538 down_read(&iopt->rwsem); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1539 for (area = iopt_area_iter_first(iopt, iova, last_iova); area; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1540 area = iopt_area_iter_next(area, iova, last_iova)) { b1baa437fe5478 Jason Gunthorpe 2021-11-11 1541 unsigned long last = min(last_iova, iopt_area_last_iova(area)); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1542 unsigned long last_index; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1543 unsigned long index; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1544 b1baa437fe5478 Jason Gunthorpe 2021-11-11 1545 /* Need contiguous areas in the access */ b1baa437fe5478 Jason Gunthorpe 2021-11-11 1546 if (iopt_area_iova(area) < cur_iova) { b1baa437fe5478 Jason Gunthorpe 2021-11-11 1547 rc = -EINVAL; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1548 goto out_remove; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1549 } b1baa437fe5478 Jason Gunthorpe 2021-11-11 1550 b1baa437fe5478 Jason Gunthorpe 2021-11-11 1551 index = iopt_iova_to_index(area, cur_iova); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1552 last_index = iopt_iova_to_index(area, last); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1553 rc = iopt_pages_add_user(area->pages, index, last_index, b1baa437fe5478 Jason Gunthorpe 2021-11-11 1554 out_pages, write); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1555 if (rc) b1baa437fe5478 Jason Gunthorpe 2021-11-11 1556 goto out_remove; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1557 if (last == last_iova) b1baa437fe5478 Jason Gunthorpe 2021-11-11 1558 break; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1559 /* b1baa437fe5478 Jason Gunthorpe 2021-11-11 1560 * Can't cross areas that are not aligned to the system page b1baa437fe5478 Jason Gunthorpe 2021-11-11 1561 * size with this API. b1baa437fe5478 Jason Gunthorpe 2021-11-11 1562 */ b1baa437fe5478 Jason Gunthorpe 2021-11-11 1563 if (cur_iova % PAGE_SIZE) { b1baa437fe5478 Jason Gunthorpe 2021-11-11 1564 rc = -EINVAL; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1565 goto out_remove; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1566 } b1baa437fe5478 Jason Gunthorpe 2021-11-11 1567 cur_iova = last + 1; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1568 out_pages += last_index - index; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1569 atomic_inc(&area->num_users); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1570 } b1baa437fe5478 Jason Gunthorpe 2021-11-11 1571 b1baa437fe5478 Jason Gunthorpe 2021-11-11 1572 up_read(&iopt->rwsem); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1573 return 0; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1574 b1baa437fe5478 Jason Gunthorpe 2021-11-11 1575 out_remove: b1baa437fe5478 Jason Gunthorpe 2021-11-11 1576 if (cur_iova != iova) b1baa437fe5478 Jason Gunthorpe 2021-11-11 1577 iopt_unaccess_pages(iopt, iova, cur_iova - iova); b1baa437fe5478 Jason Gunthorpe 2021-11-11 1578 return rc; b1baa437fe5478 Jason Gunthorpe 2021-11-11 1579 } b1baa437fe5478 Jason Gunthorpe 2021-11-11 1580 :::::: The code at line 1535 was first introduced by commit :::::: b1baa437fe5478bf8f79e53f49409b2f413ea27e iommufd: Data structure to provide IOVA to PFN mapping :::::: TO: Jason Gunthorpe <jgg(a)nvidia.com&gt; :::::: CC: Jason Gunthorpe <jgg(a)nvidia.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org