Re: [PATCH v2 3/3] kasan: fix krealloc handling for tag-based mode

From: kbuild test robot
Date: Wed Jan 02 2019 - 17:15:13 EST


Hi Andrey,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on next-20190102]
[cannot apply to v4.20]
[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/Andrey-Konovalov/kasan-tag-based-mode-fixes/20190103-050707
config: x86_64-randconfig-x016-201900 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64

All warnings (new ones prefixed by >>):

mm/kasan/common.c: In function 'kasan_krealloc':
>> mm/kasan/common.c:525:3: warning: ignoring return value of 'kasan_kmalloc_large', declared with attribute warn_unused_result [-Wunused-result]
kasan_kmalloc_large(object, size, flags);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> mm/kasan/common.c:527:3: warning: ignoring return value of 'kasan_kmalloc', declared with attribute warn_unused_result [-Wunused-result]
kasan_kmalloc(page->slab_cache, object, size, flags, true);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

vim +/kasan_kmalloc_large +525 mm/kasan/common.c

514
515 void kasan_krealloc(const void *object, size_t size, gfp_t flags)
516 {
517 struct page *page;
518
519 if (unlikely(object == ZERO_SIZE_PTR))
520 return;
521
522 page = virt_to_head_page(object);
523
524 if (unlikely(!PageSlab(page)))
> 525 kasan_kmalloc_large(object, size, flags);
526 else
> 527 kasan_kmalloc(page->slab_cache, object, size, flags, true);
528 }
529

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation

Attachment: .config.gz
Description: application/gzip