Hi Alexey, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [cannot apply to mmotm/master v4.14 next-20171124] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Alexey-Dobriyan/slab-make-kmalloc_index-return-unsigned-int/20171125-035138 reproduce: # apt-get install sparse make ARCH=x86_64 allmodconfig make C=1 CF=-D__CHECK_ENDIAN__ sparse warnings: (new ones prefixed by >>) vim +361 mm/kasan/kasan.c 7ed2f9e6 Alexander Potapenko 2016-03-25 338 5d094e12 Alexey Dobriyan 2017-11-24 339 void kasan_cache_create(struct kmem_cache *cache, unsigned int *size, d50112ed Alexey Dobriyan 2017-11-15 340 slab_flags_t *flags) 7ed2f9e6 Alexander Potapenko 2016-03-25 341 { 5d094e12 Alexey Dobriyan 2017-11-24 342 unsigned int orig_size = *size; 7ed2f9e6 Alexander Potapenko 2016-03-25 343 int redzone_adjust; 80a9201a Alexander Potapenko 2016-07-28 344 7ed2f9e6 Alexander Potapenko 2016-03-25 345 /* Add alloc meta. */ 7ed2f9e6 Alexander Potapenko 2016-03-25 346 cache->kasan_info.alloc_meta_offset = *size; 7ed2f9e6 Alexander Potapenko 2016-03-25 347 *size += sizeof(struct kasan_alloc_meta); 7ed2f9e6 Alexander Potapenko 2016-03-25 348 7ed2f9e6 Alexander Potapenko 2016-03-25 349 /* Add free meta. */ 5f0d5a3a Paul E. McKenney 2017-01-18 350 if (cache->flags & SLAB_TYPESAFE_BY_RCU || cache->ctor || 7ed2f9e6 Alexander Potapenko 2016-03-25 351 cache->object_size < sizeof(struct kasan_free_meta)) { 7ed2f9e6 Alexander Potapenko 2016-03-25 352 cache->kasan_info.free_meta_offset = *size; 7ed2f9e6 Alexander Potapenko 2016-03-25 353 *size += sizeof(struct kasan_free_meta); 7ed2f9e6 Alexander Potapenko 2016-03-25 354 } 7ed2f9e6 Alexander Potapenko 2016-03-25 355 redzone_adjust = optimal_redzone(cache->object_size) - 7ed2f9e6 Alexander Potapenko 2016-03-25 356 (*size - cache->object_size); 80a9201a Alexander Potapenko 2016-07-28 357 7ed2f9e6 Alexander Potapenko 2016-03-25 358 if (redzone_adjust > 0) 7ed2f9e6 Alexander Potapenko 2016-03-25 359 *size += redzone_adjust; 80a9201a Alexander Potapenko 2016-07-28 360 80a9201a Alexander Potapenko 2016-07-28 @361 *size = min(KMALLOC_MAX_SIZE, max(*size, cache->object_size + 7ed2f9e6 Alexander Potapenko 2016-03-25 362 optimal_redzone(cache->object_size))); 80a9201a Alexander Potapenko 2016-07-28 363 80a9201a Alexander Potapenko 2016-07-28 364 /* 80a9201a Alexander Potapenko 2016-07-28 365 * If the metadata doesn't fit, don't enable KASAN at all. 80a9201a Alexander Potapenko 2016-07-28 366 */ 80a9201a Alexander Potapenko 2016-07-28 367 if (*size <= cache->kasan_info.alloc_meta_offset || 80a9201a Alexander Potapenko 2016-07-28 368 *size <= cache->kasan_info.free_meta_offset) { 80a9201a Alexander Potapenko 2016-07-28 369 cache->kasan_info.alloc_meta_offset = 0; 80a9201a Alexander Potapenko 2016-07-28 370 cache->kasan_info.free_meta_offset = 0; 80a9201a Alexander Potapenko 2016-07-28 371 *size = orig_size; 80a9201a Alexander Potapenko 2016-07-28 372 return; 80a9201a Alexander Potapenko 2016-07-28 373 } 80a9201a Alexander Potapenko 2016-07-28 374 80a9201a Alexander Potapenko 2016-07-28 375 *flags |= SLAB_KASAN; 7ed2f9e6 Alexander Potapenko 2016-03-25 376 } 7ed2f9e6 Alexander Potapenko 2016-03-25 377 :::::: The code at line 361 was first introduced by commit :::::: 80a9201a5965f4715d5c09790862e0df84ce0614 mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB :::::: TO: Alexander Potapenko <glider@xxxxxxxxxx> :::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
