arch/x86/kernel/crash.c

   1 /*
   2  * Architecture specific (i386/x86_64) functions for kexec based crash dumps.
   3  *
   4  * Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
   5  *
   6  * Copyright (C) IBM Corporation, 2004. All rights reserved.
   7  * Copyright (C) Red Hat Inc., 2014. All rights reserved.
   8  * Authors:
   9  *      Vivek Goyal <vgoyal@redhat.com>
  10  *
  11  */
  12
  13 #define pr_fmt(fmt)     "kexec: " fmt
  14
  15 #include <linux/types.h>
  16 #include <linux/kernel.h>
  17 #include <linux/smp.h>
  18 #include <linux/reboot.h>
  19 #include <linux/kexec.h>
  20 #include <linux/delay.h>
  21 #include <linux/elf.h>
  22 #include <linux/elfcore.h>
  23 #include <linux/export.h>
  24 #include <linux/slab.h>
  25 #include <linux/vmalloc.h>
  26
  27 #include <asm/processor.h>
  28 #include <asm/hardirq.h>
  29 #include <asm/nmi.h>
  30 #include <asm/hw_irq.h>
  31 #include <asm/apic.h>
  32 #include <asm/io_apic.h>
  33 #include <asm/hpet.h>
  34 #include <linux/kdebug.h>
  35 #include <asm/cpu.h>
  36 #include <asm/reboot.h>
  37 #include <asm/virtext.h>
  38 #include <asm/intel_pt.h>
  39
  40 /* Alignment required for elf header segment */
  41 #define ELF_CORE_HEADER_ALIGN   4096
  42
  43 /* This primarily represents number of split ranges due to exclusion */
  44 #define CRASH_MAX_RANGES        16
  45
  46 struct crash_mem_range {
  47         u64 start, end;
  48 };
  49
  50 struct crash_mem {
  51         unsigned int nr_ranges;
  52         struct crash_mem_range ranges[CRASH_MAX_RANGES];
  53 };
  54
  55 /* Misc data about ram ranges needed to prepare elf headers */
  56 struct crash_elf_data {
  57         struct kimage *image;
  58         /*
  59          * Total number of ram ranges we have after various adjustments for
  60          * crash reserved region, etc.
  61          */
  62         unsigned int max_nr_ranges;
  63
  64         /* Pointer to elf header */
  65         void *ehdr;
  66         /* Pointer to next phdr */
  67         void *bufp;
  68         struct crash_mem mem;
  69 };
  70
  71 /* Used while preparing memory map entries for second kernel */
  72 struct crash_memmap_data {
  73         struct boot_params *params;
  74         /* Type of memory */
  75         unsigned int type;
  76 };
  77
  78 /*
  79  * This is used to VMCLEAR all VMCSs loaded on the
  80  * processor. And when loading kvm_intel module, the
  81  * callback function pointer will be assigned.
  82  *
  83  * protected by rcu.
  84  */
  85 crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss = NULL;
  86 EXPORT_SYMBOL_GPL(crash_vmclear_loaded_vmcss);
  87 unsigned long crash_zero_bytes;
  88
  89 static inline void cpu_crash_vmclear_loaded_vmcss(void)
  90 {
  91         crash_vmclear_fn *do_vmclear_operation = NULL;
  92
  93         rcu_read_lock();
  94         do_vmclear_operation = rcu_dereference(crash_vmclear_loaded_vmcss);
  95         if (do_vmclear_operation)
  96                 do_vmclear_operation();
  97         rcu_read_unlock();
  98 }
  99
 100 #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
 101
 102 static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
 103 {
 104 #ifdef CONFIG_X86_32
 105         struct pt_regs fixed_regs;
 106
 107         if (!user_mode(regs)) {
 108                 crash_fixup_ss_esp(&fixed_regs, regs);
 109                 regs = &fixed_regs;
 110         }
 111 #endif
 112         crash_save_cpu(regs, cpu);
 113
 114         /*
 115          * VMCLEAR VMCSs loaded on all cpus if needed.
 116          */
 117         cpu_crash_vmclear_loaded_vmcss();
 118
 119         /* Disable VMX or SVM if needed.
 120          *
 121          * We need to disable virtualization on all CPUs.
 122          * Having VMX or SVM enabled on any CPU may break rebooting
 123          * after the kdump kernel has finished its task.
 124          */
 125         cpu_emergency_vmxoff();
 126         cpu_emergency_svm_disable();
 127
 128         /*
 129          * Disable Intel PT to stop its logging
 130          */
 131         cpu_emergency_stop_pt();
 132
 133         disable_local_APIC();
 134 }
 135
 136 static void kdump_nmi_shootdown_cpus(void)
 137 {
 138         nmi_shootdown_cpus(kdump_nmi_callback);
 139
 140         disable_local_APIC();
 141 }
 142
 143 #else
 144 static void kdump_nmi_shootdown_cpus(void)
 145 {
 146         /* There are no cpus to shootdown */
 147 }
 148 #endif
 149
 150 void native_machine_crash_shutdown(struct pt_regs *regs)
 151 {
 152         /* This function is only called after the system
 153          * has panicked or is otherwise in a critical state.
 154          * The minimum amount of code to allow a kexec'd kernel
 155          * to run successfully needs to happen here.
 156          *
 157          * In practice this means shooting down the other cpus in
 158          * an SMP system.
 159          */
 160         /* The kernel is broken so disable interrupts */
 161         local_irq_disable();
 162
 163         kdump_nmi_shootdown_cpus();
 164
 165         /*
 166          * VMCLEAR VMCSs loaded on this cpu if needed.
 167          */
 168         cpu_crash_vmclear_loaded_vmcss();
 169
 170         /* Booting kdump kernel with VMX or SVM enabled won't work,
 171          * because (among other limitations) we can't disable paging
 172          * with the virt flags.
 173          */
 174         cpu_emergency_vmxoff();
 175         cpu_emergency_svm_disable();
 176
 177         /*
 178          * Disable Intel PT to stop its logging
 179          */
 180         cpu_emergency_stop_pt();
 181
 182 #ifdef CONFIG_X86_IO_APIC
 183         /* Prevent crash_kexec() from deadlocking on ioapic_lock. */
 184         ioapic_zap_locks();
 185         disable_IO_APIC();
 186 #endif
 187         lapic_shutdown();
 188 #ifdef CONFIG_HPET_TIMER
 189         hpet_disable();
 190 #endif
 191         crash_save_cpu(regs, safe_smp_processor_id());
 192 }
 193
 194 #ifdef CONFIG_KEXEC_FILE
 195 static int get_nr_ram_ranges_callback(u64 start, u64 end, void *arg)
 196 {
 197         unsigned int *nr_ranges = arg;
 198
 199         (*nr_ranges)++;
 200         return 0;
 201 }
 202
 203
 204 /* Gather all the required information to prepare elf headers for ram regions */
 205 static void fill_up_crash_elf_data(struct crash_elf_data *ced,
 206                                    struct kimage *image)
 207 {
 208         unsigned int nr_ranges = 0;
 209
 210         ced->image = image;
 211
 212         walk_system_ram_res(0, -1, &nr_ranges,
 213                                 get_nr_ram_ranges_callback);
 214
 215         ced->max_nr_ranges = nr_ranges;
 216
 217         /* Exclusion of crash region could split memory ranges */
 218         ced->max_nr_ranges++;
 219
 220         /* If crashk_low_res is not 0, another range split possible */
 221         if (crashk_low_res.end)
 222                 ced->max_nr_ranges++;
 223 }
 224
 225 static int exclude_mem_range(struct crash_mem *mem,
 226                 unsigned long long mstart, unsigned long long mend)
 227 {
 228         int i, j;
 229         unsigned long long start, end;
 230         struct crash_mem_range temp_range = {0, 0};
 231
 232         for (i = 0; i < mem->nr_ranges; i++) {
 233                 start = mem->ranges[i].start;
 234                 end = mem->ranges[i].end;
 235
 236                 if (mstart > end || mend < start)
 237                         continue;
 238
 239                 /* Truncate any area outside of range */
 240                 if (mstart < start)
 241                         mstart = start;
 242                 if (mend > end)
 243                         mend = end;
 244
 245                 /* Found completely overlapping range */
 246                 if (mstart == start && mend == end) {
 247                         mem->ranges[i].start = 0;
 248                         mem->ranges[i].end = 0;
 249                         if (i < mem->nr_ranges - 1) {
 250                                 /* Shift rest of the ranges to left */
 251                                 for (j = i; j < mem->nr_ranges - 1; j++) {
 252                                         mem->ranges[j].start =
 253                                                 mem->ranges[j+1].start;
 254                                         mem->ranges[j].end =
 255                                                         mem->ranges[j+1].end;
 256                                 }
 257                         }
 258                         mem->nr_ranges--;
 259                         return 0;
 260                 }
 261
 262                 if (mstart > start && mend < end) {
 263                         /* Split original range */
 264                         mem->ranges[i].end = mstart - 1;
 265                         temp_range.start = mend + 1;
 266                         temp_range.end = end;
 267                 } else if (mstart != start)
 268                         mem->ranges[i].end = mstart - 1;
 269                 else
 270                         mem->ranges[i].start = mend + 1;
 271                 break;
 272         }
 273
 274         /* If a split happend, add the split to array */
 275         if (!temp_range.end)
 276                 return 0;
 277
 278         /* Split happened */
 279         if (i == CRASH_MAX_RANGES - 1) {
 280                 pr_err("Too many crash ranges after split\n");
 281                 return -ENOMEM;
 282         }
 283
 284         /* Location where new range should go */
 285         j = i + 1;
 286         if (j < mem->nr_ranges) {
 287                 /* Move over all ranges one slot towards the end */
 288                 for (i = mem->nr_ranges - 1; i >= j; i--)
 289                         mem->ranges[i + 1] = mem->ranges[i];
 290         }
 291
 292         mem->ranges[j].start = temp_range.start;
 293         mem->ranges[j].end = temp_range.end;
 294         mem->nr_ranges++;
 295         return 0;
 296 }
 297
 298 /*
 299  * Look for any unwanted ranges between mstart, mend and remove them. This
 300  * might lead to split and split ranges are put in ced->mem.ranges[] array
 301  */
 302 static int elf_header_exclude_ranges(struct crash_elf_data *ced,
 303                 unsigned long long mstart, unsigned long long mend)
 304 {
 305         struct crash_mem *cmem = &ced->mem;
 306         int ret = 0;
 307
 308         memset(cmem->ranges, 0, sizeof(cmem->ranges));
 309
 310         cmem->ranges[0].start = mstart;
 311         cmem->ranges[0].end = mend;
 312         cmem->nr_ranges = 1;
 313
 314         /* Exclude crashkernel region */
 315         ret = exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
 316         if (ret)
 317                 return ret;
 318
 319         if (crashk_low_res.end) {
 320                 ret = exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
 321                 if (ret)
 322                         return ret;
 323         }
 324
 325         return ret;
 326 }
 327
 328 static int prepare_elf64_ram_headers_callback(u64 start, u64 end, void *arg)
 329 {
 330         struct crash_elf_data *ced = arg;
 331         Elf64_Ehdr *ehdr;
 332         Elf64_Phdr *phdr;
 333         unsigned long mstart, mend;
 334         struct kimage *image = ced->image;
 335         struct crash_mem *cmem;
 336         int ret, i;
 337
 338         ehdr = ced->ehdr;
 339
 340         /* Exclude unwanted mem ranges */
 341         ret = elf_header_exclude_ranges(ced, start, end);
 342         if (ret)
 343                 return ret;
 344
 345         /* Go through all the ranges in ced->mem.ranges[] and prepare phdr */
 346         cmem = &ced->mem;
 347
 348         for (i = 0; i < cmem->nr_ranges; i++) {
 349                 mstart = cmem->ranges[i].start;
 350                 mend = cmem->ranges[i].end;
 351
 352                 phdr = ced->bufp;
 353                 ced->bufp += sizeof(Elf64_Phdr);
 354
 355                 phdr->p_type = PT_LOAD;
 356                 phdr->p_flags = PF_R|PF_W|PF_X;
 357                 phdr->p_offset  = mstart;
 358
 359                 /*
 360                  * If a range matches backup region, adjust offset to backup
 361                  * segment.
 362                  */
 363                 if (mstart == image->arch.backup_src_start &&
 364                     (mend - mstart + 1) == image->arch.backup_src_sz)
 365                         phdr->p_offset = image->arch.backup_load_addr;
 366
 367                 phdr->p_paddr = mstart;
 368                 phdr->p_vaddr = (unsigned long long) __va(mstart);
 369                 phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
 370                 phdr->p_align = 0;
 371                 ehdr->e_phnum++;
 372                 pr_debug("Crash PT_LOAD elf header. phdr=%p vaddr=0x%llx, paddr=0x%llx, sz=0x%llx e_phnum=%d p_offset=0x%llx\n",
 373                         phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
 374                         ehdr->e_phnum, phdr->p_offset);
 375         }
 376
 377         return ret;
 378 }
 379
 380 static int prepare_elf64_headers(struct crash_elf_data *ced,
 381                 void **addr, unsigned long *sz)
 382 {
 383         Elf64_Ehdr *ehdr;
 384         Elf64_Phdr *phdr;
 385         unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
 386         unsigned char *buf, *bufp;
 387         unsigned int cpu;
 388         unsigned long long notes_addr;
 389         int ret;
 390
 391         /* extra phdr for vmcoreinfo elf note */
 392         nr_phdr = nr_cpus + 1;
 393         nr_phdr += ced->max_nr_ranges;
 394
 395         /*
 396          * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
 397          * area on x86_64 (ffffffff80000000 - ffffffffa0000000).
 398          * I think this is required by tools like gdb. So same physical
 399          * memory will be mapped in two elf headers. One will contain kernel
 400          * text virtual addresses and other will have __va(physical) addresses.
 401          */
 402
 403         nr_phdr++;
 404         elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
 405         elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
 406
 407         buf = vzalloc(elf_sz);
 408         if (!buf)
 409                 return -ENOMEM;
 410
 411         bufp = buf;
 412         ehdr = (Elf64_Ehdr *)bufp;
 413         bufp += sizeof(Elf64_Ehdr);
 414         memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
 415         ehdr->e_ident[EI_CLASS] = ELFCLASS64;
 416         ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
 417         ehdr->e_ident[EI_VERSION] = EV_CURRENT;
 418         ehdr->e_ident[EI_OSABI] = ELF_OSABI;
 419         memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
 420         ehdr->e_type = ET_CORE;
 421         ehdr->e_machine = ELF_ARCH;
 422         ehdr->e_version = EV_CURRENT;
 423         ehdr->e_phoff = sizeof(Elf64_Ehdr);
 424         ehdr->e_ehsize = sizeof(Elf64_Ehdr);
 425         ehdr->e_phentsize = sizeof(Elf64_Phdr);
 426
 427         /* Prepare one phdr of type PT_NOTE for each present cpu */
 428         for_each_present_cpu(cpu) {
 429                 phdr = (Elf64_Phdr *)bufp;
 430                 bufp += sizeof(Elf64_Phdr);
 431                 phdr->p_type = PT_NOTE;
 432                 notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
 433                 phdr->p_offset = phdr->p_paddr = notes_addr;
 434                 phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
 435                 (ehdr->e_phnum)++;
 436         }
 437
 438         /* Prepare one PT_NOTE header for vmcoreinfo */
 439         phdr = (Elf64_Phdr *)bufp;
 440         bufp += sizeof(Elf64_Phdr);
 441         phdr->p_type = PT_NOTE;
 442         phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
 443         phdr->p_filesz = phdr->p_memsz = sizeof(vmcoreinfo_note);
 444         (ehdr->e_phnum)++;
 445
 446 #ifdef CONFIG_X86_64
 447         /* Prepare PT_LOAD type program header for kernel text region */
 448         phdr = (Elf64_Phdr *)bufp;
 449         bufp += sizeof(Elf64_Phdr);
 450         phdr->p_type = PT_LOAD;
 451         phdr->p_flags = PF_R|PF_W|PF_X;
 452         phdr->p_vaddr = (Elf64_Addr)_text;
 453         phdr->p_filesz = phdr->p_memsz = _end - _text;
 454         phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
 455         (ehdr->e_phnum)++;
 456 #endif
 457
 458         /* Prepare PT_LOAD headers for system ram chunks. */
 459         ced->ehdr = ehdr;
 460         ced->bufp = bufp;
 461         ret = walk_system_ram_res(0, -1, ced,
 462                         prepare_elf64_ram_headers_callback);
 463         if (ret < 0)
 464                 return ret;
 465
 466         *addr = buf;
 467         *sz = elf_sz;
 468         return 0;
 469 }
 470
 471 /* Prepare elf headers. Return addr and size */
 472 static int prepare_elf_headers(struct kimage *image, void **addr,
 473                                         unsigned long *sz)
 474 {
 475         struct crash_elf_data *ced;
 476         int ret;
 477
 478         ced = kzalloc(sizeof(*ced), GFP_KERNEL);
 479         if (!ced)
 480                 return -ENOMEM;
 481
 482         fill_up_crash_elf_data(ced, image);
 483
 484         /* By default prepare 64bit headers */
 485         ret =  prepare_elf64_headers(ced, addr, sz);
 486         kfree(ced);
 487         return ret;
 488 }
 489
 490 static int add_e820_entry(struct boot_params *params, struct e820entry *entry)
 491 {
 492         unsigned int nr_e820_entries;
 493
 494         nr_e820_entries = params->e820_entries;
 495         if (nr_e820_entries >= E820MAX)
 496                 return 1;
 497
 498         memcpy(&params->e820_map[nr_e820_entries], entry,
 499                         sizeof(struct e820entry));
 500         params->e820_entries++;
 501         return 0;
 502 }
 503
 504 static int memmap_entry_callback(u64 start, u64 end, void *arg)
 505 {
 506         struct crash_memmap_data *cmd = arg;
 507         struct boot_params *params = cmd->params;
 508         struct e820entry ei;
 509
 510         ei.addr = start;
 511         ei.size = end - start + 1;
 512         ei.type = cmd->type;
 513         add_e820_entry(params, &ei);
 514
 515         return 0;
 516 }
 517
 518 static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem,
 519                                  unsigned long long mstart,
 520                                  unsigned long long mend)
 521 {
 522         unsigned long start, end;
 523         int ret = 0;
 524
 525         cmem->ranges[0].start = mstart;
 526         cmem->ranges[0].end = mend;
 527         cmem->nr_ranges = 1;
 528
 529         /* Exclude Backup region */
 530         start = image->arch.backup_load_addr;
 531         end = start + image->arch.backup_src_sz - 1;
 532         ret = exclude_mem_range(cmem, start, end);
 533         if (ret)
 534                 return ret;
 535
 536         /* Exclude elf header region */
 537         start = image->arch.elf_load_addr;
 538         end = start + image->arch.elf_headers_sz - 1;
 539         return exclude_mem_range(cmem, start, end);
 540 }
 541
 542 /* Prepare memory map for crash dump kernel */
 543 int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params)
 544 {
 545         int i, ret = 0;
 546         unsigned long flags;
 547         struct e820entry ei;
 548         struct crash_memmap_data cmd;
 549         struct crash_mem *cmem;
 550
 551         cmem = vzalloc(sizeof(struct crash_mem));
 552         if (!cmem)
 553                 return -ENOMEM;
 554
 555         memset(&cmd, 0, sizeof(struct crash_memmap_data));
 556         cmd.params = params;
 557
 558         /* Add first 640K segment */
 559         ei.addr = image->arch.backup_src_start;
 560         ei.size = image->arch.backup_src_sz;
 561         ei.type = E820_RAM;
 562         add_e820_entry(params, &ei);
 563
 564         /* Add ACPI tables */
 565         cmd.type = E820_ACPI;
 566         flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 567         walk_iomem_res_desc(IORES_DESC_ACPI_TABLES, flags, 0, -1, &cmd,
 568                        memmap_entry_callback);
 569
 570         /* Add ACPI Non-volatile Storage */
 571         cmd.type = E820_NVS;
 572         walk_iomem_res_desc(IORES_DESC_ACPI_NV_STORAGE, flags, 0, -1, &cmd,
 573                         memmap_entry_callback);
 574
 575         /* Add crashk_low_res region */
 576         if (crashk_low_res.end) {
 577                 ei.addr = crashk_low_res.start;
 578                 ei.size = crashk_low_res.end - crashk_low_res.start + 1;
 579                 ei.type = E820_RAM;
 580                 add_e820_entry(params, &ei);
 581         }
 582
 583         /* Exclude some ranges from crashk_res and add rest to memmap */
 584         ret = memmap_exclude_ranges(image, cmem, crashk_res.start,
 585                                                 crashk_res.end);
 586         if (ret)
 587                 goto out;
 588
 589         for (i = 0; i < cmem->nr_ranges; i++) {
 590                 ei.size = cmem->ranges[i].end - cmem->ranges[i].start + 1;
 591
 592                 /* If entry is less than a page, skip it */
 593                 if (ei.size < PAGE_SIZE)
 594                         continue;
 595                 ei.addr = cmem->ranges[i].start;
 596                 ei.type = E820_RAM;
 597                 add_e820_entry(params, &ei);
 598         }
 599
 600 out:
 601         vfree(cmem);
 602         return ret;
 603 }
 604
 605 static int determine_backup_region(u64 start, u64 end, void *arg)
 606 {
 607         struct kimage *image = arg;
 608
 609         image->arch.backup_src_start = start;
 610         image->arch.backup_src_sz = end - start + 1;
 611
 612         /* Expecting only one range for backup region */
 613         return 1;
 614 }
 615
 616 int crash_load_segments(struct kimage *image)
 617 {
 618         unsigned long src_start, src_sz, elf_sz;
 619         void *elf_addr;
 620         int ret;
 621
 622         /*
 623          * Determine and load a segment for backup area. First 640K RAM
 624          * region is backup source
 625          */
 626
 627         ret = walk_system_ram_res(KEXEC_BACKUP_SRC_START, KEXEC_BACKUP_SRC_END,
 628                                 image, determine_backup_region);
 629
 630         /* Zero or postive return values are ok */
 631         if (ret < 0)
 632                 return ret;
 633
 634         src_start = image->arch.backup_src_start;
 635         src_sz = image->arch.backup_src_sz;
 636
 637         /* Add backup segment. */
 638         if (src_sz) {
 639                 /*
 640                  * Ideally there is no source for backup segment. This is
 641                  * copied in purgatory after crash. Just add a zero filled
 642                  * segment for now to make sure checksum logic works fine.
 643                  */
 644                 ret = kexec_add_buffer(image, (char *)&crash_zero_bytes,
 645                                        sizeof(crash_zero_bytes), src_sz,
 646                                        PAGE_SIZE, 0, -1, 0,
 647                                        &image->arch.backup_load_addr);
 648                 if (ret)
 649                         return ret;
 650                 pr_debug("Loaded backup region at 0x%lx backup_start=0x%lx memsz=0x%lx\n",
 651                          image->arch.backup_load_addr, src_start, src_sz);
 652         }
 653
 654         /* Prepare elf headers and add a segment */
 655         ret = prepare_elf_headers(image, &elf_addr, &elf_sz);
 656         if (ret)
 657                 return ret;
 658
 659         image->arch.elf_headers = elf_addr;
 660         image->arch.elf_headers_sz = elf_sz;
 661
 662         ret = kexec_add_buffer(image, (char *)elf_addr, elf_sz, elf_sz,
 663                         ELF_CORE_HEADER_ALIGN, 0, -1, 0,
 664                         &image->arch.elf_load_addr);
 665         if (ret) {
 666                 vfree((void *)image->arch.elf_headers);
 667                 return ret;
 668         }
 669         pr_debug("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
 670                  image->arch.elf_load_addr, elf_sz, elf_sz);
 671
 672         return ret;
 673 }
 674 #endif /* CONFIG_KEXEC_FILE */