Hi Dan, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on awilliam-vfio/next] [also build test WARNING on rdma/for-next linus/master v5.19-rc5 next-20220707] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Dan-Carpenter/vfio-mlx5-clean-up-overflow-check/20220707-225657 base: https://github.com/awilliam/linux-vfio.git next config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220708/202207080331.FTVSHxW8-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-3) 11.3.0 reproduce (this is a W=1 build): # https://github.com/intel-lab-lkp/linux/commit/44607f8f3817e1af6622db7d70ad5bc457b8f203 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Dan-Carpenter/vfio-mlx5-clean-up-overflow-check/20220707-225657 git checkout 44607f8f3817e1af6622db7d70ad5bc457b8f203 # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/vfio/pci/mlx5/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): In file included from include/linux/device.h:29, from drivers/vfio/pci/mlx5/main.c:6: drivers/vfio/pci/mlx5/main.c: In function 'mlx5vf_resume_write': >> include/linux/overflow.h:67:22: warning: comparison of distinct pointer types lacks a cast 67 | (void) (&__a == &__b); \ | ^~ drivers/vfio/pci/mlx5/main.c:282:13: note: in expansion of macro 'check_add_overflow' 282 | check_add_overflow(len, (unsigned long)*pos, &requested_length)) | ^~~~~~~~~~~~~~~~~~ include/linux/overflow.h:68:22: warning: comparison of distinct pointer types lacks a cast 68 | (void) (&__a == __d); \ | ^~ drivers/vfio/pci/mlx5/main.c:282:13: note: in expansion of macro 'check_add_overflow' 282 | check_add_overflow(len, (unsigned long)*pos, &requested_length)) | ^~~~~~~~~~~~~~~~~~ vim +67 include/linux/overflow.h 9b80e4c4ddaca35 Kees Cook 2020-08-12 54 f0907827a8a9152 Rasmus Villemoes 2018-05-08 55 /* f0907827a8a9152 Rasmus Villemoes 2018-05-08 56 * For simplicity and code hygiene, the fallback code below insists on f0907827a8a9152 Rasmus Villemoes 2018-05-08 57 * a, b and *d having the same type (similar to the min() and max() f0907827a8a9152 Rasmus Villemoes 2018-05-08 58 * macros), whereas gcc's type-generic overflow checkers accept f0907827a8a9152 Rasmus Villemoes 2018-05-08 59 * different types. Hence we don't just make check_add_overflow an f0907827a8a9152 Rasmus Villemoes 2018-05-08 60 * alias for __builtin_add_overflow, but add type checks similar to f0907827a8a9152 Rasmus Villemoes 2018-05-08 61 * below. f0907827a8a9152 Rasmus Villemoes 2018-05-08 62 */ 9b80e4c4ddaca35 Kees Cook 2020-08-12 63 #define check_add_overflow(a, b, d) __must_check_overflow(({ \ f0907827a8a9152 Rasmus Villemoes 2018-05-08 64 typeof(a) __a = (a); \ f0907827a8a9152 Rasmus Villemoes 2018-05-08 65 typeof(b) __b = (b); \ f0907827a8a9152 Rasmus Villemoes 2018-05-08 66 typeof(d) __d = (d); \ f0907827a8a9152 Rasmus Villemoes 2018-05-08 @67 (void) (&__a == &__b); \ f0907827a8a9152 Rasmus Villemoes 2018-05-08 68 (void) (&__a == __d); \ f0907827a8a9152 Rasmus Villemoes 2018-05-08 69 __builtin_add_overflow(__a, __b, __d); \ 9b80e4c4ddaca35 Kees Cook 2020-08-12 70 })) f0907827a8a9152 Rasmus Villemoes 2018-05-08 71 -- 0-DAY CI Kernel Test Service https://01.org/lkp
