Am Freitag, 18. September 2020, 15:02:17 CEST schrieb kernel test robot: Hi, > All errors (new ones prefixed by >>): > >> drivers/char/lrng/lrng_chacha20.c:33:8: error: structure variable > >> 'chacha20' with 'latent_entropy' attribute has a non-integer field > >> 'block' > 33 | struct chacha20_state chacha20 __latent_entropy; > > | ^~~~~~~~~~~~~~ > > # > https://github.com/0day-ci/linux/commit/ecb964754fd80cca434d6d2ad6db8f28a15 > 92fa1 git remote add linux-review https://github.com/0day-ci/linux > git fetch --no-tags linux-review > Stephan-M-ller/dev-random-a-new-approach/20200918-181505 git checkout > ecb964754fd80cca434d6d2ad6db8f28a1592fa1 > vim +33 drivers/char/lrng/lrng_chacha20.c > > 27 > 28 /* > 29 * Have a static memory blocks for the ChaCha20 DRNG instance to > avoid calling 30 * kmalloc too early in the boot cycle. For subsequent > allocation requests, 31 * such as per-NUMA-node DRNG instances, kmalloc > will be used. 32 */ > > > 33 struct chacha20_state chacha20 __latent_entropy; I do not think this report is valid. The following definitions apply: struct chacha20_state { struct chacha20_block block; }; struct chacha20_block { u32 constants[4]; union { #define CHACHA_KEY_SIZE_WORDS (CHACHA_KEY_SIZE / sizeof(u32)) u32 u[CHACHA_KEY_SIZE_WORDS]; u8 b[CHACHA_KEY_SIZE]; } key; u32 counter; u32 nonce[3]; }; This implies that struct chacha20_state and thus the chacha20 variable is a linear buffer with in total 4 + 8 + 1 + 3 = 16 32-bit integers which are at least aligned on a 32-bit boundary and are designated as u32 integers. Please let me know if I need to make a tweak to the definitions to convince the code analyzer it is a flat linear buffer consisting of integers and thus to understand the structure correctly. Thanks a lot. Ciao Stephan
