[Intel-gfx] [PATCH 4/4] drm/i915/guc: Verify hwconfig blob matches supported format

[kernel test robot]

Hi Jordan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on drm-tip/drm-tip drm-exynos/exynos-drm-next drm/drm-next tegra-drm/drm/tegra/for-next v5.17-rc3 next-20220207]
[cannot apply to airlied/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 '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Jordan-Justen/GuC-HWCONFIG-with-documentation/20220208-032950
base:   git://anongit.freedesktop.org/drm-intel for-linux-next
config: i386-buildonly-randconfig-r001-20220207 (https://download.01.org/0day-ci/archive/20220208/202202080648.8LUbxyNz-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0d8850ae2cae85d49bea6ae0799fa41c7202c05c)
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
        # https://github.com/0day-ci/linux/commit/c122b0dea958e76766ce9b4b9f34d2eed16fb566
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Jordan-Justen/GuC-HWCONFIG-with-documentation/20220208-032950
        git checkout c122b0dea958e76766ce9b4b9f34d2eed16fb566
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/i915/

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

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/i915/gt/uc/intel_guc_hwconfig.c:79:44: warning: mixing declarations and code is a C99 extension [-Wdeclaration-after-statement]
           struct drm_i915_query_hwconfig_blob_item *pos = hwconfig->ptr;
                                                     ^
   1 warning generated.


vim +79 drivers/gpu/drm/i915/gt/uc/intel_guc_hwconfig.c

    73	
    74	static int verify_hwconfig_blob(const struct intel_guc_hwconfig *hwconfig)
    75	{
    76		if (hwconfig->size % 4 != 0 || hwconfig->ptr == NULL)
    77			return -EINVAL;
    78	
  > 79		struct drm_i915_query_hwconfig_blob_item *pos = hwconfig->ptr;
    80		u32 remaining = (hwconfig->size / 4);
    81		while (remaining > 0) {
    82			if (remaining < 2)
    83				return -EINVAL;
    84			if (pos->length > remaining - 2)
    85				return -EINVAL;
    86			remaining -= 2 + pos->length;
    87			pos = (void *)&pos->data[pos->length];
    88		}
    89	
    90		DRM_INFO("hwconfig blob format appears valid\n");
    91		return 0;
    92	}
    93	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org