Hi Jason, kernel test robot noticed the following build warnings: [auto build test WARNING on kvms390/next] [cannot apply to s390/features linus/master v6.8-rc1 next-20240125] [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/Jason-J-Herne/s390-ap-Externalize-AP-bus-specific-bitmap-reading-function/20240126-223952 base: https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git next patch link: https://lore.kernel.org/r/20240126143533.14043-4-jjherne%40linux.ibm.com patch subject: [PATCH 3/3] s390/vfio-ap: Add write support to sysfs attr ap_config config: s390-defconfig (https://download.01.org/0day-ci/archive/20240128/202401282141.A8V47yFI-lkp@xxxxxxxxx/config) compiler: s390-linux-gcc (GCC) 13.2.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240128/202401282141.A8V47yFI-lkp@xxxxxxxxx/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@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202401282141.A8V47yFI-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from include/linux/cpumask.h:12, from include/linux/smp.h:13, from include/linux/lockdep.h:14, from include/linux/spinlock.h:63, from include/linux/mmzone.h:8, from include/linux/gfp.h:7, from include/linux/mm.h:7, from include/linux/scatterlist.h:8, from include/linux/iommu.h:10, from include/linux/vfio.h:12, from drivers/s390/crypto/vfio_ap_ops.c:12: In function 'bitmap_copy', inlined from 'ap_matrix_copy' at drivers/s390/crypto/vfio_ap_ops.c:1593:2, inlined from 'ap_config_store' at drivers/s390/crypto/vfio_ap_ops.c:1616:2: >> include/linux/bitmap.h:245:17: warning: 'memcpy' reading 32 bytes from a region of size 0 [-Wstringop-overread] 245 | memcpy(dst, src, len); | ^~~~~~~~~~~~~~~~~~~~~ In function 'ap_config_store': cc1: note: source object is likely at address zero In function 'bitmap_copy', inlined from 'ap_matrix_copy' at drivers/s390/crypto/vfio_ap_ops.c:1594:2, inlined from 'ap_config_store' at drivers/s390/crypto/vfio_ap_ops.c:1616:2: >> include/linux/bitmap.h:245:17: warning: 'memcpy' reading 32 bytes from a region of size 0 [-Wstringop-overread] 245 | memcpy(dst, src, len); | ^~~~~~~~~~~~~~~~~~~~~ In function 'ap_config_store': cc1: note: source object is likely at address zero In function 'bitmap_copy', inlined from 'ap_matrix_copy' at drivers/s390/crypto/vfio_ap_ops.c:1595:2, inlined from 'ap_config_store' at drivers/s390/crypto/vfio_ap_ops.c:1616:2: >> include/linux/bitmap.h:245:17: warning: 'memcpy' reading 32 bytes from a region of size 0 [-Wstringop-overread] 245 | memcpy(dst, src, len); | ^~~~~~~~~~~~~~~~~~~~~ In function 'ap_config_store': cc1: note: source object is likely at address zero vim +/memcpy +245 include/linux/bitmap.h ^1da177e4c3f41 Linus Torvalds 2005-04-16 236 ^1da177e4c3f41 Linus Torvalds 2005-04-16 237 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, 8b4daad52fee77 Rasmus Villemoes 2015-02-12 238 unsigned int nbits) ^1da177e4c3f41 Linus Torvalds 2005-04-16 239 { 8b4daad52fee77 Rasmus Villemoes 2015-02-12 240 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 3e7e5baaaba780 Alexander Lobakin 2022-06-24 241 3e7e5baaaba780 Alexander Lobakin 2022-06-24 242 if (small_const_nbits(nbits)) 3e7e5baaaba780 Alexander Lobakin 2022-06-24 243 *dst = *src; 3e7e5baaaba780 Alexander Lobakin 2022-06-24 244 else ^1da177e4c3f41 Linus Torvalds 2005-04-16 @245 memcpy(dst, src, len); ^1da177e4c3f41 Linus Torvalds 2005-04-16 246 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 247 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
