1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * crash.c - kernel crash support code. 4 * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com> 5 */ 6 7 #include <linux/buildid.h> 8 #include <linux/crash_core.h> 9 #include <linux/init.h> 10 #include <linux/utsname.h> 11 #include <linux/vmalloc.h> 12 #include <linux/sizes.h> 13 14 #include <asm/page.h> 15 #include <asm/sections.h> 16 17 #include <crypto/sha1.h> 18 19 #include "kallsyms_internal.h" 20 21 /* vmcoreinfo stuff */ 22 unsigned char *vmcoreinfo_data; 23 size_t vmcoreinfo_size; 24 u32 *vmcoreinfo_note; 25 26 /* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */ 27 static unsigned char *vmcoreinfo_data_safecopy; 28 29 /* 30 * parsing the "crashkernel" commandline 31 * 32 * this code is intended to be called from architecture specific code 33 */ 34 35 36 /* 37 * This function parses command lines in the format 38 * 39 * crashkernel=ramsize-range:size[,...][@offset] 40 * 41 * The function returns 0 on success and -EINVAL on failure. 42 */ 43 static int __init parse_crashkernel_mem(char *cmdline, 44 unsigned long long system_ram, 45 unsigned long long *crash_size, 46 unsigned long long *crash_base) 47 { 48 char *cur = cmdline, *tmp; 49 unsigned long long total_mem = system_ram; 50 51 /* 52 * Firmware sometimes reserves some memory regions for its own use, 53 * so the system memory size is less than the actual physical memory 54 * size. Work around this by rounding up the total size to 128M, 55 * which is enough for most test cases. 56 */ 57 total_mem = roundup(total_mem, SZ_128M); 58 59 /* for each entry of the comma-separated list */ 60 do { 61 unsigned long long start, end = ULLONG_MAX, size; 62 63 /* get the start of the range */ 64 start = memparse(cur, &tmp); 65 if (cur == tmp) { 66 pr_warn("crashkernel: Memory value expected\n"); 67 return -EINVAL; 68 } 69 cur = tmp; 70 if (*cur != '-') { 71 pr_warn("crashkernel: '-' expected\n"); 72 return -EINVAL; 73 } 74 cur++; 75 76 /* if no ':' is here, than we read the end */ 77 if (*cur != ':') { 78 end = memparse(cur, &tmp); 79 if (cur == tmp) { 80 pr_warn("crashkernel: Memory value expected\n"); 81 return -EINVAL; 82 } 83 cur = tmp; 84 if (end <= start) { 85 pr_warn("crashkernel: end <= start\n"); 86 return -EINVAL; 87 } 88 } 89 90 if (*cur != ':') { 91 pr_warn("crashkernel: ':' expected\n"); 92 return -EINVAL; 93 } 94 cur++; 95 96 size = memparse(cur, &tmp); 97 if (cur == tmp) { 98 pr_warn("Memory value expected\n"); 99 return -EINVAL; 100 } 101 cur = tmp; 102 if (size >= total_mem) { 103 pr_warn("crashkernel: invalid size\n"); 104 return -EINVAL; 105 } 106 107 /* match ? */ 108 if (total_mem >= start && total_mem < end) { 109 *crash_size = size; 110 break; 111 } 112 } while (*cur++ == ','); 113 114 if (*crash_size > 0) { 115 while (*cur && *cur != ' ' && *cur != '@') 116 cur++; 117 if (*cur == '@') { 118 cur++; 119 *crash_base = memparse(cur, &tmp); 120 if (cur == tmp) { 121 pr_warn("Memory value expected after '@'\n"); 122 return -EINVAL; 123 } 124 } 125 } else 126 pr_info("crashkernel size resulted in zero bytes\n"); 127 128 return 0; 129 } 130 131 /* 132 * That function parses "simple" (old) crashkernel command lines like 133 * 134 * crashkernel=size[@offset] 135 * 136 * It returns 0 on success and -EINVAL on failure. 137 */ 138 static int __init parse_crashkernel_simple(char *cmdline, 139 unsigned long long *crash_size, 140 unsigned long long *crash_base) 141 { 142 char *cur = cmdline; 143 144 *crash_size = memparse(cmdline, &cur); 145 if (cmdline == cur) { 146 pr_warn("crashkernel: memory value expected\n"); 147 return -EINVAL; 148 } 149 150 if (*cur == '@') 151 *crash_base = memparse(cur+1, &cur); 152 else if (*cur != ' ' && *cur != '\0') { 153 pr_warn("crashkernel: unrecognized char: %c\n", *cur); 154 return -EINVAL; 155 } 156 157 return 0; 158 } 159 160 #define SUFFIX_HIGH 0 161 #define SUFFIX_LOW 1 162 #define SUFFIX_NULL 2 163 static __initdata char *suffix_tbl[] = { 164 [SUFFIX_HIGH] = ",high", 165 [SUFFIX_LOW] = ",low", 166 [SUFFIX_NULL] = NULL, 167 }; 168 169 /* 170 * That function parses "suffix" crashkernel command lines like 171 * 172 * crashkernel=size,[high|low] 173 * 174 * It returns 0 on success and -EINVAL on failure. 175 */ 176 static int __init parse_crashkernel_suffix(char *cmdline, 177 unsigned long long *crash_size, 178 const char *suffix) 179 { 180 char *cur = cmdline; 181 182 *crash_size = memparse(cmdline, &cur); 183 if (cmdline == cur) { 184 pr_warn("crashkernel: memory value expected\n"); 185 return -EINVAL; 186 } 187 188 /* check with suffix */ 189 if (strncmp(cur, suffix, strlen(suffix))) { 190 pr_warn("crashkernel: unrecognized char: %c\n", *cur); 191 return -EINVAL; 192 } 193 cur += strlen(suffix); 194 if (*cur != ' ' && *cur != '\0') { 195 pr_warn("crashkernel: unrecognized char: %c\n", *cur); 196 return -EINVAL; 197 } 198 199 return 0; 200 } 201 202 static __init char *get_last_crashkernel(char *cmdline, 203 const char *name, 204 const char *suffix) 205 { 206 char *p = cmdline, *ck_cmdline = NULL; 207 208 /* find crashkernel and use the last one if there are more */ 209 p = strstr(p, name); 210 while (p) { 211 char *end_p = strchr(p, ' '); 212 char *q; 213 214 if (!end_p) 215 end_p = p + strlen(p); 216 217 if (!suffix) { 218 int i; 219 220 /* skip the one with any known suffix */ 221 for (i = 0; suffix_tbl[i]; i++) { 222 q = end_p - strlen(suffix_tbl[i]); 223 if (!strncmp(q, suffix_tbl[i], 224 strlen(suffix_tbl[i]))) 225 goto next; 226 } 227 ck_cmdline = p; 228 } else { 229 q = end_p - strlen(suffix); 230 if (!strncmp(q, suffix, strlen(suffix))) 231 ck_cmdline = p; 232 } 233 next: 234 p = strstr(p+1, name); 235 } 236 237 return ck_cmdline; 238 } 239 240 static int __init __parse_crashkernel(char *cmdline, 241 unsigned long long system_ram, 242 unsigned long long *crash_size, 243 unsigned long long *crash_base, 244 const char *name, 245 const char *suffix) 246 { 247 char *first_colon, *first_space; 248 char *ck_cmdline; 249 250 BUG_ON(!crash_size || !crash_base); 251 *crash_size = 0; 252 *crash_base = 0; 253 254 ck_cmdline = get_last_crashkernel(cmdline, name, suffix); 255 if (!ck_cmdline) 256 return -ENOENT; 257 258 ck_cmdline += strlen(name); 259 260 if (suffix) 261 return parse_crashkernel_suffix(ck_cmdline, crash_size, 262 suffix); 263 /* 264 * if the commandline contains a ':', then that's the extended 265 * syntax -- if not, it must be the classic syntax 266 */ 267 first_colon = strchr(ck_cmdline, ':'); 268 first_space = strchr(ck_cmdline, ' '); 269 if (first_colon && (!first_space || first_colon < first_space)) 270 return parse_crashkernel_mem(ck_cmdline, system_ram, 271 crash_size, crash_base); 272 273 return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base); 274 } 275 276 /* 277 * That function is the entry point for command line parsing and should be 278 * called from the arch-specific code. 279 */ 280 int __init parse_crashkernel(char *cmdline, 281 unsigned long long system_ram, 282 unsigned long long *crash_size, 283 unsigned long long *crash_base) 284 { 285 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, 286 "crashkernel=", NULL); 287 } 288 289 int __init parse_crashkernel_high(char *cmdline, 290 unsigned long long system_ram, 291 unsigned long long *crash_size, 292 unsigned long long *crash_base) 293 { 294 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, 295 "crashkernel=", suffix_tbl[SUFFIX_HIGH]); 296 } 297 298 int __init parse_crashkernel_low(char *cmdline, 299 unsigned long long system_ram, 300 unsigned long long *crash_size, 301 unsigned long long *crash_base) 302 { 303 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, 304 "crashkernel=", suffix_tbl[SUFFIX_LOW]); 305 } 306 307 /* 308 * Add a dummy early_param handler to mark crashkernel= as a known command line 309 * parameter and suppress incorrect warnings in init/main.c. 310 */ 311 static int __init parse_crashkernel_dummy(char *arg) 312 { 313 return 0; 314 } 315 early_param("crashkernel", parse_crashkernel_dummy); 316 317 Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, 318 void *data, size_t data_len) 319 { 320 struct elf_note *note = (struct elf_note *)buf; 321 322 note->n_namesz = strlen(name) + 1; 323 note->n_descsz = data_len; 324 note->n_type = type; 325 buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word)); 326 memcpy(buf, name, note->n_namesz); 327 buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word)); 328 memcpy(buf, data, data_len); 329 buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word)); 330 331 return buf; 332 } 333 334 void final_note(Elf_Word *buf) 335 { 336 memset(buf, 0, sizeof(struct elf_note)); 337 } 338 339 static void update_vmcoreinfo_note(void) 340 { 341 u32 *buf = vmcoreinfo_note; 342 343 if (!vmcoreinfo_size) 344 return; 345 buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data, 346 vmcoreinfo_size); 347 final_note(buf); 348 } 349 350 void crash_update_vmcoreinfo_safecopy(void *ptr) 351 { 352 if (ptr) 353 memcpy(ptr, vmcoreinfo_data, vmcoreinfo_size); 354 355 vmcoreinfo_data_safecopy = ptr; 356 } 357 358 void crash_save_vmcoreinfo(void) 359 { 360 if (!vmcoreinfo_note) 361 return; 362 363 /* Use the safe copy to generate vmcoreinfo note if have */ 364 if (vmcoreinfo_data_safecopy) 365 vmcoreinfo_data = vmcoreinfo_data_safecopy; 366 367 vmcoreinfo_append_str("CRASHTIME=%lld\n", ktime_get_real_seconds()); 368 update_vmcoreinfo_note(); 369 } 370 371 void vmcoreinfo_append_str(const char *fmt, ...) 372 { 373 va_list args; 374 char buf[0x50]; 375 size_t r; 376 377 va_start(args, fmt); 378 r = vscnprintf(buf, sizeof(buf), fmt, args); 379 va_end(args); 380 381 r = min(r, (size_t)VMCOREINFO_BYTES - vmcoreinfo_size); 382 383 memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r); 384 385 vmcoreinfo_size += r; 386 387 WARN_ONCE(vmcoreinfo_size == VMCOREINFO_BYTES, 388 "vmcoreinfo data exceeds allocated size, truncating"); 389 } 390 391 /* 392 * provide an empty default implementation here -- architecture 393 * code may override this 394 */ 395 void __weak arch_crash_save_vmcoreinfo(void) 396 {} 397 398 phys_addr_t __weak paddr_vmcoreinfo_note(void) 399 { 400 return __pa(vmcoreinfo_note); 401 } 402 EXPORT_SYMBOL(paddr_vmcoreinfo_note); 403 404 static int __init crash_save_vmcoreinfo_init(void) 405 { 406 vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL); 407 if (!vmcoreinfo_data) { 408 pr_warn("Memory allocation for vmcoreinfo_data failed\n"); 409 return -ENOMEM; 410 } 411 412 vmcoreinfo_note = alloc_pages_exact(VMCOREINFO_NOTE_SIZE, 413 GFP_KERNEL | __GFP_ZERO); 414 if (!vmcoreinfo_note) { 415 free_page((unsigned long)vmcoreinfo_data); 416 vmcoreinfo_data = NULL; 417 pr_warn("Memory allocation for vmcoreinfo_note failed\n"); 418 return -ENOMEM; 419 } 420 421 VMCOREINFO_OSRELEASE(init_uts_ns.name.release); 422 VMCOREINFO_BUILD_ID(); 423 VMCOREINFO_PAGESIZE(PAGE_SIZE); 424 425 VMCOREINFO_SYMBOL(init_uts_ns); 426 VMCOREINFO_OFFSET(uts_namespace, name); 427 VMCOREINFO_SYMBOL(node_online_map); 428 #ifdef CONFIG_MMU 429 VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir); 430 #endif 431 VMCOREINFO_SYMBOL(_stext); 432 VMCOREINFO_SYMBOL(vmap_area_list); 433 434 #ifndef CONFIG_NUMA 435 VMCOREINFO_SYMBOL(mem_map); 436 VMCOREINFO_SYMBOL(contig_page_data); 437 #endif 438 #ifdef CONFIG_SPARSEMEM 439 VMCOREINFO_SYMBOL_ARRAY(mem_section); 440 VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS); 441 VMCOREINFO_STRUCT_SIZE(mem_section); 442 VMCOREINFO_OFFSET(mem_section, section_mem_map); 443 VMCOREINFO_NUMBER(SECTION_SIZE_BITS); 444 VMCOREINFO_NUMBER(MAX_PHYSMEM_BITS); 445 #endif 446 VMCOREINFO_STRUCT_SIZE(page); 447 VMCOREINFO_STRUCT_SIZE(pglist_data); 448 VMCOREINFO_STRUCT_SIZE(zone); 449 VMCOREINFO_STRUCT_SIZE(free_area); 450 VMCOREINFO_STRUCT_SIZE(list_head); 451 VMCOREINFO_SIZE(nodemask_t); 452 VMCOREINFO_OFFSET(page, flags); 453 VMCOREINFO_OFFSET(page, _refcount); 454 VMCOREINFO_OFFSET(page, mapping); 455 VMCOREINFO_OFFSET(page, lru); 456 VMCOREINFO_OFFSET(page, _mapcount); 457 VMCOREINFO_OFFSET(page, private); 458 VMCOREINFO_OFFSET(page, compound_dtor); 459 VMCOREINFO_OFFSET(page, compound_order); 460 VMCOREINFO_OFFSET(page, compound_head); 461 VMCOREINFO_OFFSET(pglist_data, node_zones); 462 VMCOREINFO_OFFSET(pglist_data, nr_zones); 463 #ifdef CONFIG_FLATMEM 464 VMCOREINFO_OFFSET(pglist_data, node_mem_map); 465 #endif 466 VMCOREINFO_OFFSET(pglist_data, node_start_pfn); 467 VMCOREINFO_OFFSET(pglist_data, node_spanned_pages); 468 VMCOREINFO_OFFSET(pglist_data, node_id); 469 VMCOREINFO_OFFSET(zone, free_area); 470 VMCOREINFO_OFFSET(zone, vm_stat); 471 VMCOREINFO_OFFSET(zone, spanned_pages); 472 VMCOREINFO_OFFSET(free_area, free_list); 473 VMCOREINFO_OFFSET(list_head, next); 474 VMCOREINFO_OFFSET(list_head, prev); 475 VMCOREINFO_OFFSET(vmap_area, va_start); 476 VMCOREINFO_OFFSET(vmap_area, list); 477 VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER); 478 log_buf_vmcoreinfo_setup(); 479 VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES); 480 VMCOREINFO_NUMBER(NR_FREE_PAGES); 481 VMCOREINFO_NUMBER(PG_lru); 482 VMCOREINFO_NUMBER(PG_private); 483 VMCOREINFO_NUMBER(PG_swapcache); 484 VMCOREINFO_NUMBER(PG_swapbacked); 485 VMCOREINFO_NUMBER(PG_slab); 486 #ifdef CONFIG_MEMORY_FAILURE 487 VMCOREINFO_NUMBER(PG_hwpoison); 488 #endif 489 VMCOREINFO_NUMBER(PG_head_mask); 490 #define PAGE_BUDDY_MAPCOUNT_VALUE (~PG_buddy) 491 VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE); 492 #ifdef CONFIG_HUGETLB_PAGE 493 VMCOREINFO_NUMBER(HUGETLB_PAGE_DTOR); 494 #define PAGE_OFFLINE_MAPCOUNT_VALUE (~PG_offline) 495 VMCOREINFO_NUMBER(PAGE_OFFLINE_MAPCOUNT_VALUE); 496 #endif 497 498 #ifdef CONFIG_KALLSYMS 499 VMCOREINFO_SYMBOL(kallsyms_names); 500 VMCOREINFO_SYMBOL(kallsyms_num_syms); 501 VMCOREINFO_SYMBOL(kallsyms_token_table); 502 VMCOREINFO_SYMBOL(kallsyms_token_index); 503 #ifdef CONFIG_KALLSYMS_BASE_RELATIVE 504 VMCOREINFO_SYMBOL(kallsyms_offsets); 505 VMCOREINFO_SYMBOL(kallsyms_relative_base); 506 #else 507 VMCOREINFO_SYMBOL(kallsyms_addresses); 508 #endif /* CONFIG_KALLSYMS_BASE_RELATIVE */ 509 #endif /* CONFIG_KALLSYMS */ 510 511 arch_crash_save_vmcoreinfo(); 512 update_vmcoreinfo_note(); 513 514 return 0; 515 } 516 517 subsys_initcall(crash_save_vmcoreinfo_init); 518