Hi Arvind, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on efi/next] [also build test WARNING on next-20200429] [cannot apply to v5.7-rc3] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Arvind-Sankar/efi-some-cleanups-refactoring-for-efi-next/20200430-051025 base: https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git next config: arm-defconfig (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 1ccde533425a4ba9d379510206ad680ff9702129) reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot All warnings (new ones prefixed by >>): >> drivers/firmware/efi/libstub/efi-stub.c:220:7: warning: variable 'si' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (status != EFI_SUCCESS) { ^~~~~~~~~~~~~~~~~~~~~ drivers/firmware/efi/libstub/efi-stub.c:339:19: note: uninitialized use occurs here free_screen_info(si); ^~ drivers/firmware/efi/libstub/efi-stub.c:220:3: note: remove the 'if' if its condition is always false if (status != EFI_SUCCESS) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/firmware/efi/libstub/efi-stub.c:212:7: warning: variable 'si' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (status != EFI_SUCCESS) { ^~~~~~~~~~~~~~~~~~~~~ drivers/firmware/efi/libstub/efi-stub.c:339:19: note: uninitialized use occurs here free_screen_info(si); ^~ drivers/firmware/efi/libstub/efi-stub.c:212:3: note: remove the 'if' if its condition is always false if (status != EFI_SUCCESS) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/firmware/efi/libstub/efi-stub.c:161:24: note: initialize the variable 'si' to silence this warning struct screen_info *si; ^ = NULL 2 warnings generated. vim +220 drivers/firmware/efi/libstub/efi-stub.c 119 120 /* 121 * This function handles the architcture specific differences between arm and 122 * arm64 regarding where the kernel image must be loaded and any memory that 123 * must be reserved. On failure it is required to free all 124 * all allocations it has made. 125 */ 126 efi_status_t handle_kernel_image(unsigned long *image_addr, 127 unsigned long *image_size, 128 unsigned long *reserve_addr, 129 unsigned long *reserve_size, 130 unsigned long dram_base, 131 efi_loaded_image_t *image); 132 133 asmlinkage void __noreturn efi_enter_kernel(unsigned long entrypoint, 134 unsigned long fdt_addr, 135 unsigned long fdt_size); 136 137 /* 138 * EFI entry point for the arm/arm64 EFI stubs. This is the entrypoint 139 * that is described in the PE/COFF header. Most of the code is the same 140 * for both archictectures, with the arch-specific code provided in the 141 * handle_kernel_image() function. 142 */ 143 efi_status_t efi_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg) 144 { 145 efi_loaded_image_t *image; 146 efi_status_t status; 147 unsigned long image_addr; 148 unsigned long image_size = 0; 149 unsigned long dram_base; 150 /* addr/point and size pairs for memory management*/ 151 unsigned long initrd_addr = 0; 152 unsigned long initrd_size = 0; 153 unsigned long fdt_addr = 0; /* Original DTB */ 154 unsigned long fdt_size = 0; 155 char *cmdline_ptr = NULL; 156 int cmdline_size = 0; 157 efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID; 158 unsigned long reserve_addr = 0; 159 unsigned long reserve_size = 0; 160 enum efi_secureboot_mode secure_boot; 161 struct screen_info *si; 162 efi_properties_table_t *prop_tbl; 163 unsigned long max_addr; 164 165 efi_system_table = sys_table_arg; 166 167 /* Check if we were booted by the EFI firmware */ 168 if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) { 169 status = EFI_INVALID_PARAMETER; 170 goto fail; 171 } 172 173 status = check_platform_features(); 174 if (status != EFI_SUCCESS) 175 goto fail; 176 177 /* 178 * Get a handle to the loaded image protocol. This is used to get 179 * information about the running image, such as size and the command 180 * line. 181 */ 182 status = efi_system_table->boottime->handle_protocol(handle, 183 &loaded_image_proto, (void *)&image); 184 if (status != EFI_SUCCESS) { 185 pr_efi_err("Failed to get loaded image protocol\n"); 186 goto fail; 187 } 188 189 dram_base = get_dram_base(); 190 if (dram_base == EFI_ERROR) { 191 pr_efi_err("Failed to find DRAM base\n"); 192 status = EFI_LOAD_ERROR; 193 goto fail; 194 } 195 196 /* 197 * Get the command line from EFI, using the LOADED_IMAGE 198 * protocol. We are going to copy the command line into the 199 * device tree, so this can be allocated anywhere. 200 */ 201 cmdline_ptr = efi_convert_cmdline(image, &cmdline_size, ULONG_MAX); 202 if (!cmdline_ptr) { 203 pr_efi_err("getting command line via LOADED_IMAGE_PROTOCOL\n"); 204 status = EFI_OUT_OF_RESOURCES; 205 goto fail; 206 } 207 208 if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) || 209 IS_ENABLED(CONFIG_CMDLINE_FORCE) || 210 cmdline_size == 0) { 211 status = efi_parse_options(CONFIG_CMDLINE); 212 if (status != EFI_SUCCESS) { 213 pr_efi_err("Failed to parse options\n"); 214 goto fail_free_cmdline; 215 } 216 } 217 218 if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && cmdline_size > 0) { 219 status = efi_parse_options(cmdline_ptr); > 220 if (status != EFI_SUCCESS) { 221 pr_efi_err("Failed to parse options\n"); 222 goto fail_free_cmdline; 223 } 224 } 225 226 pr_efi("Booting Linux Kernel...\n"); 227 228 si = setup_graphics(); 229 230 status = handle_kernel_image(&image_addr, &image_size, 231 &reserve_addr, 232 &reserve_size, 233 dram_base, image); 234 if (status != EFI_SUCCESS) { 235 pr_efi_err("Failed to relocate kernel\n"); 236 goto fail_free_cmdline; 237 } 238 239 efi_retrieve_tpm2_eventlog(); 240 241 /* Ask the firmware to clear memory on unclean shutdown */ 242 efi_enable_reset_attack_mitigation(); 243 244 secure_boot = efi_get_secureboot(); 245 246 /* 247 * Unauthenticated device tree data is a security hazard, so ignore 248 * 'dtb=' unless UEFI Secure Boot is disabled. We assume that secure 249 * boot is enabled if we can't determine its state. 250 */ 251 if (!IS_ENABLED(CONFIG_EFI_ARMSTUB_DTB_LOADER) || 252 secure_boot != efi_secureboot_mode_disabled) { 253 if (strstr(cmdline_ptr, "dtb=")) 254 pr_efi("Ignoring DTB from command line.\n"); 255 } else { 256 status = efi_load_dtb(image, &fdt_addr, &fdt_size); 257 258 if (status != EFI_SUCCESS) { 259 pr_efi_err("Failed to load device tree!\n"); 260 goto fail_free_image; 261 } 262 } 263 264 if (fdt_addr) { 265 pr_efi("Using DTB from command line\n"); 266 } else { 267 /* Look for a device tree configuration table entry. */ 268 fdt_addr = (uintptr_t)get_fdt(&fdt_size); 269 if (fdt_addr) 270 pr_efi("Using DTB from configuration table\n"); 271 } 272 273 if (!fdt_addr) 274 pr_efi("Generating empty DTB\n"); 275 276 if (!efi_noinitrd) { 277 max_addr = efi_get_max_initrd_addr(dram_base, image_addr); 278 status = efi_load_initrd(image, &initrd_addr, &initrd_size, max_addr); 279 if (status != EFI_SUCCESS) 280 pr_efi_err("Failed to load initrd!\n"); 281 } 282 283 efi_random_get_seed(); 284 285 /* 286 * If the NX PE data feature is enabled in the properties table, we 287 * should take care not to create a virtual mapping that changes the 288 * relative placement of runtime services code and data regions, as 289 * they may belong to the same PE/COFF executable image in memory. 290 * The easiest way to achieve that is to simply use a 1:1 mapping. 291 */ 292 prop_tbl = get_efi_config_table(EFI_PROPERTIES_TABLE_GUID); 293 flat_va_mapping = prop_tbl && 294 (prop_tbl->memory_protection_attribute & 295 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA); 296 297 /* hibernation expects the runtime regions to stay in the same place */ 298 if (!IS_ENABLED(CONFIG_HIBERNATION) && !efi_nokaslr && !flat_va_mapping) { 299 /* 300 * Randomize the base of the UEFI runtime services region. 301 * Preserve the 2 MB alignment of the region by taking a 302 * shift of 21 bit positions into account when scaling 303 * the headroom value using a 32-bit random value. 304 */ 305 static const u64 headroom = EFI_RT_VIRTUAL_LIMIT - 306 EFI_RT_VIRTUAL_BASE - 307 EFI_RT_VIRTUAL_SIZE; 308 u32 rnd; 309 310 status = efi_get_random_bytes(sizeof(rnd), (u8 *)&rnd); 311 if (status == EFI_SUCCESS) { 312 virtmap_base = EFI_RT_VIRTUAL_BASE + 313 (((headroom >> 21) * rnd) >> (32 - 21)); 314 } 315 } 316 317 install_memreserve_table(); 318 319 status = allocate_new_fdt_and_exit_boot(handle, &fdt_addr, 320 efi_get_max_fdt_addr(dram_base), 321 initrd_addr, initrd_size, 322 cmdline_ptr, fdt_addr, fdt_size); 323 if (status != EFI_SUCCESS) 324 goto fail_free_initrd; 325 326 efi_enter_kernel(image_addr, fdt_addr, fdt_totalsize((void *)fdt_addr)); 327 /* not reached */ 328 329 fail_free_initrd: 330 pr_efi_err("Failed to update FDT and exit boot services\n"); 331 332 efi_free(initrd_size, initrd_addr); 333 efi_free(fdt_size, fdt_addr); 334 335 fail_free_image: 336 efi_free(image_size, image_addr); 337 efi_free(reserve_size, reserve_addr); 338 fail_free_cmdline: 339 free_screen_info(si); 340 efi_free(cmdline_size, (unsigned long)cmdline_ptr); 341 fail: 342 return status; 343 } 344 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org