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