tree: https://github.com/0day-ci/linux/commits/UPDATE-20211009-062812/Kumar-Kartikeya-Dwivedi/bpf-Silence-Coverity-warning-for-find_kfunc_desc_btf/20211009-010928 head: aff5b53e62a423701f59205b644916bae36c96c3 commit: aff5b53e62a423701f59205b644916bae36c96c3 bpf: Silence Coverity warning for find_kfunc_desc_btf date: 6 hours ago config: microblaze-buildonly-randconfig-r003-20211008 (attached as .config) compiler: microblaze-linux-gcc (GCC) 11.2.0 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 # https://github.com/0day-ci/linux/commit/aff5b53e62a423701f59205b644916bae36c96c3 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review UPDATE-20211009-062812/Kumar-Kartikeya-Dwivedi/bpf-Silence-Coverity-warning-for-find_kfunc_desc_btf/20211009-010928 git checkout aff5b53e62a423701f59205b644916bae36c96c3 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=microblaze If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): kernel/bpf/verifier.c: In function 'find_kfunc_desc_btf': >> kernel/bpf/verifier.c:1776:21: error: unused variable 'kfunc_btf' [-Werror=unused-variable] 1776 | struct btf *kfunc_btf; | ^~~~~~~~~ cc1: all warnings being treated as errors vim +/kfunc_btf +1776 kernel/bpf/verifier.c 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1771 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1772 static struct btf *find_kfunc_desc_btf(struct bpf_verifier_env *env, 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1773 u32 func_id, s16 offset, 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1774 struct module **btf_modp) 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1775 { 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 @1776 struct btf *kfunc_btf; 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1777 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1778 if (offset) { 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1779 if (offset < 0) { 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1780 /* In the future, this can be allowed to increase limit 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1781 * of fd index into fd_array, interpreted as u16. 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1782 */ 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1783 verbose(env, "negative offset disallowed for kernel module function call\n"); 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1784 return ERR_PTR(-EINVAL); 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1785 } 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1786 aff5b53e62a42370 Kumar Kartikeya Dwivedi 2021-10-09 1787 return __find_kfunc_desc_btf(env, offset, btf_modp); 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1788 } 2357672c54c3f748 Kumar Kartikeya Dwivedi 2021-10-02 1789 return btf_vmlinux ?: ERR_PTR(-ENOENT); e6ac2450d6dee312 Martin KaFai Lau 2021-03-24 1790 } e6ac2450d6dee312 Martin KaFai Lau 2021-03-24 1791 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org