[kbuild-all] security/integrity/ima/ima_kexec.c:81:6: warning: no previous prototype for function 'ima_add_kexec_buffer'

Hi Lakshmi, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 368094df48e680fa51cedb68537408cfa64b788e commit: dce92f6b11c3174737bd65eaf933458909b633ff arm64: Enable passing IMA log to next kernel on kexec date: 3 months ago config: arm64-randconfig-r004-20210609 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project d2012d965d60c3258b3a69d024491698f8aec386) 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 arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout dce92f6b11c3174737bd65eaf933458909b633ff # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): void ima_add_kexec_buffer(struct kimage *image) ^ security/integrity/ima/ima_kexec.c:81:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void ima_add_kexec_buffer(struct kimage *image) ^ static 1 warning generated. vim +/ima_add_kexec_buffer +81 security/integrity/ima/ima_kexec.c 7b8589cc29e7c3 Mimi Zohar 2016-12-19 74 7b8589cc29e7c3 Mimi Zohar 2016-12-19 75 /* 7b8589cc29e7c3 Mimi Zohar 2016-12-19 76 * Called during kexec_file_load so that IMA can add a segment to the kexec 7b8589cc29e7c3 Mimi Zohar 2016-12-19 77 * image for the measurement list for the next kernel. 7b8589cc29e7c3 Mimi Zohar 2016-12-19 78 * 7b8589cc29e7c3 Mimi Zohar 2016-12-19 79 * This function assumes that kexec_mutex is held. 7b8589cc29e7c3 Mimi Zohar 2016-12-19 80 */ 7b8589cc29e7c3 Mimi Zohar 2016-12-19 @81 void ima_add_kexec_buffer(struct kimage *image) 7b8589cc29e7c3 Mimi Zohar 2016-12-19 82 { 7b8589cc29e7c3 Mimi Zohar 2016-12-19 83 struct kexec_buf kbuf = { .image = image, .buf_align = PAGE_SIZE, 7b8589cc29e7c3 Mimi Zohar 2016-12-19 84 .buf_min = 0, .buf_max = ULONG_MAX, 7b8589cc29e7c3 Mimi Zohar 2016-12-19 85 .top_down = true }; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 86 unsigned long binary_runtime_size; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 87 7b8589cc29e7c3 Mimi Zohar 2016-12-19 88 /* use more understandable variable names than defined in kbuf */ 7b8589cc29e7c3 Mimi Zohar 2016-12-19 89 void *kexec_buffer = NULL; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 90 size_t kexec_buffer_size; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 91 size_t kexec_segment_size; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 92 int ret; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 93 7b8589cc29e7c3 Mimi Zohar 2016-12-19 94 /* 7b8589cc29e7c3 Mimi Zohar 2016-12-19 95 * Reserve an extra half page of memory for additional measurements 7b8589cc29e7c3 Mimi Zohar 2016-12-19 96 * added during the kexec load. 7b8589cc29e7c3 Mimi Zohar 2016-12-19 97 */ 7b8589cc29e7c3 Mimi Zohar 2016-12-19 98 binary_runtime_size = ima_get_binary_runtime_size(); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 99 if (binary_runtime_size >= ULONG_MAX - PAGE_SIZE) 7b8589cc29e7c3 Mimi Zohar 2016-12-19 100 kexec_segment_size = ULONG_MAX; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 101 else 7b8589cc29e7c3 Mimi Zohar 2016-12-19 102 kexec_segment_size = ALIGN(ima_get_binary_runtime_size() + 7b8589cc29e7c3 Mimi Zohar 2016-12-19 103 PAGE_SIZE / 2, PAGE_SIZE); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 104 if ((kexec_segment_size == ULONG_MAX) || ca79b0c211af63 Arun KS 2018-12-28 105 ((kexec_segment_size >> PAGE_SHIFT) > totalram_pages() / 2)) { 7b8589cc29e7c3 Mimi Zohar 2016-12-19 106 pr_err("Binary measurement list too large.\n"); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 107 return; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 108 } 7b8589cc29e7c3 Mimi Zohar 2016-12-19 109 7b8589cc29e7c3 Mimi Zohar 2016-12-19 110 ima_dump_measurement_list(&kexec_buffer_size, &kexec_buffer, 7b8589cc29e7c3 Mimi Zohar 2016-12-19 111 kexec_segment_size); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 112 if (!kexec_buffer) { 7b8589cc29e7c3 Mimi Zohar 2016-12-19 113 pr_err("Not enough memory for the kexec measurement buffer.\n"); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 114 return; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 115 } 7b8589cc29e7c3 Mimi Zohar 2016-12-19 116 7b8589cc29e7c3 Mimi Zohar 2016-12-19 117 kbuf.buffer = kexec_buffer; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 118 kbuf.bufsz = kexec_buffer_size; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 119 kbuf.memsz = kexec_segment_size; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 120 ret = kexec_add_buffer(&kbuf); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 121 if (ret) { 7b8589cc29e7c3 Mimi Zohar 2016-12-19 122 pr_err("Error passing over kexec measurement buffer.\n"); 6d14c6517885fa Lakshmi Ramasubramanian 2021-02-04 123 vfree(kexec_buffer); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 124 return; 7b8589cc29e7c3 Mimi Zohar 2016-12-19 125 } 7b8589cc29e7c3 Mimi Zohar 2016-12-19 126 0c605158be3210 Lakshmi Ramasubramanian 2021-02-21 127 image->ima_buffer_addr = kbuf.mem; 0c605158be3210 Lakshmi Ramasubramanian 2021-02-21 128 image->ima_buffer_size = kexec_segment_size; f31e3386a4e92b Lakshmi Ramasubramanian 2021-02-04 129 image->ima_buffer = kexec_buffer; f31e3386a4e92b Lakshmi Ramasubramanian 2021-02-04 130 7b8589cc29e7c3 Mimi Zohar 2016-12-19 131 pr_debug("kexec measurement buffer for the loaded kernel at 0x%lx.\n", 7b8589cc29e7c3 Mimi Zohar 2016-12-19 132 kbuf.mem); 7b8589cc29e7c3 Mimi Zohar 2016-12-19 133 } 7b8589cc29e7c3 Mimi Zohar 2016-12-19 134 #endif /* IMA_KEXEC */ 7b8589cc29e7c3 Mimi Zohar 2016-12-19 135 :::::: The code at line 81 was first introduced by commit :::::: 7b8589cc29e7c35dcfd2d5138979f17b48f90110 ima: on soft reboot, save the measurement list :::::: TO: Mimi Zohar <zohar(a)linux.vnet.ibm.com&gt; :::::: CC: Linus Torvalds <torvalds(a)linux-foundation.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org