Hi Kees,

I love your patch! Yet something to improve:

[auto build test ERROR on linus/master]
[cannot apply to v5.4-rc2 next-20191010]
[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/Kees-Cook/dma-mapping-Move-vmap-address-checks-into-dma_map_single/20191005-073954
config: sh-magicpanelr2_defconfig (attached as .config)
compiler: sh4-linux-gcc (GCC) 7.4.0
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
        GCC_VERSION=7.4.0 make.cross ARCH=sh 

If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from arch/sh/include/asm/bug.h:112:0,
                    from include/linux/bug.h:5,
                    from include/linux/thread_info.h:12,
                    from include/asm-generic/preempt.h:5,
                    from ./arch/sh/include/generated/asm/preempt.h:1,
                    from include/linux/preempt.h:78,
                    from include/linux/spinlock.h:51,
                    from include/linux/seqlock.h:36,
                    from include/linux/time.h:6,
                    from include/linux/stat.h:19,
                    from include/linux/module.h:10,
                    from arch/sh/kernel/io.c:8:
   include/linux/dma-mapping.h: In function 'dma_map_single_attrs':
>> include/linux/dma-mapping.h:588:9: error: format '%lu' expects argument of type 'long unsigned int', but argument 4 has type 'size_t {aka unsigned int}' [-Werror=format=]
            "%s %s: driver maps %lu bytes from vmalloc area\n",
            ^
   include/asm-generic/bug.h:92:17: note: in definition of macro '__WARN_printf'
      __warn_printk(arg);     \
                    ^~~
   include/asm-generic/bug.h:155:3: note: in expansion of macro 'WARN'
      WARN(1, format);    \
      ^~~~
   include/linux/dma-mapping.h:587:6: note: in expansion of macro 'WARN_ONCE'
     if (WARN_ONCE(is_vmalloc_addr(ptr),
         ^~~~~~~~~
   cc1: all warnings being treated as errors

vim +588 include/linux/dma-mapping.h

   582	
   583	static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
   584			size_t size, enum dma_data_direction dir, unsigned long attrs)
   585	{
   586		/* DMA must never operate on areas that might be remapped. */
   587		if (WARN_ONCE(is_vmalloc_addr(ptr),
 > 588			      "%s %s: driver maps %lu bytes from vmalloc area\n",
   589			      dev ? dev_driver_string(dev) : "unknown driver",
   590			      dev ? dev_name(dev) : "unknown device", size))
   591			return DMA_MAPPING_ERROR;
   592	
   593		debug_dma_map_single(dev, ptr, size);
   594		return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
   595				size, dir, attrs);
   596	}
   597	

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