Messages in this thread | | | Date | Tue, 1 Feb 2022 09:34:03 +0800 | From | kernel test robot <> | Subject | [jgunthorpe:iommufd 23/29] include/linux/overflow.h:66:22: warning: comparison of distinct pointer types lacks a cast |
| |
tree: https://github.com/jgunthorpe/linux iommufd head: 086f3f78da96ed1f11c2ac71115bb46e940e141e commit: b944c7f08293cd7b049be615e67622f5d0d74cfb [23/29] iommufd: Data structure to provide IOVA to PFN mapping config: powerpc-allyesconfig (https://download.01.org/0day-ci/archive/20220201/202202010939.dIipJCeV-lkp@intel.com/config) compiler: powerpc-linux-gcc (GCC) 11.2.0 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/jgunthorpe/linux/commit/b944c7f08293cd7b049be615e67622f5d0d74cfb git remote add jgunthorpe https://github.com/jgunthorpe/linux git fetch --no-tags jgunthorpe iommufd git checkout b944c7f08293cd7b049be615e67622f5d0d74cfb # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=powerpc SHELL=/bin/bash drivers/iommu/iommufd/ fs/nfs/
If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@intel.com>
All warnings (new ones prefixed by >>):
In file included from include/linux/mm.h:30, from include/linux/scatterlist.h:8, from include/linux/iommu.h:10, from drivers/iommu/iommufd/io_pagetable.c:27: drivers/iommu/iommufd/io_pagetable.c: In function 'iopt_access_pages': >> include/linux/overflow.h:66:22: warning: comparison of distinct pointer types lacks a cast 66 | (void) (&__a == &__b); \ | ^~ drivers/iommu/iommufd/io_pagetable.c:488:13: note: in expansion of macro 'check_add_overflow' 488 | if (check_add_overflow(iova, length - 1, &last_iova)) | ^~~~~~~~~~~~~~~~~~ In file included from arch/powerpc/include/asm/bug.h:149, from include/linux/bug.h:5, from arch/powerpc/include/asm/cmpxchg.h:8, from arch/powerpc/include/asm/atomic.h:11, from include/linux/atomic.h:7, from include/linux/cpumask.h:13, from include/linux/smp.h:13, from include/linux/lockdep.h:14, from drivers/iommu/iommufd/io_pagetable.c:26: drivers/iommu/iommufd/io_pagetable.c: In function 'iopt_unaccess_pages': >> include/linux/overflow.h:66:22: warning: comparison of distinct pointer types lacks a cast 66 | (void) (&__a == &__b); \ | ^~ include/asm-generic/bug.h:121:32: note: in definition of macro 'WARN_ON' 121 | int __ret_warn_on = !!(condition); \ | ^~~~~~~~~ drivers/iommu/iommufd/io_pagetable.c:548:21: note: in expansion of macro 'check_add_overflow' 548 | WARN_ON(check_add_overflow(iova, length - 1, &last_iova))) | ^~~~~~~~~~~~~~~~~~
vim +66 include/linux/overflow.h
9b80e4c4ddaca3 Kees Cook 2020-08-12 53 f0907827a8a915 Rasmus Villemoes 2018-05-08 54 /* f0907827a8a915 Rasmus Villemoes 2018-05-08 55 * For simplicity and code hygiene, the fallback code below insists on f0907827a8a915 Rasmus Villemoes 2018-05-08 56 * a, b and *d having the same type (similar to the min() and max() f0907827a8a915 Rasmus Villemoes 2018-05-08 57 * macros), whereas gcc's type-generic overflow checkers accept f0907827a8a915 Rasmus Villemoes 2018-05-08 58 * different types. Hence we don't just make check_add_overflow an f0907827a8a915 Rasmus Villemoes 2018-05-08 59 * alias for __builtin_add_overflow, but add type checks similar to f0907827a8a915 Rasmus Villemoes 2018-05-08 60 * below. f0907827a8a915 Rasmus Villemoes 2018-05-08 61 */ 9b80e4c4ddaca3 Kees Cook 2020-08-12 62 #define check_add_overflow(a, b, d) __must_check_overflow(({ \ f0907827a8a915 Rasmus Villemoes 2018-05-08 63 typeof(a) __a = (a); \ f0907827a8a915 Rasmus Villemoes 2018-05-08 64 typeof(b) __b = (b); \ f0907827a8a915 Rasmus Villemoes 2018-05-08 65 typeof(d) __d = (d); \ f0907827a8a915 Rasmus Villemoes 2018-05-08 @66 (void) (&__a == &__b); \ f0907827a8a915 Rasmus Villemoes 2018-05-08 67 (void) (&__a == __d); \ f0907827a8a915 Rasmus Villemoes 2018-05-08 68 __builtin_add_overflow(__a, __b, __d); \ 9b80e4c4ddaca3 Kees Cook 2020-08-12 69 })) f0907827a8a915 Rasmus Villemoes 2018-05-08 70
:::::: The code at line 66 was first introduced by commit :::::: f0907827a8a9152aedac2833ed1b674a7b2a44f2 compiler.h: enable builtin overflow checkers and add fallback code
:::::: TO: Rasmus Villemoes <linux@rasmusvillemoes.dk> :::::: CC: Kees Cook <keescook@chromium.org>
--- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
| |