1 /* 2 * Firmware Assisted dump: A robust mechanism to get reliable kernel crash 3 * dump with assistance from firmware. This approach does not use kexec, 4 * instead firmware assists in booting the kdump kernel while preserving 5 * memory contents. The most of the code implementation has been adapted 6 * from phyp assisted dump implementation written by Linas Vepstas and 7 * Manish Ahuja 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 22 * 23 * Copyright 2011 IBM Corporation 24 * Author: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> 25 */ 26 27 #undef DEBUG 28 #define pr_fmt(fmt) "fadump: " fmt 29 30 #include <linux/string.h> 31 #include <linux/memblock.h> 32 #include <linux/delay.h> 33 #include <linux/debugfs.h> 34 #include <linux/seq_file.h> 35 #include <linux/crash_dump.h> 36 #include <linux/kobject.h> 37 #include <linux/sysfs.h> 38 39 #include <asm/page.h> 40 #include <asm/prom.h> 41 #include <asm/rtas.h> 42 #include <asm/fadump.h> 43 #include <asm/debug.h> 44 #include <asm/setup.h> 45 46 static struct fw_dump fw_dump; 47 static struct fadump_mem_struct fdm; 48 static const struct fadump_mem_struct *fdm_active; 49 50 static DEFINE_MUTEX(fadump_mutex); 51 struct fad_crash_memory_ranges crash_memory_ranges[INIT_CRASHMEM_RANGES]; 52 int crash_mem_ranges; 53 54 /* Scan the Firmware Assisted dump configuration details. */ 55 int __init early_init_dt_scan_fw_dump(unsigned long node, 56 const char *uname, int depth, void *data) 57 { 58 const __be32 *sections; 59 int i, num_sections; 60 int size; 61 const __be32 *token; 62 63 if (depth != 1 || strcmp(uname, "rtas") != 0) 64 return 0; 65 66 /* 67 * Check if Firmware Assisted dump is supported. if yes, check 68 * if dump has been initiated on last reboot. 69 */ 70 token = of_get_flat_dt_prop(node, "ibm,configure-kernel-dump", NULL); 71 if (!token) 72 return 1; 73 74 fw_dump.fadump_supported = 1; 75 fw_dump.ibm_configure_kernel_dump = be32_to_cpu(*token); 76 77 /* 78 * The 'ibm,kernel-dump' rtas node is present only if there is 79 * dump data waiting for us. 80 */ 81 fdm_active = of_get_flat_dt_prop(node, "ibm,kernel-dump", NULL); 82 if (fdm_active) 83 fw_dump.dump_active = 1; 84 85 /* Get the sizes required to store dump data for the firmware provided 86 * dump sections. 87 * For each dump section type supported, a 32bit cell which defines 88 * the ID of a supported section followed by two 32 bit cells which 89 * gives teh size of the section in bytes. 90 */ 91 sections = of_get_flat_dt_prop(node, "ibm,configure-kernel-dump-sizes", 92 &size); 93 94 if (!sections) 95 return 1; 96 97 num_sections = size / (3 * sizeof(u32)); 98 99 for (i = 0; i < num_sections; i++, sections += 3) { 100 u32 type = (u32)of_read_number(sections, 1); 101 102 switch (type) { 103 case FADUMP_CPU_STATE_DATA: 104 fw_dump.cpu_state_data_size = 105 of_read_ulong(§ions[1], 2); 106 break; 107 case FADUMP_HPTE_REGION: 108 fw_dump.hpte_region_size = 109 of_read_ulong(§ions[1], 2); 110 break; 111 } 112 } 113 114 return 1; 115 } 116 117 int is_fadump_active(void) 118 { 119 return fw_dump.dump_active; 120 } 121 122 /* Print firmware assisted dump configurations for debugging purpose. */ 123 static void fadump_show_config(void) 124 { 125 pr_debug("Support for firmware-assisted dump (fadump): %s\n", 126 (fw_dump.fadump_supported ? "present" : "no support")); 127 128 if (!fw_dump.fadump_supported) 129 return; 130 131 pr_debug("Fadump enabled : %s\n", 132 (fw_dump.fadump_enabled ? "yes" : "no")); 133 pr_debug("Dump Active : %s\n", 134 (fw_dump.dump_active ? "yes" : "no")); 135 pr_debug("Dump section sizes:\n"); 136 pr_debug(" CPU state data size: %lx\n", fw_dump.cpu_state_data_size); 137 pr_debug(" HPTE region size : %lx\n", fw_dump.hpte_region_size); 138 pr_debug("Boot memory size : %lx\n", fw_dump.boot_memory_size); 139 } 140 141 static unsigned long init_fadump_mem_struct(struct fadump_mem_struct *fdm, 142 unsigned long addr) 143 { 144 if (!fdm) 145 return 0; 146 147 memset(fdm, 0, sizeof(struct fadump_mem_struct)); 148 addr = addr & PAGE_MASK; 149 150 fdm->header.dump_format_version = cpu_to_be32(0x00000001); 151 fdm->header.dump_num_sections = cpu_to_be16(3); 152 fdm->header.dump_status_flag = 0; 153 fdm->header.offset_first_dump_section = 154 cpu_to_be32((u32)offsetof(struct fadump_mem_struct, cpu_state_data)); 155 156 /* 157 * Fields for disk dump option. 158 * We are not using disk dump option, hence set these fields to 0. 159 */ 160 fdm->header.dd_block_size = 0; 161 fdm->header.dd_block_offset = 0; 162 fdm->header.dd_num_blocks = 0; 163 fdm->header.dd_offset_disk_path = 0; 164 165 /* set 0 to disable an automatic dump-reboot. */ 166 fdm->header.max_time_auto = 0; 167 168 /* Kernel dump sections */ 169 /* cpu state data section. */ 170 fdm->cpu_state_data.request_flag = cpu_to_be32(FADUMP_REQUEST_FLAG); 171 fdm->cpu_state_data.source_data_type = cpu_to_be16(FADUMP_CPU_STATE_DATA); 172 fdm->cpu_state_data.source_address = 0; 173 fdm->cpu_state_data.source_len = cpu_to_be64(fw_dump.cpu_state_data_size); 174 fdm->cpu_state_data.destination_address = cpu_to_be64(addr); 175 addr += fw_dump.cpu_state_data_size; 176 177 /* hpte region section */ 178 fdm->hpte_region.request_flag = cpu_to_be32(FADUMP_REQUEST_FLAG); 179 fdm->hpte_region.source_data_type = cpu_to_be16(FADUMP_HPTE_REGION); 180 fdm->hpte_region.source_address = 0; 181 fdm->hpte_region.source_len = cpu_to_be64(fw_dump.hpte_region_size); 182 fdm->hpte_region.destination_address = cpu_to_be64(addr); 183 addr += fw_dump.hpte_region_size; 184 185 /* RMA region section */ 186 fdm->rmr_region.request_flag = cpu_to_be32(FADUMP_REQUEST_FLAG); 187 fdm->rmr_region.source_data_type = cpu_to_be16(FADUMP_REAL_MODE_REGION); 188 fdm->rmr_region.source_address = cpu_to_be64(RMA_START); 189 fdm->rmr_region.source_len = cpu_to_be64(fw_dump.boot_memory_size); 190 fdm->rmr_region.destination_address = cpu_to_be64(addr); 191 addr += fw_dump.boot_memory_size; 192 193 return addr; 194 } 195 196 /** 197 * fadump_calculate_reserve_size(): reserve variable boot area 5% of System RAM 198 * 199 * Function to find the largest memory size we need to reserve during early 200 * boot process. This will be the size of the memory that is required for a 201 * kernel to boot successfully. 202 * 203 * This function has been taken from phyp-assisted dump feature implementation. 204 * 205 * returns larger of 256MB or 5% rounded down to multiples of 256MB. 206 * 207 * TODO: Come up with better approach to find out more accurate memory size 208 * that is required for a kernel to boot successfully. 209 * 210 */ 211 static inline unsigned long fadump_calculate_reserve_size(void) 212 { 213 unsigned long size; 214 215 /* 216 * Check if the size is specified through fadump_reserve_mem= cmdline 217 * option. If yes, then use that. 218 */ 219 if (fw_dump.reserve_bootvar) 220 return fw_dump.reserve_bootvar; 221 222 /* divide by 20 to get 5% of value */ 223 size = memblock_end_of_DRAM() / 20; 224 225 /* round it down in multiples of 256 */ 226 size = size & ~0x0FFFFFFFUL; 227 228 /* Truncate to memory_limit. We don't want to over reserve the memory.*/ 229 if (memory_limit && size > memory_limit) 230 size = memory_limit; 231 232 return (size > MIN_BOOT_MEM ? size : MIN_BOOT_MEM); 233 } 234 235 /* 236 * Calculate the total memory size required to be reserved for 237 * firmware-assisted dump registration. 238 */ 239 static unsigned long get_fadump_area_size(void) 240 { 241 unsigned long size = 0; 242 243 size += fw_dump.cpu_state_data_size; 244 size += fw_dump.hpte_region_size; 245 size += fw_dump.boot_memory_size; 246 size += sizeof(struct fadump_crash_info_header); 247 size += sizeof(struct elfhdr); /* ELF core header.*/ 248 size += sizeof(struct elf_phdr); /* place holder for cpu notes */ 249 /* Program headers for crash memory regions. */ 250 size += sizeof(struct elf_phdr) * (memblock_num_regions(memory) + 2); 251 252 size = PAGE_ALIGN(size); 253 return size; 254 } 255 256 int __init fadump_reserve_mem(void) 257 { 258 unsigned long base, size, memory_boundary; 259 260 if (!fw_dump.fadump_enabled) 261 return 0; 262 263 if (!fw_dump.fadump_supported) { 264 printk(KERN_INFO "Firmware-assisted dump is not supported on" 265 " this hardware\n"); 266 fw_dump.fadump_enabled = 0; 267 return 0; 268 } 269 /* 270 * Initialize boot memory size 271 * If dump is active then we have already calculated the size during 272 * first kernel. 273 */ 274 if (fdm_active) 275 fw_dump.boot_memory_size = be64_to_cpu(fdm_active->rmr_region.source_len); 276 else 277 fw_dump.boot_memory_size = fadump_calculate_reserve_size(); 278 279 /* 280 * Calculate the memory boundary. 281 * If memory_limit is less than actual memory boundary then reserve 282 * the memory for fadump beyond the memory_limit and adjust the 283 * memory_limit accordingly, so that the running kernel can run with 284 * specified memory_limit. 285 */ 286 if (memory_limit && memory_limit < memblock_end_of_DRAM()) { 287 size = get_fadump_area_size(); 288 if ((memory_limit + size) < memblock_end_of_DRAM()) 289 memory_limit += size; 290 else 291 memory_limit = memblock_end_of_DRAM(); 292 printk(KERN_INFO "Adjusted memory_limit for firmware-assisted" 293 " dump, now %#016llx\n", memory_limit); 294 } 295 if (memory_limit) 296 memory_boundary = memory_limit; 297 else 298 memory_boundary = memblock_end_of_DRAM(); 299 300 if (fw_dump.dump_active) { 301 printk(KERN_INFO "Firmware-assisted dump is active.\n"); 302 /* 303 * If last boot has crashed then reserve all the memory 304 * above boot_memory_size so that we don't touch it until 305 * dump is written to disk by userspace tool. This memory 306 * will be released for general use once the dump is saved. 307 */ 308 base = fw_dump.boot_memory_size; 309 size = memory_boundary - base; 310 memblock_reserve(base, size); 311 printk(KERN_INFO "Reserved %ldMB of memory at %ldMB " 312 "for saving crash dump\n", 313 (unsigned long)(size >> 20), 314 (unsigned long)(base >> 20)); 315 316 fw_dump.fadumphdr_addr = 317 be64_to_cpu(fdm_active->rmr_region.destination_address) + 318 be64_to_cpu(fdm_active->rmr_region.source_len); 319 pr_debug("fadumphdr_addr = %p\n", 320 (void *) fw_dump.fadumphdr_addr); 321 } else { 322 /* Reserve the memory at the top of memory. */ 323 size = get_fadump_area_size(); 324 base = memory_boundary - size; 325 memblock_reserve(base, size); 326 printk(KERN_INFO "Reserved %ldMB of memory at %ldMB " 327 "for firmware-assisted dump\n", 328 (unsigned long)(size >> 20), 329 (unsigned long)(base >> 20)); 330 } 331 fw_dump.reserve_dump_area_start = base; 332 fw_dump.reserve_dump_area_size = size; 333 return 1; 334 } 335 336 unsigned long __init arch_reserved_kernel_pages(void) 337 { 338 return memblock_reserved_size() / PAGE_SIZE; 339 } 340 341 /* Look for fadump= cmdline option. */ 342 static int __init early_fadump_param(char *p) 343 { 344 if (!p) 345 return 1; 346 347 if (strncmp(p, "on", 2) == 0) 348 fw_dump.fadump_enabled = 1; 349 else if (strncmp(p, "off", 3) == 0) 350 fw_dump.fadump_enabled = 0; 351 352 return 0; 353 } 354 early_param("fadump", early_fadump_param); 355 356 /* Look for fadump_reserve_mem= cmdline option */ 357 static int __init early_fadump_reserve_mem(char *p) 358 { 359 if (p) 360 fw_dump.reserve_bootvar = memparse(p, &p); 361 return 0; 362 } 363 early_param("fadump_reserve_mem", early_fadump_reserve_mem); 364 365 static void register_fw_dump(struct fadump_mem_struct *fdm) 366 { 367 int rc; 368 unsigned int wait_time; 369 370 pr_debug("Registering for firmware-assisted kernel dump...\n"); 371 372 /* TODO: Add upper time limit for the delay */ 373 do { 374 rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL, 375 FADUMP_REGISTER, fdm, 376 sizeof(struct fadump_mem_struct)); 377 378 wait_time = rtas_busy_delay_time(rc); 379 if (wait_time) 380 mdelay(wait_time); 381 382 } while (wait_time); 383 384 switch (rc) { 385 case -1: 386 printk(KERN_ERR "Failed to register firmware-assisted kernel" 387 " dump. Hardware Error(%d).\n", rc); 388 break; 389 case -3: 390 printk(KERN_ERR "Failed to register firmware-assisted kernel" 391 " dump. Parameter Error(%d).\n", rc); 392 break; 393 case -9: 394 printk(KERN_ERR "firmware-assisted kernel dump is already " 395 " registered."); 396 fw_dump.dump_registered = 1; 397 break; 398 case 0: 399 printk(KERN_INFO "firmware-assisted kernel dump registration" 400 " is successful\n"); 401 fw_dump.dump_registered = 1; 402 break; 403 } 404 } 405 406 void crash_fadump(struct pt_regs *regs, const char *str) 407 { 408 struct fadump_crash_info_header *fdh = NULL; 409 410 if (!fw_dump.dump_registered || !fw_dump.fadumphdr_addr) 411 return; 412 413 fdh = __va(fw_dump.fadumphdr_addr); 414 crashing_cpu = smp_processor_id(); 415 fdh->crashing_cpu = crashing_cpu; 416 crash_save_vmcoreinfo(); 417 418 if (regs) 419 fdh->regs = *regs; 420 else 421 ppc_save_regs(&fdh->regs); 422 423 fdh->online_mask = *cpu_online_mask; 424 425 /* Call ibm,os-term rtas call to trigger firmware assisted dump */ 426 rtas_os_term((char *)str); 427 } 428 429 #define GPR_MASK 0xffffff0000000000 430 static inline int fadump_gpr_index(u64 id) 431 { 432 int i = -1; 433 char str[3]; 434 435 if ((id & GPR_MASK) == REG_ID("GPR")) { 436 /* get the digits at the end */ 437 id &= ~GPR_MASK; 438 id >>= 24; 439 str[2] = '\0'; 440 str[1] = id & 0xff; 441 str[0] = (id >> 8) & 0xff; 442 sscanf(str, "%d", &i); 443 if (i > 31) 444 i = -1; 445 } 446 return i; 447 } 448 449 static inline void fadump_set_regval(struct pt_regs *regs, u64 reg_id, 450 u64 reg_val) 451 { 452 int i; 453 454 i = fadump_gpr_index(reg_id); 455 if (i >= 0) 456 regs->gpr[i] = (unsigned long)reg_val; 457 else if (reg_id == REG_ID("NIA")) 458 regs->nip = (unsigned long)reg_val; 459 else if (reg_id == REG_ID("MSR")) 460 regs->msr = (unsigned long)reg_val; 461 else if (reg_id == REG_ID("CTR")) 462 regs->ctr = (unsigned long)reg_val; 463 else if (reg_id == REG_ID("LR")) 464 regs->link = (unsigned long)reg_val; 465 else if (reg_id == REG_ID("XER")) 466 regs->xer = (unsigned long)reg_val; 467 else if (reg_id == REG_ID("CR")) 468 regs->ccr = (unsigned long)reg_val; 469 else if (reg_id == REG_ID("DAR")) 470 regs->dar = (unsigned long)reg_val; 471 else if (reg_id == REG_ID("DSISR")) 472 regs->dsisr = (unsigned long)reg_val; 473 } 474 475 static struct fadump_reg_entry* 476 fadump_read_registers(struct fadump_reg_entry *reg_entry, struct pt_regs *regs) 477 { 478 memset(regs, 0, sizeof(struct pt_regs)); 479 480 while (be64_to_cpu(reg_entry->reg_id) != REG_ID("CPUEND")) { 481 fadump_set_regval(regs, be64_to_cpu(reg_entry->reg_id), 482 be64_to_cpu(reg_entry->reg_value)); 483 reg_entry++; 484 } 485 reg_entry++; 486 return reg_entry; 487 } 488 489 static u32 *fadump_append_elf_note(u32 *buf, char *name, unsigned type, 490 void *data, size_t data_len) 491 { 492 struct elf_note note; 493 494 note.n_namesz = strlen(name) + 1; 495 note.n_descsz = data_len; 496 note.n_type = type; 497 memcpy(buf, ¬e, sizeof(note)); 498 buf += (sizeof(note) + 3)/4; 499 memcpy(buf, name, note.n_namesz); 500 buf += (note.n_namesz + 3)/4; 501 memcpy(buf, data, note.n_descsz); 502 buf += (note.n_descsz + 3)/4; 503 504 return buf; 505 } 506 507 static void fadump_final_note(u32 *buf) 508 { 509 struct elf_note note; 510 511 note.n_namesz = 0; 512 note.n_descsz = 0; 513 note.n_type = 0; 514 memcpy(buf, ¬e, sizeof(note)); 515 } 516 517 static u32 *fadump_regs_to_elf_notes(u32 *buf, struct pt_regs *regs) 518 { 519 struct elf_prstatus prstatus; 520 521 memset(&prstatus, 0, sizeof(prstatus)); 522 /* 523 * FIXME: How do i get PID? Do I really need it? 524 * prstatus.pr_pid = ???? 525 */ 526 elf_core_copy_kernel_regs(&prstatus.pr_reg, regs); 527 buf = fadump_append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS, 528 &prstatus, sizeof(prstatus)); 529 return buf; 530 } 531 532 static void fadump_update_elfcore_header(char *bufp) 533 { 534 struct elfhdr *elf; 535 struct elf_phdr *phdr; 536 537 elf = (struct elfhdr *)bufp; 538 bufp += sizeof(struct elfhdr); 539 540 /* First note is a place holder for cpu notes info. */ 541 phdr = (struct elf_phdr *)bufp; 542 543 if (phdr->p_type == PT_NOTE) { 544 phdr->p_paddr = fw_dump.cpu_notes_buf; 545 phdr->p_offset = phdr->p_paddr; 546 phdr->p_filesz = fw_dump.cpu_notes_buf_size; 547 phdr->p_memsz = fw_dump.cpu_notes_buf_size; 548 } 549 return; 550 } 551 552 static void *fadump_cpu_notes_buf_alloc(unsigned long size) 553 { 554 void *vaddr; 555 struct page *page; 556 unsigned long order, count, i; 557 558 order = get_order(size); 559 vaddr = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, order); 560 if (!vaddr) 561 return NULL; 562 563 count = 1 << order; 564 page = virt_to_page(vaddr); 565 for (i = 0; i < count; i++) 566 SetPageReserved(page + i); 567 return vaddr; 568 } 569 570 static void fadump_cpu_notes_buf_free(unsigned long vaddr, unsigned long size) 571 { 572 struct page *page; 573 unsigned long order, count, i; 574 575 order = get_order(size); 576 count = 1 << order; 577 page = virt_to_page(vaddr); 578 for (i = 0; i < count; i++) 579 ClearPageReserved(page + i); 580 __free_pages(page, order); 581 } 582 583 /* 584 * Read CPU state dump data and convert it into ELF notes. 585 * The CPU dump starts with magic number "REGSAVE". NumCpusOffset should be 586 * used to access the data to allow for additional fields to be added without 587 * affecting compatibility. Each list of registers for a CPU starts with 588 * "CPUSTRT" and ends with "CPUEND". Each register entry is of 16 bytes, 589 * 8 Byte ASCII identifier and 8 Byte register value. The register entry 590 * with identifier "CPUSTRT" and "CPUEND" contains 4 byte cpu id as part 591 * of register value. For more details refer to PAPR document. 592 * 593 * Only for the crashing cpu we ignore the CPU dump data and get exact 594 * state from fadump crash info structure populated by first kernel at the 595 * time of crash. 596 */ 597 static int __init fadump_build_cpu_notes(const struct fadump_mem_struct *fdm) 598 { 599 struct fadump_reg_save_area_header *reg_header; 600 struct fadump_reg_entry *reg_entry; 601 struct fadump_crash_info_header *fdh = NULL; 602 void *vaddr; 603 unsigned long addr; 604 u32 num_cpus, *note_buf; 605 struct pt_regs regs; 606 int i, rc = 0, cpu = 0; 607 608 if (!fdm->cpu_state_data.bytes_dumped) 609 return -EINVAL; 610 611 addr = be64_to_cpu(fdm->cpu_state_data.destination_address); 612 vaddr = __va(addr); 613 614 reg_header = vaddr; 615 if (be64_to_cpu(reg_header->magic_number) != REGSAVE_AREA_MAGIC) { 616 printk(KERN_ERR "Unable to read register save area.\n"); 617 return -ENOENT; 618 } 619 pr_debug("--------CPU State Data------------\n"); 620 pr_debug("Magic Number: %llx\n", be64_to_cpu(reg_header->magic_number)); 621 pr_debug("NumCpuOffset: %x\n", be32_to_cpu(reg_header->num_cpu_offset)); 622 623 vaddr += be32_to_cpu(reg_header->num_cpu_offset); 624 num_cpus = be32_to_cpu(*((__be32 *)(vaddr))); 625 pr_debug("NumCpus : %u\n", num_cpus); 626 vaddr += sizeof(u32); 627 reg_entry = (struct fadump_reg_entry *)vaddr; 628 629 /* Allocate buffer to hold cpu crash notes. */ 630 fw_dump.cpu_notes_buf_size = num_cpus * sizeof(note_buf_t); 631 fw_dump.cpu_notes_buf_size = PAGE_ALIGN(fw_dump.cpu_notes_buf_size); 632 note_buf = fadump_cpu_notes_buf_alloc(fw_dump.cpu_notes_buf_size); 633 if (!note_buf) { 634 printk(KERN_ERR "Failed to allocate 0x%lx bytes for " 635 "cpu notes buffer\n", fw_dump.cpu_notes_buf_size); 636 return -ENOMEM; 637 } 638 fw_dump.cpu_notes_buf = __pa(note_buf); 639 640 pr_debug("Allocated buffer for cpu notes of size %ld at %p\n", 641 (num_cpus * sizeof(note_buf_t)), note_buf); 642 643 if (fw_dump.fadumphdr_addr) 644 fdh = __va(fw_dump.fadumphdr_addr); 645 646 for (i = 0; i < num_cpus; i++) { 647 if (be64_to_cpu(reg_entry->reg_id) != REG_ID("CPUSTRT")) { 648 printk(KERN_ERR "Unable to read CPU state data\n"); 649 rc = -ENOENT; 650 goto error_out; 651 } 652 /* Lower 4 bytes of reg_value contains logical cpu id */ 653 cpu = be64_to_cpu(reg_entry->reg_value) & FADUMP_CPU_ID_MASK; 654 if (fdh && !cpumask_test_cpu(cpu, &fdh->online_mask)) { 655 SKIP_TO_NEXT_CPU(reg_entry); 656 continue; 657 } 658 pr_debug("Reading register data for cpu %d...\n", cpu); 659 if (fdh && fdh->crashing_cpu == cpu) { 660 regs = fdh->regs; 661 note_buf = fadump_regs_to_elf_notes(note_buf, ®s); 662 SKIP_TO_NEXT_CPU(reg_entry); 663 } else { 664 reg_entry++; 665 reg_entry = fadump_read_registers(reg_entry, ®s); 666 note_buf = fadump_regs_to_elf_notes(note_buf, ®s); 667 } 668 } 669 fadump_final_note(note_buf); 670 671 if (fdh) { 672 pr_debug("Updating elfcore header (%llx) with cpu notes\n", 673 fdh->elfcorehdr_addr); 674 fadump_update_elfcore_header((char *)__va(fdh->elfcorehdr_addr)); 675 } 676 return 0; 677 678 error_out: 679 fadump_cpu_notes_buf_free((unsigned long)__va(fw_dump.cpu_notes_buf), 680 fw_dump.cpu_notes_buf_size); 681 fw_dump.cpu_notes_buf = 0; 682 fw_dump.cpu_notes_buf_size = 0; 683 return rc; 684 685 } 686 687 /* 688 * Validate and process the dump data stored by firmware before exporting 689 * it through '/proc/vmcore'. 690 */ 691 static int __init process_fadump(const struct fadump_mem_struct *fdm_active) 692 { 693 struct fadump_crash_info_header *fdh; 694 int rc = 0; 695 696 if (!fdm_active || !fw_dump.fadumphdr_addr) 697 return -EINVAL; 698 699 /* Check if the dump data is valid. */ 700 if ((be16_to_cpu(fdm_active->header.dump_status_flag) == FADUMP_ERROR_FLAG) || 701 (fdm_active->cpu_state_data.error_flags != 0) || 702 (fdm_active->rmr_region.error_flags != 0)) { 703 printk(KERN_ERR "Dump taken by platform is not valid\n"); 704 return -EINVAL; 705 } 706 if ((fdm_active->rmr_region.bytes_dumped != 707 fdm_active->rmr_region.source_len) || 708 !fdm_active->cpu_state_data.bytes_dumped) { 709 printk(KERN_ERR "Dump taken by platform is incomplete\n"); 710 return -EINVAL; 711 } 712 713 /* Validate the fadump crash info header */ 714 fdh = __va(fw_dump.fadumphdr_addr); 715 if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) { 716 printk(KERN_ERR "Crash info header is not valid.\n"); 717 return -EINVAL; 718 } 719 720 rc = fadump_build_cpu_notes(fdm_active); 721 if (rc) 722 return rc; 723 724 /* 725 * We are done validating dump info and elfcore header is now ready 726 * to be exported. set elfcorehdr_addr so that vmcore module will 727 * export the elfcore header through '/proc/vmcore'. 728 */ 729 elfcorehdr_addr = fdh->elfcorehdr_addr; 730 731 return 0; 732 } 733 734 static inline void fadump_add_crash_memory(unsigned long long base, 735 unsigned long long end) 736 { 737 if (base == end) 738 return; 739 740 pr_debug("crash_memory_range[%d] [%#016llx-%#016llx], %#llx bytes\n", 741 crash_mem_ranges, base, end - 1, (end - base)); 742 crash_memory_ranges[crash_mem_ranges].base = base; 743 crash_memory_ranges[crash_mem_ranges].size = end - base; 744 crash_mem_ranges++; 745 } 746 747 static void fadump_exclude_reserved_area(unsigned long long start, 748 unsigned long long end) 749 { 750 unsigned long long ra_start, ra_end; 751 752 ra_start = fw_dump.reserve_dump_area_start; 753 ra_end = ra_start + fw_dump.reserve_dump_area_size; 754 755 if ((ra_start < end) && (ra_end > start)) { 756 if ((start < ra_start) && (end > ra_end)) { 757 fadump_add_crash_memory(start, ra_start); 758 fadump_add_crash_memory(ra_end, end); 759 } else if (start < ra_start) { 760 fadump_add_crash_memory(start, ra_start); 761 } else if (ra_end < end) { 762 fadump_add_crash_memory(ra_end, end); 763 } 764 } else 765 fadump_add_crash_memory(start, end); 766 } 767 768 static int fadump_init_elfcore_header(char *bufp) 769 { 770 struct elfhdr *elf; 771 772 elf = (struct elfhdr *) bufp; 773 bufp += sizeof(struct elfhdr); 774 memcpy(elf->e_ident, ELFMAG, SELFMAG); 775 elf->e_ident[EI_CLASS] = ELF_CLASS; 776 elf->e_ident[EI_DATA] = ELF_DATA; 777 elf->e_ident[EI_VERSION] = EV_CURRENT; 778 elf->e_ident[EI_OSABI] = ELF_OSABI; 779 memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD); 780 elf->e_type = ET_CORE; 781 elf->e_machine = ELF_ARCH; 782 elf->e_version = EV_CURRENT; 783 elf->e_entry = 0; 784 elf->e_phoff = sizeof(struct elfhdr); 785 elf->e_shoff = 0; 786 #if defined(_CALL_ELF) 787 elf->e_flags = _CALL_ELF; 788 #else 789 elf->e_flags = 0; 790 #endif 791 elf->e_ehsize = sizeof(struct elfhdr); 792 elf->e_phentsize = sizeof(struct elf_phdr); 793 elf->e_phnum = 0; 794 elf->e_shentsize = 0; 795 elf->e_shnum = 0; 796 elf->e_shstrndx = 0; 797 798 return 0; 799 } 800 801 /* 802 * Traverse through memblock structure and setup crash memory ranges. These 803 * ranges will be used create PT_LOAD program headers in elfcore header. 804 */ 805 static void fadump_setup_crash_memory_ranges(void) 806 { 807 struct memblock_region *reg; 808 unsigned long long start, end; 809 810 pr_debug("Setup crash memory ranges.\n"); 811 crash_mem_ranges = 0; 812 /* 813 * add the first memory chunk (RMA_START through boot_memory_size) as 814 * a separate memory chunk. The reason is, at the time crash firmware 815 * will move the content of this memory chunk to different location 816 * specified during fadump registration. We need to create a separate 817 * program header for this chunk with the correct offset. 818 */ 819 fadump_add_crash_memory(RMA_START, fw_dump.boot_memory_size); 820 821 for_each_memblock(memory, reg) { 822 start = (unsigned long long)reg->base; 823 end = start + (unsigned long long)reg->size; 824 if (start == RMA_START && end >= fw_dump.boot_memory_size) 825 start = fw_dump.boot_memory_size; 826 827 /* add this range excluding the reserved dump area. */ 828 fadump_exclude_reserved_area(start, end); 829 } 830 } 831 832 /* 833 * If the given physical address falls within the boot memory region then 834 * return the relocated address that points to the dump region reserved 835 * for saving initial boot memory contents. 836 */ 837 static inline unsigned long fadump_relocate(unsigned long paddr) 838 { 839 if (paddr > RMA_START && paddr < fw_dump.boot_memory_size) 840 return be64_to_cpu(fdm.rmr_region.destination_address) + paddr; 841 else 842 return paddr; 843 } 844 845 static int fadump_create_elfcore_headers(char *bufp) 846 { 847 struct elfhdr *elf; 848 struct elf_phdr *phdr; 849 int i; 850 851 fadump_init_elfcore_header(bufp); 852 elf = (struct elfhdr *)bufp; 853 bufp += sizeof(struct elfhdr); 854 855 /* 856 * setup ELF PT_NOTE, place holder for cpu notes info. The notes info 857 * will be populated during second kernel boot after crash. Hence 858 * this PT_NOTE will always be the first elf note. 859 * 860 * NOTE: Any new ELF note addition should be placed after this note. 861 */ 862 phdr = (struct elf_phdr *)bufp; 863 bufp += sizeof(struct elf_phdr); 864 phdr->p_type = PT_NOTE; 865 phdr->p_flags = 0; 866 phdr->p_vaddr = 0; 867 phdr->p_align = 0; 868 869 phdr->p_offset = 0; 870 phdr->p_paddr = 0; 871 phdr->p_filesz = 0; 872 phdr->p_memsz = 0; 873 874 (elf->e_phnum)++; 875 876 /* setup ELF PT_NOTE for vmcoreinfo */ 877 phdr = (struct elf_phdr *)bufp; 878 bufp += sizeof(struct elf_phdr); 879 phdr->p_type = PT_NOTE; 880 phdr->p_flags = 0; 881 phdr->p_vaddr = 0; 882 phdr->p_align = 0; 883 884 phdr->p_paddr = fadump_relocate(paddr_vmcoreinfo_note()); 885 phdr->p_offset = phdr->p_paddr; 886 phdr->p_memsz = vmcoreinfo_max_size; 887 phdr->p_filesz = vmcoreinfo_max_size; 888 889 /* Increment number of program headers. */ 890 (elf->e_phnum)++; 891 892 /* setup PT_LOAD sections. */ 893 894 for (i = 0; i < crash_mem_ranges; i++) { 895 unsigned long long mbase, msize; 896 mbase = crash_memory_ranges[i].base; 897 msize = crash_memory_ranges[i].size; 898 899 if (!msize) 900 continue; 901 902 phdr = (struct elf_phdr *)bufp; 903 bufp += sizeof(struct elf_phdr); 904 phdr->p_type = PT_LOAD; 905 phdr->p_flags = PF_R|PF_W|PF_X; 906 phdr->p_offset = mbase; 907 908 if (mbase == RMA_START) { 909 /* 910 * The entire RMA region will be moved by firmware 911 * to the specified destination_address. Hence set 912 * the correct offset. 913 */ 914 phdr->p_offset = be64_to_cpu(fdm.rmr_region.destination_address); 915 } 916 917 phdr->p_paddr = mbase; 918 phdr->p_vaddr = (unsigned long)__va(mbase); 919 phdr->p_filesz = msize; 920 phdr->p_memsz = msize; 921 phdr->p_align = 0; 922 923 /* Increment number of program headers. */ 924 (elf->e_phnum)++; 925 } 926 return 0; 927 } 928 929 static unsigned long init_fadump_header(unsigned long addr) 930 { 931 struct fadump_crash_info_header *fdh; 932 933 if (!addr) 934 return 0; 935 936 fw_dump.fadumphdr_addr = addr; 937 fdh = __va(addr); 938 addr += sizeof(struct fadump_crash_info_header); 939 940 memset(fdh, 0, sizeof(struct fadump_crash_info_header)); 941 fdh->magic_number = FADUMP_CRASH_INFO_MAGIC; 942 fdh->elfcorehdr_addr = addr; 943 /* We will set the crashing cpu id in crash_fadump() during crash. */ 944 fdh->crashing_cpu = CPU_UNKNOWN; 945 946 return addr; 947 } 948 949 static void register_fadump(void) 950 { 951 unsigned long addr; 952 void *vaddr; 953 954 /* 955 * If no memory is reserved then we can not register for firmware- 956 * assisted dump. 957 */ 958 if (!fw_dump.reserve_dump_area_size) 959 return; 960 961 fadump_setup_crash_memory_ranges(); 962 963 addr = be64_to_cpu(fdm.rmr_region.destination_address) + be64_to_cpu(fdm.rmr_region.source_len); 964 /* Initialize fadump crash info header. */ 965 addr = init_fadump_header(addr); 966 vaddr = __va(addr); 967 968 pr_debug("Creating ELF core headers at %#016lx\n", addr); 969 fadump_create_elfcore_headers(vaddr); 970 971 /* register the future kernel dump with firmware. */ 972 register_fw_dump(&fdm); 973 } 974 975 static int fadump_unregister_dump(struct fadump_mem_struct *fdm) 976 { 977 int rc = 0; 978 unsigned int wait_time; 979 980 pr_debug("Un-register firmware-assisted dump\n"); 981 982 /* TODO: Add upper time limit for the delay */ 983 do { 984 rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL, 985 FADUMP_UNREGISTER, fdm, 986 sizeof(struct fadump_mem_struct)); 987 988 wait_time = rtas_busy_delay_time(rc); 989 if (wait_time) 990 mdelay(wait_time); 991 } while (wait_time); 992 993 if (rc) { 994 printk(KERN_ERR "Failed to un-register firmware-assisted dump." 995 " unexpected error(%d).\n", rc); 996 return rc; 997 } 998 fw_dump.dump_registered = 0; 999 return 0; 1000 } 1001 1002 static int fadump_invalidate_dump(struct fadump_mem_struct *fdm) 1003 { 1004 int rc = 0; 1005 unsigned int wait_time; 1006 1007 pr_debug("Invalidating firmware-assisted dump registration\n"); 1008 1009 /* TODO: Add upper time limit for the delay */ 1010 do { 1011 rc = rtas_call(fw_dump.ibm_configure_kernel_dump, 3, 1, NULL, 1012 FADUMP_INVALIDATE, fdm, 1013 sizeof(struct fadump_mem_struct)); 1014 1015 wait_time = rtas_busy_delay_time(rc); 1016 if (wait_time) 1017 mdelay(wait_time); 1018 } while (wait_time); 1019 1020 if (rc) { 1021 pr_err("Failed to invalidate firmware-assisted dump registration. Unexpected error (%d).\n", rc); 1022 return rc; 1023 } 1024 fw_dump.dump_active = 0; 1025 fdm_active = NULL; 1026 return 0; 1027 } 1028 1029 void fadump_cleanup(void) 1030 { 1031 /* Invalidate the registration only if dump is active. */ 1032 if (fw_dump.dump_active) { 1033 init_fadump_mem_struct(&fdm, 1034 be64_to_cpu(fdm_active->cpu_state_data.destination_address)); 1035 fadump_invalidate_dump(&fdm); 1036 } 1037 } 1038 1039 /* 1040 * Release the memory that was reserved in early boot to preserve the memory 1041 * contents. The released memory will be available for general use. 1042 */ 1043 static void fadump_release_memory(unsigned long begin, unsigned long end) 1044 { 1045 unsigned long addr; 1046 unsigned long ra_start, ra_end; 1047 1048 ra_start = fw_dump.reserve_dump_area_start; 1049 ra_end = ra_start + fw_dump.reserve_dump_area_size; 1050 1051 for (addr = begin; addr < end; addr += PAGE_SIZE) { 1052 /* 1053 * exclude the dump reserve area. Will reuse it for next 1054 * fadump registration. 1055 */ 1056 if (addr <= ra_end && ((addr + PAGE_SIZE) > ra_start)) 1057 continue; 1058 1059 free_reserved_page(pfn_to_page(addr >> PAGE_SHIFT)); 1060 } 1061 } 1062 1063 static void fadump_invalidate_release_mem(void) 1064 { 1065 unsigned long reserved_area_start, reserved_area_end; 1066 unsigned long destination_address; 1067 1068 mutex_lock(&fadump_mutex); 1069 if (!fw_dump.dump_active) { 1070 mutex_unlock(&fadump_mutex); 1071 return; 1072 } 1073 1074 destination_address = be64_to_cpu(fdm_active->cpu_state_data.destination_address); 1075 fadump_cleanup(); 1076 mutex_unlock(&fadump_mutex); 1077 1078 /* 1079 * Save the current reserved memory bounds we will require them 1080 * later for releasing the memory for general use. 1081 */ 1082 reserved_area_start = fw_dump.reserve_dump_area_start; 1083 reserved_area_end = reserved_area_start + 1084 fw_dump.reserve_dump_area_size; 1085 /* 1086 * Setup reserve_dump_area_start and its size so that we can 1087 * reuse this reserved memory for Re-registration. 1088 */ 1089 fw_dump.reserve_dump_area_start = destination_address; 1090 fw_dump.reserve_dump_area_size = get_fadump_area_size(); 1091 1092 fadump_release_memory(reserved_area_start, reserved_area_end); 1093 if (fw_dump.cpu_notes_buf) { 1094 fadump_cpu_notes_buf_free( 1095 (unsigned long)__va(fw_dump.cpu_notes_buf), 1096 fw_dump.cpu_notes_buf_size); 1097 fw_dump.cpu_notes_buf = 0; 1098 fw_dump.cpu_notes_buf_size = 0; 1099 } 1100 /* Initialize the kernel dump memory structure for FAD registration. */ 1101 init_fadump_mem_struct(&fdm, fw_dump.reserve_dump_area_start); 1102 } 1103 1104 static ssize_t fadump_release_memory_store(struct kobject *kobj, 1105 struct kobj_attribute *attr, 1106 const char *buf, size_t count) 1107 { 1108 if (!fw_dump.dump_active) 1109 return -EPERM; 1110 1111 if (buf[0] == '1') { 1112 /* 1113 * Take away the '/proc/vmcore'. We are releasing the dump 1114 * memory, hence it will not be valid anymore. 1115 */ 1116 #ifdef CONFIG_PROC_VMCORE 1117 vmcore_cleanup(); 1118 #endif 1119 fadump_invalidate_release_mem(); 1120 1121 } else 1122 return -EINVAL; 1123 return count; 1124 } 1125 1126 static ssize_t fadump_enabled_show(struct kobject *kobj, 1127 struct kobj_attribute *attr, 1128 char *buf) 1129 { 1130 return sprintf(buf, "%d\n", fw_dump.fadump_enabled); 1131 } 1132 1133 static ssize_t fadump_register_show(struct kobject *kobj, 1134 struct kobj_attribute *attr, 1135 char *buf) 1136 { 1137 return sprintf(buf, "%d\n", fw_dump.dump_registered); 1138 } 1139 1140 static ssize_t fadump_register_store(struct kobject *kobj, 1141 struct kobj_attribute *attr, 1142 const char *buf, size_t count) 1143 { 1144 int ret = 0; 1145 1146 if (!fw_dump.fadump_enabled || fdm_active) 1147 return -EPERM; 1148 1149 mutex_lock(&fadump_mutex); 1150 1151 switch (buf[0]) { 1152 case '0': 1153 if (fw_dump.dump_registered == 0) { 1154 ret = -EINVAL; 1155 goto unlock_out; 1156 } 1157 /* Un-register Firmware-assisted dump */ 1158 fadump_unregister_dump(&fdm); 1159 break; 1160 case '1': 1161 if (fw_dump.dump_registered == 1) { 1162 ret = -EINVAL; 1163 goto unlock_out; 1164 } 1165 /* Register Firmware-assisted dump */ 1166 register_fadump(); 1167 break; 1168 default: 1169 ret = -EINVAL; 1170 break; 1171 } 1172 1173 unlock_out: 1174 mutex_unlock(&fadump_mutex); 1175 return ret < 0 ? ret : count; 1176 } 1177 1178 static int fadump_region_show(struct seq_file *m, void *private) 1179 { 1180 const struct fadump_mem_struct *fdm_ptr; 1181 1182 if (!fw_dump.fadump_enabled) 1183 return 0; 1184 1185 mutex_lock(&fadump_mutex); 1186 if (fdm_active) 1187 fdm_ptr = fdm_active; 1188 else { 1189 mutex_unlock(&fadump_mutex); 1190 fdm_ptr = &fdm; 1191 } 1192 1193 seq_printf(m, 1194 "CPU : [%#016llx-%#016llx] %#llx bytes, " 1195 "Dumped: %#llx\n", 1196 be64_to_cpu(fdm_ptr->cpu_state_data.destination_address), 1197 be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) + 1198 be64_to_cpu(fdm_ptr->cpu_state_data.source_len) - 1, 1199 be64_to_cpu(fdm_ptr->cpu_state_data.source_len), 1200 be64_to_cpu(fdm_ptr->cpu_state_data.bytes_dumped)); 1201 seq_printf(m, 1202 "HPTE: [%#016llx-%#016llx] %#llx bytes, " 1203 "Dumped: %#llx\n", 1204 be64_to_cpu(fdm_ptr->hpte_region.destination_address), 1205 be64_to_cpu(fdm_ptr->hpte_region.destination_address) + 1206 be64_to_cpu(fdm_ptr->hpte_region.source_len) - 1, 1207 be64_to_cpu(fdm_ptr->hpte_region.source_len), 1208 be64_to_cpu(fdm_ptr->hpte_region.bytes_dumped)); 1209 seq_printf(m, 1210 "DUMP: [%#016llx-%#016llx] %#llx bytes, " 1211 "Dumped: %#llx\n", 1212 be64_to_cpu(fdm_ptr->rmr_region.destination_address), 1213 be64_to_cpu(fdm_ptr->rmr_region.destination_address) + 1214 be64_to_cpu(fdm_ptr->rmr_region.source_len) - 1, 1215 be64_to_cpu(fdm_ptr->rmr_region.source_len), 1216 be64_to_cpu(fdm_ptr->rmr_region.bytes_dumped)); 1217 1218 if (!fdm_active || 1219 (fw_dump.reserve_dump_area_start == 1220 be64_to_cpu(fdm_ptr->cpu_state_data.destination_address))) 1221 goto out; 1222 1223 /* Dump is active. Show reserved memory region. */ 1224 seq_printf(m, 1225 " : [%#016llx-%#016llx] %#llx bytes, " 1226 "Dumped: %#llx\n", 1227 (unsigned long long)fw_dump.reserve_dump_area_start, 1228 be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) - 1, 1229 be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) - 1230 fw_dump.reserve_dump_area_start, 1231 be64_to_cpu(fdm_ptr->cpu_state_data.destination_address) - 1232 fw_dump.reserve_dump_area_start); 1233 out: 1234 if (fdm_active) 1235 mutex_unlock(&fadump_mutex); 1236 return 0; 1237 } 1238 1239 static struct kobj_attribute fadump_release_attr = __ATTR(fadump_release_mem, 1240 0200, NULL, 1241 fadump_release_memory_store); 1242 static struct kobj_attribute fadump_attr = __ATTR(fadump_enabled, 1243 0444, fadump_enabled_show, 1244 NULL); 1245 static struct kobj_attribute fadump_register_attr = __ATTR(fadump_registered, 1246 0644, fadump_register_show, 1247 fadump_register_store); 1248 1249 static int fadump_region_open(struct inode *inode, struct file *file) 1250 { 1251 return single_open(file, fadump_region_show, inode->i_private); 1252 } 1253 1254 static const struct file_operations fadump_region_fops = { 1255 .open = fadump_region_open, 1256 .read = seq_read, 1257 .llseek = seq_lseek, 1258 .release = single_release, 1259 }; 1260 1261 static void fadump_init_files(void) 1262 { 1263 struct dentry *debugfs_file; 1264 int rc = 0; 1265 1266 rc = sysfs_create_file(kernel_kobj, &fadump_attr.attr); 1267 if (rc) 1268 printk(KERN_ERR "fadump: unable to create sysfs file" 1269 " fadump_enabled (%d)\n", rc); 1270 1271 rc = sysfs_create_file(kernel_kobj, &fadump_register_attr.attr); 1272 if (rc) 1273 printk(KERN_ERR "fadump: unable to create sysfs file" 1274 " fadump_registered (%d)\n", rc); 1275 1276 debugfs_file = debugfs_create_file("fadump_region", 0444, 1277 powerpc_debugfs_root, NULL, 1278 &fadump_region_fops); 1279 if (!debugfs_file) 1280 printk(KERN_ERR "fadump: unable to create debugfs file" 1281 " fadump_region\n"); 1282 1283 if (fw_dump.dump_active) { 1284 rc = sysfs_create_file(kernel_kobj, &fadump_release_attr.attr); 1285 if (rc) 1286 printk(KERN_ERR "fadump: unable to create sysfs file" 1287 " fadump_release_mem (%d)\n", rc); 1288 } 1289 return; 1290 } 1291 1292 /* 1293 * Prepare for firmware-assisted dump. 1294 */ 1295 int __init setup_fadump(void) 1296 { 1297 if (!fw_dump.fadump_enabled) 1298 return 0; 1299 1300 if (!fw_dump.fadump_supported) { 1301 printk(KERN_ERR "Firmware-assisted dump is not supported on" 1302 " this hardware\n"); 1303 return 0; 1304 } 1305 1306 fadump_show_config(); 1307 /* 1308 * If dump data is available then see if it is valid and prepare for 1309 * saving it to the disk. 1310 */ 1311 if (fw_dump.dump_active) { 1312 /* 1313 * if dump process fails then invalidate the registration 1314 * and release memory before proceeding for re-registration. 1315 */ 1316 if (process_fadump(fdm_active) < 0) 1317 fadump_invalidate_release_mem(); 1318 } 1319 /* Initialize the kernel dump memory structure for FAD registration. */ 1320 else if (fw_dump.reserve_dump_area_size) 1321 init_fadump_mem_struct(&fdm, fw_dump.reserve_dump_area_start); 1322 fadump_init_files(); 1323 1324 return 1; 1325 } 1326 subsys_initcall(setup_fadump); 1327