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'data->pgd[tbl]' drivers/iommu/io-pgtable-dart.c:252 dart_map_pages() warn: array off by one? 'data->pgd[tbl]' drivers/iommu/io-pgtable-dart.c 174 static dart_iopte *dart_get_last(struct dart_io_pgtable *data, unsigned long iova) 175 { 176 dart_iopte pte, *ptep; 177 int level = data->levels; 178 int tbl = dart_get_index(data, iova, level); 179 180 if (tbl > (1 << data->tbl_bits)) ^ It does look like this should be >=. 181 return NULL; 182 --> 183 ptep = data->pgd[tbl]; data->pgd[] has BIT(2) elements. The data->tbl_bits value is set in dart_alloc_pgtable() and it has a check if (tbl_bits > max_tbl_bits) which ensures that it is not more than 2. I don't think dart_get_index() can actually return more than 3 so maybe the check can just be removed? 184 if (!ptep) 185 return NULL; 186 187 while (--level > 1) { 188 ptep += dart_get_index(data, iova, level); 189 pte = READ_ONCE(*ptep); 190 191 /* Valid entry? */ 192 if (!pte) 193 return NULL; 194 195 /* Deref to get next level table */ 196 ptep = iopte_deref(pte, data); 197 } 198 199 return ptep; 200 } regards, dan carpenter