Hi Jeffrey, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on char-misc/char-misc-testing] [also build test WARNING on soc/for-next linus/master v5.7-rc6 next-20200518] [cannot apply to linux/master] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Jeffrey-Hugo/Qualcomm-Cloud-AI-1... base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git 57c76221d5af648c8355a55c09b050c5d8d38189 config: xtensa-allyesconfig (attached as .config) compiler: xtensa-linux-gcc (GCC) 9.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=xtensa If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>, old ones prefixed by <<): In file included from include/linux/kernel.h:11, from include/linux/list.h:9, from include/linux/swait.h:5, from include/linux/completion.h:12, from drivers/misc/qaic/qaic_data.c:5: include/linux/scatterlist.h: In function 'sg_set_buf': arch/xtensa/include/asm/page.h:193:9: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] 193 | ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr) | ^~ include/linux/compiler.h:78:42: note: in definition of macro 'unlikely' 78 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ include/linux/scatterlist.h:143:2: note: in expansion of macro 'BUG_ON' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~ arch/xtensa/include/asm/page.h:201:32: note: in expansion of macro 'pfn_valid' 201 | #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) | ^~~~~~~~~ include/linux/scatterlist.h:143:10: note: in expansion of macro 'virt_addr_valid' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~~~~~~~~~~ In file included from ./arch/xtensa/include/generated/asm/bug.h:1, from include/linux/bug.h:5, from include/linux/thread_info.h:12, from include/asm-generic/preempt.h:5, from ./arch/xtensa/include/generated/asm/preempt.h:1, from include/linux/preempt.h:78, from include/linux/spinlock.h:51, from include/linux/swait.h:7, from include/linux/completion.h:12, from drivers/misc/qaic/qaic_data.c:5: include/linux/dma-mapping.h: In function 'dma_map_resource': arch/xtensa/include/asm/page.h:193:9: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] 193 | ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr) | ^~ include/asm-generic/bug.h:139:27: note: in definition of macro 'WARN_ON_ONCE' 139 | int __ret_warn_once = !!(condition); | ^~~~~~~~~ include/linux/dma-mapping.h:352:19: note: in expansion of macro 'pfn_valid' 352 | if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr)))) | ^~~~~~~~~ In file included from include/linux/shm.h:6, from include/linux/sched.h:16, from include/linux/ratelimit.h:6, from include/linux/dev_printk.h:16, from include/linux/device.h:15, from include/linux/dma-mapping.h:7, from drivers/misc/qaic/qaic_data.c:6: drivers/misc/qaic/qaic_data.c: In function 'reserve_pages': arch/xtensa/include/asm/page.h:193:9: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] 193 | ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr) | ^~ 103 | if (!pfn_valid(pfn)) | ^~~~~~~~~ vim +/pfn_valid +103 drivers/misc/qaic/qaic_data.c 94 95 static int reserve_pages(unsigned long start_pfn, unsigned long nr_pages, 96 bool reserve) 97 { 98 unsigned long pfn; 99 unsigned long end_pfn = start_pfn + nr_pages; 100 struct page *page; 101 102 for (pfn = start_pfn; pfn < end_pfn; pfn++) { 104 return -EINVAL; 105 page = pfn_to_page(pfn); 106 if (reserve) 107 SetPageReserved(page); 108 else 109 ClearPageReserved(page); 110 } 111 return 0; 112 } 113 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org