Hi Catalin, FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant. tree: https://github.com/ammarfaizi2/linux-block arm64/linux/devel/kmalloc-minalign-v2-wip head: 168a8e28785ff49842163cb8cd2aebd5ed90e6a4 commit: 8ddce10ef74e9c1aaeed401f89f4a17b36a55c5c [8/10] mm: slab: Use new_kmalloc_cache() for initialising the INDEX_NODE config: powerpc-icon_defconfig compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 791a7ae1ba3efd6bca96338e10ffde557ba83920) 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 # install powerpc cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://github.com/ammarfaizi2/linux-block/commit/8ddce10ef74e9c1aaeed401f89f4a17b36a55c5c git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block git fetch --no-tags ammarfaizi2-block arm64/linux/devel/kmalloc-minalign-v2-wip git checkout 8ddce10ef74e9c1aaeed401f89f4a17b36a55c5c # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> mm/slab_common.c:659:27: warning: no previous prototype for function 'create_kmalloc_cache' [-Wmissing-prototypes] struct kmem_cache *__init create_kmalloc_cache(const char *name, ^ mm/slab_common.c:659:1: note: declare 'static' if the function is not intended to be used outside of this translation unit struct kmem_cache *__init create_kmalloc_cache(const char *name, ^ static 1 warning generated. vim +/create_kmalloc_cache +659 mm/slab_common.c 45530c4474d258 Christoph Lameter 2012-11-28 658 55de8b9c60f2f6 Alexey Dobriyan 2018-04-05 @659 struct kmem_cache *__init create_kmalloc_cache(const char *name, 55de8b9c60f2f6 Alexey Dobriyan 2018-04-05 660 unsigned int size, slab_flags_t flags, 55de8b9c60f2f6 Alexey Dobriyan 2018-04-05 661 unsigned int useroffset, unsigned int usersize) 45530c4474d258 Christoph Lameter 2012-11-28 662 { 45530c4474d258 Christoph Lameter 2012-11-28 663 struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT); 45530c4474d258 Christoph Lameter 2012-11-28 664 45530c4474d258 Christoph Lameter 2012-11-28 665 if (!s) 45530c4474d258 Christoph Lameter 2012-11-28 666 panic("Out of memory when creating slab %s\n", name); 45530c4474d258 Christoph Lameter 2012-11-28 667 6c0c21adc742a2 David Windsor 2017-06-10 668 create_boot_cache(s, name, size, flags, useroffset, usersize); 928501344fc645 Andrey Konovalov 2021-02-25 669 kasan_cache_create_kmalloc(s); 45530c4474d258 Christoph Lameter 2012-11-28 670 list_add(&s->list, &slab_caches); 45530c4474d258 Christoph Lameter 2012-11-28 671 s->refcount = 1; 45530c4474d258 Christoph Lameter 2012-11-28 672 return s; 45530c4474d258 Christoph Lameter 2012-11-28 673 } 45530c4474d258 Christoph Lameter 2012-11-28 674 :::::: The code at line 659 was first introduced by commit :::::: 55de8b9c60f2f6da9bf5c9144020882d07e62296 slab: make create_kmalloc_cache() work with 32-bit sizes :::::: TO: Alexey Dobriyan :::::: CC: Linus Torvalds -- 0-DAY CI Kernel Test Service https://01.org/lkp