Re: [PATCH v5 21/25] drm/xe/madvise: Skip vma invalidation if mem attr are unchanged

[kernel test robot <lkp@intel.com>]

Hi Himal,

kernel test robot noticed the following build warnings:

[auto build test WARNING on next-20250730]
[cannot apply to drm-xe/drm-xe-next linus/master v6.16 v6.16-rc7 v6.16-rc6 v6.16]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Himal-Prasad-Ghimiray/drm-gpuvm-Pass-map-arguments-through-a-struct/20250731-003813
base:   next-20250730
patch link:    https://lore.kernel.org/r/20250730130050.1001648-22-himal.prasad.ghimiray%40intel.com
patch subject: [PATCH v5 21/25] drm/xe/madvise: Skip vma invalidation if mem attr are unchanged
config: arm-randconfig-004-20250731 (https://download.01.org/0day-ci/archive/20250731/202507310458.N20slFKu-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 8f09b03aebb71c154f3bbe725c29e3f47d37c26e)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250731/202507310458.N20slFKu-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202507310458.N20slFKu-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/xe/xe_vm_madvise.c:200:4: warning: variable 'tile_mask' is uninitialized when used here [-Wuninitialized]
     200 |                         tile_mask |= xe_svm_ranges_zap_ptes_in_range(vm,
         |                         ^~~~~~~~~
   drivers/gpu/drm/xe/xe_vm_madvise.c:184:18: note: initialize the variable 'tile_mask' to silence this warning
     184 |         u8 id, tile_mask;
         |                         ^
         |                          = '\0'
   1 warning generated.


vim +/tile_mask +200 drivers/gpu/drm/xe/xe_vm_madvise.c

   179	
   180	static u8 xe_zap_ptes_in_madvise_range(struct xe_vm *vm, u64 start, u64 end)
   181	{
   182		struct drm_gpuva *gpuva;
   183		struct xe_tile *tile;
   184		u8 id, tile_mask;
   185	
   186		lockdep_assert_held_write(&vm->lock);
   187	
   188		/* Wait for pending binds */
   189		if (dma_resv_wait_timeout(xe_vm_resv(vm), DMA_RESV_USAGE_BOOKKEEP,
   190					  false, MAX_SCHEDULE_TIMEOUT) <= 0)
   191			XE_WARN_ON(1);
   192	
   193		drm_gpuvm_for_each_va_range(gpuva, &vm->gpuvm, start, end) {
   194			struct xe_vma *vma = gpuva_to_vma(gpuva);
   195	
   196			if (vma->skip_invalidation || xe_vma_is_null(vma))
   197				continue;
   198	
   199			if (xe_vma_is_cpu_addr_mirror(vma)) {
 > 200				tile_mask |= xe_svm_ranges_zap_ptes_in_range(vm,
   201									      xe_vma_start(vma),
   202									      xe_vma_end(vma));
   203			} else {
   204				for_each_tile(tile, vm->xe, id) {
   205					if (xe_pt_zap_ptes(tile, vma)) {
   206						tile_mask |= BIT(id);
   207	
   208					/*
   209					 * WRITE_ONCE pairs with READ_ONCE
   210					 * in xe_vm_has_valid_gpu_mapping()
   211					 */
   212					WRITE_ONCE(vma->tile_invalidated,
   213						   vma->tile_invalidated | BIT(id));
   214					}
   215				}
   216			}
   217		}
   218	
   219		return tile_mask;
   220	}
   221	

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