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-100-driver/20200519-221821
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@intel.com>

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)
|         ^~
>> drivers/misc/qaic/qaic_data.c:103:8: note: in expansion of macro 'pfn_valid'
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++) {
 > 103			if (!pfn_valid(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
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