tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   f359287765c04711ff54fbd11645271d8e5ff763
commit: b0310c2f09bbe8aebefb97ed67949a3a7092aca6 USB: use genalloc for USB HCs with local memory
config: m68k-randconfig-r002-20200602 (attached as .config)
compiler: m68k-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout b0310c2f09bbe8aebefb97ed67949a3a7092aca6
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k 

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

All errors (new ones prefixed by >>, old ones prefixed by <<):

sound/core/pcm_native.c: In function 'snd_pcm_lib_default_mmap':
<<                  from sound/core/pcm_native.c:45:
>> sound/core/pcm_native.c:3412:24: error: implicit declaration of function 'pgprot_writecombine'; did you mean 'dma_free_writecombine'? [-Werror=implicit-function-declaration]
3412 |   area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
|                        ^~~~~~~~~~~~~~~~~~~
|                        dma_free_writecombine
sound/core/pcm_native.c:3412:24: error: incompatible types when assigning to type 'pgprot_t' {aka 'struct <anonymous>'} from type 'int'
cc1: some warnings being treated as errors

# https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b0310c2f09bbe8aebefb97ed67949a3a7092aca6
git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git remote update linus
git checkout b0310c2f09bbe8aebefb97ed67949a3a7092aca6
vim +3412 sound/core/pcm_native.c

^1da177e4c3f41 Linus Torvalds        2005-04-16  3393  
^1da177e4c3f41 Linus Torvalds        2005-04-16  3394  /*
^1da177e4c3f41 Linus Torvalds        2005-04-16  3395   * mmap the DMA buffer on RAM
^1da177e4c3f41 Linus Torvalds        2005-04-16  3396   */
30b771cf8c3120 Takashi Iwai          2014-10-30  3397  
30b771cf8c3120 Takashi Iwai          2014-10-30  3398  /**
30b771cf8c3120 Takashi Iwai          2014-10-30  3399   * snd_pcm_lib_default_mmap - Default PCM data mmap function
30b771cf8c3120 Takashi Iwai          2014-10-30  3400   * @substream: PCM substream
30b771cf8c3120 Takashi Iwai          2014-10-30  3401   * @area: VMA
30b771cf8c3120 Takashi Iwai          2014-10-30  3402   *
30b771cf8c3120 Takashi Iwai          2014-10-30  3403   * This is the default mmap handler for PCM data.  When mmap pcm_ops is NULL,
30b771cf8c3120 Takashi Iwai          2014-10-30  3404   * this function is invoked implicitly.
30b771cf8c3120 Takashi Iwai          2014-10-30  3405   */
18a2b962337047 Takashi Iwai          2011-09-28  3406  int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
877211f5e1b119 Takashi Iwai          2005-11-17  3407  			     struct vm_area_struct *area)
^1da177e4c3f41 Linus Torvalds        2005-04-16  3408  {
314e51b9851b4f Konstantin Khlebnikov 2012-10-08  3409  	area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
a5606f85611267 Takashi Iwai          2013-10-24  3410  #ifdef CONFIG_GENERIC_ALLOCATOR
055032142c42d2 Nicolin Chen          2013-10-23  3411  	if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV_IRAM) {
055032142c42d2 Nicolin Chen          2013-10-23 @3412  		area->vm_page_prot = pgprot_writecombine(area->vm_page_prot);
055032142c42d2 Nicolin Chen          2013-10-23  3413  		return remap_pfn_range(area, area->vm_start,
055032142c42d2 Nicolin Chen          2013-10-23  3414  				substream->dma_buffer.addr >> PAGE_SHIFT,
055032142c42d2 Nicolin Chen          2013-10-23  3415  				area->vm_end - area->vm_start, area->vm_page_prot);
055032142c42d2 Nicolin Chen          2013-10-23  3416  	}
a5606f85611267 Takashi Iwai          2013-10-24  3417  #endif /* CONFIG_GENERIC_ALLOCATOR */
49d776ffb50f2e Takashi Iwai          2014-10-24  3418  #ifndef CONFIG_X86 /* for avoiding warnings arch/x86/mm/pat.c */
abe594c2cf55b4 Geert Uytterhoeven    2017-07-09  3419  	if (IS_ENABLED(CONFIG_HAS_DMA) && !substream->ops->page &&
657b1989dacf58 Takashi Iwai          2009-11-26  3420  	    substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV)
657b1989dacf58 Takashi Iwai          2009-11-26  3421  		return dma_mmap_coherent(substream->dma_buffer.dev.dev,
657b1989dacf58 Takashi Iwai          2009-11-26  3422  					 area,
657b1989dacf58 Takashi Iwai          2009-11-26  3423  					 substream->runtime->dma_area,
657b1989dacf58 Takashi Iwai          2009-11-26  3424  					 substream->runtime->dma_addr,
9066ae7ff5d89c Stefan Roese          2018-03-26  3425  					 substream->runtime->dma_bytes);
49d776ffb50f2e Takashi Iwai          2014-10-24  3426  #endif /* CONFIG_X86 */
657b1989dacf58 Takashi Iwai          2009-11-26  3427  	/* mmap with fault handler */
657b1989dacf58 Takashi Iwai          2009-11-26  3428  	area->vm_ops = &snd_pcm_vm_ops_data_fault;
^1da177e4c3f41 Linus Torvalds        2005-04-16  3429  	return 0;
^1da177e4c3f41 Linus Torvalds        2005-04-16  3430  }
18a2b962337047 Takashi Iwai          2011-09-28  3431  EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap);
^1da177e4c3f41 Linus Torvalds        2005-04-16  3432  

:::::: The code at line 3412 was first introduced by commit
:::::: 055032142c42d2821c4aa617915292d6a08d56fc ALSA: Add SoC on-chip internal ram support for DMA buffer allocation

:::::: TO: Nicolin Chen <b42378@freescale.com>
:::::: CC: Takashi Iwai <tiwai@suse.de>

---
0-DAY CI Kernel Test Service, Intel Corporation
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