Hi Eric,

I love your patch! Perhaps something to improve:

[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next drm-tip/drm-tip linus/master v5.8-rc3 next-20200703]
[cannot apply to drm/drm-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use  as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Eric-Anholt/drm-msm-Garbage-collect-unused-resource-_len-fields/20200630-022449
base:   git://anongit.freedesktop.org/drm-intel for-linux-next
config: arm64-randconfig-r031-20200703 (attached as .config)
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project ca464639a1c9dd3944eb055ffd2796e8c2e7639f)
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
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 

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

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/msm/msm_drv.c:123:15: warning: no previous prototype for function '_msm_ioremap' [-Wmissing-prototypes]
   void __iomem *_msm_ioremap(struct platform_device *pdev, const char *name,
                 ^
   drivers/gpu/drm/msm/msm_drv.c:123:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void __iomem *_msm_ioremap(struct platform_device *pdev, const char *name,
   ^
   static 
   1 warning generated.

vim +/_msm_ioremap +123 drivers/gpu/drm/msm/msm_drv.c

   122	
 > 123	void __iomem *_msm_ioremap(struct platform_device *pdev, const char *name,
   124				   const char *dbgname, bool quiet)
   125	{
   126		struct resource *res;
   127		unsigned long size;
   128		void __iomem *ptr;
   129	
   130		if (name)
   131			res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
   132		else
   133			res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
   134	
   135		if (!res) {
   136			if (!quiet)
   137				DRM_DEV_ERROR(&pdev->dev, "failed to get memory resource: %s\n", name);
   138			return ERR_PTR(-EINVAL);
   139		}
   140	
   141		size = resource_size(res);
   142	
   143		ptr = devm_ioremap(&pdev->dev, res->start, size);
   144		if (!ptr) {
   145			if (!quiet)
   146				DRM_DEV_ERROR(&pdev->dev, "failed to ioremap: %s\n", name);
   147			return ERR_PTR(-ENOMEM);
   148		}
   149	
   150		if (reglog)
   151			printk(KERN_DEBUG "IO:region %s %p %08lx\n", dbgname, ptr, size);
   152	
   153		return ptr;
   154	}
   155	

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