Hi David, I love your patch! Perhaps something to improve: [auto build test WARNING on linux/master] [also build test WARNING on driver-core/driver-core-testing next-20210125] [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] url: https://github.com/0day-ci/linux/commits/David-Hildenbrand/drivers-base-m... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 2ab38c17aac10bf55ab3efde4c4db3893d8691d2 config: x86_64-randconfig-s031-20210201 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-215-g0fb77bb6-dirty # https://github.com/0day-ci/linux/commit/614341d29c44f8965a604b9fd5d09eb0b... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review David-Hildenbrand/drivers-base-memory-clarify-some-memory-block-properties/20210201-185331 git checkout 614341d29c44f8965a604b9fd5d09eb0b652864c # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64 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/base/memory.c: In function 'init_memory_block': 573 | unsigned long start_pfn; | ^~~~~~~~~ vim +/start_pfn +573 drivers/base/memory.c 96b2c0fc8e74a6 Nathan Fontenot 2013-06-04 569 40ba2cde77e764 Wei Yang 2020-06-23 570 static int init_memory_block(unsigned long block_id, unsigned long state) e4619c857d1d76 Nathan Fontenot 2010-10-19 571 { 0c2c99b1b8ab5d Nathan Fontenot 2011-01-20 572 struct memory_block *mem; e4619c857d1d76 Nathan Fontenot 2010-10-19 @573 unsigned long start_pfn; e4619c857d1d76 Nathan Fontenot 2010-10-19 574 int ret = 0; e4619c857d1d76 Nathan Fontenot 2010-10-19 575 dd625285910d3c David Hildenbrand 2019-07-18 576 mem = find_memory_block_by_id(block_id); db051a0dac13db David Hildenbrand 2019-07-18 577 if (mem) { db051a0dac13db David Hildenbrand 2019-07-18 578 put_device(&mem->dev); db051a0dac13db David Hildenbrand 2019-07-18 579 return -EEXIST; db051a0dac13db David Hildenbrand 2019-07-18 580 } 0c2c99b1b8ab5d Nathan Fontenot 2011-01-20 581 mem = kzalloc(sizeof(*mem), GFP_KERNEL); e4619c857d1d76 Nathan Fontenot 2010-10-19 582 if (!mem) e4619c857d1d76 Nathan Fontenot 2010-10-19 583 return -ENOMEM; e4619c857d1d76 Nathan Fontenot 2010-10-19 584 1811582587c43b David Hildenbrand 2019-07-18 585 mem->start_section_nr = block_id * sections_per_block; e4619c857d1d76 Nathan Fontenot 2010-10-19 586 mem->state = state; d33601644cd3b0 Nathan Fontenot 2011-01-20 587 start_pfn = section_nr_to_pfn(mem->start_section_nr); d84f2f5a755208 David Hildenbrand 2019-09-23 588 mem->nid = NUMA_NO_NODE; e4619c857d1d76 Nathan Fontenot 2010-10-19 589 0c2c99b1b8ab5d Nathan Fontenot 2011-01-20 590 ret = register_memory(mem); 0c2c99b1b8ab5d Nathan Fontenot 2011-01-20 591 0c2c99b1b8ab5d Nathan Fontenot 2011-01-20 592 return ret; 0c2c99b1b8ab5d Nathan Fontenot 2011-01-20 593 } 0c2c99b1b8ab5d Nathan Fontenot 2011-01-20 594 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org