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TOMOYO Linux Cross Reference
Linux/arch/x86/kernel/crash.c

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  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/e820/types.h>
 33 #include <asm/io_apic.h>
 34 #include <asm/hpet.h>
 35 #include <linux/kdebug.h>
 36 #include <asm/cpu.h>
 37 #include <asm/reboot.h>
 38 #include <asm/virtext.h>
 39 #include <asm/intel_pt.h>
 40 
 41 /* Alignment required for elf header segment */
 42 #define ELF_CORE_HEADER_ALIGN   4096
 43 
 44 /* This primarily represents number of split ranges due to exclusion */
 45 #define CRASH_MAX_RANGES        16
 46 
 47 struct crash_mem_range {
 48         u64 start, end;
 49 };
 50 
 51 struct crash_mem {
 52         unsigned int nr_ranges;
 53         struct crash_mem_range ranges[CRASH_MAX_RANGES];
 54 };
 55 
 56 /* Misc data about ram ranges needed to prepare elf headers */
 57 struct crash_elf_data {
 58         struct kimage *image;
 59         /*
 60          * Total number of ram ranges we have after various adjustments for
 61          * crash reserved region, etc.
 62          */
 63         unsigned int max_nr_ranges;
 64 
 65         /* Pointer to elf header */
 66         void *ehdr;
 67         /* Pointer to next phdr */
 68         void *bufp;
 69         struct crash_mem mem;
 70 };
 71 
 72 /* Used while preparing memory map entries for second kernel */
 73 struct crash_memmap_data {
 74         struct boot_params *params;
 75         /* Type of memory */
 76         unsigned int type;
 77 };
 78 
 79 /*
 80  * This is used to VMCLEAR all VMCSs loaded on the
 81  * processor. And when loading kvm_intel module, the
 82  * callback function pointer will be assigned.
 83  *
 84  * protected by rcu.
 85  */
 86 crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss = NULL;
 87 EXPORT_SYMBOL_GPL(crash_vmclear_loaded_vmcss);
 88 unsigned long crash_zero_bytes;
 89 
 90 static inline void cpu_crash_vmclear_loaded_vmcss(void)
 91 {
 92         crash_vmclear_fn *do_vmclear_operation = NULL;
 93 
 94         rcu_read_lock();
 95         do_vmclear_operation = rcu_dereference(crash_vmclear_loaded_vmcss);
 96         if (do_vmclear_operation)
 97                 do_vmclear_operation();
 98         rcu_read_unlock();
 99 }
100 
101 #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
102 
103 static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
104 {
105 #ifdef CONFIG_X86_32
106         struct pt_regs fixed_regs;
107 
108         if (!user_mode(regs)) {
109                 crash_fixup_ss_esp(&fixed_regs, regs);
110                 regs = &fixed_regs;
111         }
112 #endif
113         crash_save_cpu(regs, cpu);
114 
115         /*
116          * VMCLEAR VMCSs loaded on all cpus if needed.
117          */
118         cpu_crash_vmclear_loaded_vmcss();
119 
120         /* Disable VMX or SVM if needed.
121          *
122          * We need to disable virtualization on all CPUs.
123          * Having VMX or SVM enabled on any CPU may break rebooting
124          * after the kdump kernel has finished its task.
125          */
126         cpu_emergency_vmxoff();
127         cpu_emergency_svm_disable();
128 
129         /*
130          * Disable Intel PT to stop its logging
131          */
132         cpu_emergency_stop_pt();
133 
134         disable_local_APIC();
135 }
136 
137 void kdump_nmi_shootdown_cpus(void)
138 {
139         nmi_shootdown_cpus(kdump_nmi_callback);
140 
141         disable_local_APIC();
142 }
143 
144 /* Override the weak function in kernel/panic.c */
145 void crash_smp_send_stop(void)
146 {
147         static int cpus_stopped;
148 
149         if (cpus_stopped)
150                 return;
151 
152         if (smp_ops.crash_stop_other_cpus)
153                 smp_ops.crash_stop_other_cpus();
154         else
155                 smp_send_stop();
156 
157         cpus_stopped = 1;
158 }
159 
160 #else
161 void crash_smp_send_stop(void)
162 {
163         /* There are no cpus to shootdown */
164 }
165 #endif
166 
167 void native_machine_crash_shutdown(struct pt_regs *regs)
168 {
169         /* This function is only called after the system
170          * has panicked or is otherwise in a critical state.
171          * The minimum amount of code to allow a kexec'd kernel
172          * to run successfully needs to happen here.
173          *
174          * In practice this means shooting down the other cpus in
175          * an SMP system.
176          */
177         /* The kernel is broken so disable interrupts */
178         local_irq_disable();
179 
180         crash_smp_send_stop();
181 
182         /*
183          * VMCLEAR VMCSs loaded on this cpu if needed.
184          */
185         cpu_crash_vmclear_loaded_vmcss();
186 
187         /* Booting kdump kernel with VMX or SVM enabled won't work,
188          * because (among other limitations) we can't disable paging
189          * with the virt flags.
190          */
191         cpu_emergency_vmxoff();
192         cpu_emergency_svm_disable();
193 
194         /*
195          * Disable Intel PT to stop its logging
196          */
197         cpu_emergency_stop_pt();
198 
199 #ifdef CONFIG_X86_IO_APIC
200         /* Prevent crash_kexec() from deadlocking on ioapic_lock. */
201         ioapic_zap_locks();
202         disable_IO_APIC();
203 #endif
204         lapic_shutdown();
205 #ifdef CONFIG_HPET_TIMER
206         hpet_disable();
207 #endif
208         crash_save_cpu(regs, safe_smp_processor_id());
209 }
210 
211 #ifdef CONFIG_KEXEC_FILE
212 static int get_nr_ram_ranges_callback(struct resource *res, void *arg)
213 {
214         unsigned int *nr_ranges = arg;
215 
216         (*nr_ranges)++;
217         return 0;
218 }
219 
220 
221 /* Gather all the required information to prepare elf headers for ram regions */
222 static void fill_up_crash_elf_data(struct crash_elf_data *ced,
223                                    struct kimage *image)
224 {
225         unsigned int nr_ranges = 0;
226 
227         ced->image = image;
228 
229         walk_system_ram_res(0, -1, &nr_ranges,
230                                 get_nr_ram_ranges_callback);
231 
232         ced->max_nr_ranges = nr_ranges;
233 
234         /* Exclusion of crash region could split memory ranges */
235         ced->max_nr_ranges++;
236 
237         /* If crashk_low_res is not 0, another range split possible */
238         if (crashk_low_res.end)
239                 ced->max_nr_ranges++;
240 }
241 
242 static int exclude_mem_range(struct crash_mem *mem,
243                 unsigned long long mstart, unsigned long long mend)
244 {
245         int i, j;
246         unsigned long long start, end;
247         struct crash_mem_range temp_range = {0, 0};
248 
249         for (i = 0; i < mem->nr_ranges; i++) {
250                 start = mem->ranges[i].start;
251                 end = mem->ranges[i].end;
252 
253                 if (mstart > end || mend < start)
254                         continue;
255 
256                 /* Truncate any area outside of range */
257                 if (mstart < start)
258                         mstart = start;
259                 if (mend > end)
260                         mend = end;
261 
262                 /* Found completely overlapping range */
263                 if (mstart == start && mend == end) {
264                         mem->ranges[i].start = 0;
265                         mem->ranges[i].end = 0;
266                         if (i < mem->nr_ranges - 1) {
267                                 /* Shift rest of the ranges to left */
268                                 for (j = i; j < mem->nr_ranges - 1; j++) {
269                                         mem->ranges[j].start =
270                                                 mem->ranges[j+1].start;
271                                         mem->ranges[j].end =
272                                                         mem->ranges[j+1].end;
273                                 }
274                         }
275                         mem->nr_ranges--;
276                         return 0;
277                 }
278 
279                 if (mstart > start && mend < end) {
280                         /* Split original range */
281                         mem->ranges[i].end = mstart - 1;
282                         temp_range.start = mend + 1;
283                         temp_range.end = end;
284                 } else if (mstart != start)
285                         mem->ranges[i].end = mstart - 1;
286                 else
287                         mem->ranges[i].start = mend + 1;
288                 break;
289         }
290 
291         /* If a split happend, add the split to array */
292         if (!temp_range.end)
293                 return 0;
294 
295         /* Split happened */
296         if (i == CRASH_MAX_RANGES - 1) {
297                 pr_err("Too many crash ranges after split\n");
298                 return -ENOMEM;
299         }
300 
301         /* Location where new range should go */
302         j = i + 1;
303         if (j < mem->nr_ranges) {
304                 /* Move over all ranges one slot towards the end */
305                 for (i = mem->nr_ranges - 1; i >= j; i--)
306                         mem->ranges[i + 1] = mem->ranges[i];
307         }
308 
309         mem->ranges[j].start = temp_range.start;
310         mem->ranges[j].end = temp_range.end;
311         mem->nr_ranges++;
312         return 0;
313 }
314 
315 /*
316  * Look for any unwanted ranges between mstart, mend and remove them. This
317  * might lead to split and split ranges are put in ced->mem.ranges[] array
318  */
319 static int elf_header_exclude_ranges(struct crash_elf_data *ced,
320                 unsigned long long mstart, unsigned long long mend)
321 {
322         struct crash_mem *cmem = &ced->mem;
323         int ret = 0;
324 
325         memset(cmem->ranges, 0, sizeof(cmem->ranges));
326 
327         cmem->ranges[0].start = mstart;
328         cmem->ranges[0].end = mend;
329         cmem->nr_ranges = 1;
330 
331         /* Exclude crashkernel region */
332         ret = exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
333         if (ret)
334                 return ret;
335 
336         if (crashk_low_res.end) {
337                 ret = exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
338                 if (ret)
339                         return ret;
340         }
341 
342         return ret;
343 }
344 
345 static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg)
346 {
347         struct crash_elf_data *ced = arg;
348         Elf64_Ehdr *ehdr;
349         Elf64_Phdr *phdr;
350         unsigned long mstart, mend;
351         struct kimage *image = ced->image;
352         struct crash_mem *cmem;
353         int ret, i;
354 
355         ehdr = ced->ehdr;
356 
357         /* Exclude unwanted mem ranges */
358         ret = elf_header_exclude_ranges(ced, res->start, res->end);
359         if (ret)
360                 return ret;
361 
362         /* Go through all the ranges in ced->mem.ranges[] and prepare phdr */
363         cmem = &ced->mem;
364 
365         for (i = 0; i < cmem->nr_ranges; i++) {
366                 mstart = cmem->ranges[i].start;
367                 mend = cmem->ranges[i].end;
368 
369                 phdr = ced->bufp;
370                 ced->bufp += sizeof(Elf64_Phdr);
371 
372                 phdr->p_type = PT_LOAD;
373                 phdr->p_flags = PF_R|PF_W|PF_X;
374                 phdr->p_offset  = mstart;
375 
376                 /*
377                  * If a range matches backup region, adjust offset to backup
378                  * segment.
379                  */
380                 if (mstart == image->arch.backup_src_start &&
381                     (mend - mstart + 1) == image->arch.backup_src_sz)
382                         phdr->p_offset = image->arch.backup_load_addr;
383 
384                 phdr->p_paddr = mstart;
385                 phdr->p_vaddr = (unsigned long long) __va(mstart);
386                 phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
387                 phdr->p_align = 0;
388                 ehdr->e_phnum++;
389                 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",
390                         phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
391                         ehdr->e_phnum, phdr->p_offset);
392         }
393 
394         return ret;
395 }
396 
397 static int prepare_elf64_headers(struct crash_elf_data *ced,
398                 void **addr, unsigned long *sz)
399 {
400         Elf64_Ehdr *ehdr;
401         Elf64_Phdr *phdr;
402         unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
403         unsigned char *buf, *bufp;
404         unsigned int cpu;
405         unsigned long long notes_addr;
406         int ret;
407 
408         /* extra phdr for vmcoreinfo elf note */
409         nr_phdr = nr_cpus + 1;
410         nr_phdr += ced->max_nr_ranges;
411 
412         /*
413          * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
414          * area on x86_64 (ffffffff80000000 - ffffffffa0000000).
415          * I think this is required by tools like gdb. So same physical
416          * memory will be mapped in two elf headers. One will contain kernel
417          * text virtual addresses and other will have __va(physical) addresses.
418          */
419 
420         nr_phdr++;
421         elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
422         elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
423 
424         buf = vzalloc(elf_sz);
425         if (!buf)
426                 return -ENOMEM;
427 
428         bufp = buf;
429         ehdr = (Elf64_Ehdr *)bufp;
430         bufp += sizeof(Elf64_Ehdr);
431         memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
432         ehdr->e_ident[EI_CLASS] = ELFCLASS64;
433         ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
434         ehdr->e_ident[EI_VERSION] = EV_CURRENT;
435         ehdr->e_ident[EI_OSABI] = ELF_OSABI;
436         memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
437         ehdr->e_type = ET_CORE;
438         ehdr->e_machine = ELF_ARCH;
439         ehdr->e_version = EV_CURRENT;
440         ehdr->e_phoff = sizeof(Elf64_Ehdr);
441         ehdr->e_ehsize = sizeof(Elf64_Ehdr);
442         ehdr->e_phentsize = sizeof(Elf64_Phdr);
443 
444         /* Prepare one phdr of type PT_NOTE for each present cpu */
445         for_each_present_cpu(cpu) {
446                 phdr = (Elf64_Phdr *)bufp;
447                 bufp += sizeof(Elf64_Phdr);
448                 phdr->p_type = PT_NOTE;
449                 notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
450                 phdr->p_offset = phdr->p_paddr = notes_addr;
451                 phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
452                 (ehdr->e_phnum)++;
453         }
454 
455         /* Prepare one PT_NOTE header for vmcoreinfo */
456         phdr = (Elf64_Phdr *)bufp;
457         bufp += sizeof(Elf64_Phdr);
458         phdr->p_type = PT_NOTE;
459         phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
460         phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;
461         (ehdr->e_phnum)++;
462 
463 #ifdef CONFIG_X86_64
464         /* Prepare PT_LOAD type program header for kernel text region */
465         phdr = (Elf64_Phdr *)bufp;
466         bufp += sizeof(Elf64_Phdr);
467         phdr->p_type = PT_LOAD;
468         phdr->p_flags = PF_R|PF_W|PF_X;
469         phdr->p_vaddr = (Elf64_Addr)_text;
470         phdr->p_filesz = phdr->p_memsz = _end - _text;
471         phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
472         (ehdr->e_phnum)++;
473 #endif
474 
475         /* Prepare PT_LOAD headers for system ram chunks. */
476         ced->ehdr = ehdr;
477         ced->bufp = bufp;
478         ret = walk_system_ram_res(0, -1, ced,
479                         prepare_elf64_ram_headers_callback);
480         if (ret < 0)
481                 return ret;
482 
483         *addr = buf;
484         *sz = elf_sz;
485         return 0;
486 }
487 
488 /* Prepare elf headers. Return addr and size */
489 static int prepare_elf_headers(struct kimage *image, void **addr,
490                                         unsigned long *sz)
491 {
492         struct crash_elf_data *ced;
493         int ret;
494 
495         ced = kzalloc(sizeof(*ced), GFP_KERNEL);
496         if (!ced)
497                 return -ENOMEM;
498 
499         fill_up_crash_elf_data(ced, image);
500 
501         /* By default prepare 64bit headers */
502         ret =  prepare_elf64_headers(ced, addr, sz);
503         kfree(ced);
504         return ret;
505 }
506 
507 static int add_e820_entry(struct boot_params *params, struct e820_entry *entry)
508 {
509         unsigned int nr_e820_entries;
510 
511         nr_e820_entries = params->e820_entries;
512         if (nr_e820_entries >= E820_MAX_ENTRIES_ZEROPAGE)
513                 return 1;
514 
515         memcpy(&params->e820_table[nr_e820_entries], entry,
516                         sizeof(struct e820_entry));
517         params->e820_entries++;
518         return 0;
519 }
520 
521 static int memmap_entry_callback(struct resource *res, void *arg)
522 {
523         struct crash_memmap_data *cmd = arg;
524         struct boot_params *params = cmd->params;
525         struct e820_entry ei;
526 
527         ei.addr = res->start;
528         ei.size = resource_size(res);
529         ei.type = cmd->type;
530         add_e820_entry(params, &ei);
531 
532         return 0;
533 }
534 
535 static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem,
536                                  unsigned long long mstart,
537                                  unsigned long long mend)
538 {
539         unsigned long start, end;
540         int ret = 0;
541 
542         cmem->ranges[0].start = mstart;
543         cmem->ranges[0].end = mend;
544         cmem->nr_ranges = 1;
545 
546         /* Exclude Backup region */
547         start = image->arch.backup_load_addr;
548         end = start + image->arch.backup_src_sz - 1;
549         ret = exclude_mem_range(cmem, start, end);
550         if (ret)
551                 return ret;
552 
553         /* Exclude elf header region */
554         start = image->arch.elf_load_addr;
555         end = start + image->arch.elf_headers_sz - 1;
556         return exclude_mem_range(cmem, start, end);
557 }
558 
559 /* Prepare memory map for crash dump kernel */
560 int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params)
561 {
562         int i, ret = 0;
563         unsigned long flags;
564         struct e820_entry ei;
565         struct crash_memmap_data cmd;
566         struct crash_mem *cmem;
567 
568         cmem = vzalloc(sizeof(struct crash_mem));
569         if (!cmem)
570                 return -ENOMEM;
571 
572         memset(&cmd, 0, sizeof(struct crash_memmap_data));
573         cmd.params = params;
574 
575         /* Add first 640K segment */
576         ei.addr = image->arch.backup_src_start;
577         ei.size = image->arch.backup_src_sz;
578         ei.type = E820_TYPE_RAM;
579         add_e820_entry(params, &ei);
580 
581         /* Add ACPI tables */
582         cmd.type = E820_TYPE_ACPI;
583         flags = IORESOURCE_MEM | IORESOURCE_BUSY;
584         walk_iomem_res_desc(IORES_DESC_ACPI_TABLES, flags, 0, -1, &cmd,
585                        memmap_entry_callback);
586 
587         /* Add ACPI Non-volatile Storage */
588         cmd.type = E820_TYPE_NVS;
589         walk_iomem_res_desc(IORES_DESC_ACPI_NV_STORAGE, flags, 0, -1, &cmd,
590                         memmap_entry_callback);
591 
592         /* Add crashk_low_res region */
593         if (crashk_low_res.end) {
594                 ei.addr = crashk_low_res.start;
595                 ei.size = crashk_low_res.end - crashk_low_res.start + 1;
596                 ei.type = E820_TYPE_RAM;
597                 add_e820_entry(params, &ei);
598         }
599 
600         /* Exclude some ranges from crashk_res and add rest to memmap */
601         ret = memmap_exclude_ranges(image, cmem, crashk_res.start,
602                                                 crashk_res.end);
603         if (ret)
604                 goto out;
605 
606         for (i = 0; i < cmem->nr_ranges; i++) {
607                 ei.size = cmem->ranges[i].end - cmem->ranges[i].start + 1;
608 
609                 /* If entry is less than a page, skip it */
610                 if (ei.size < PAGE_SIZE)
611                         continue;
612                 ei.addr = cmem->ranges[i].start;
613                 ei.type = E820_TYPE_RAM;
614                 add_e820_entry(params, &ei);
615         }
616 
617 out:
618         vfree(cmem);
619         return ret;
620 }
621 
622 static int determine_backup_region(struct resource *res, void *arg)
623 {
624         struct kimage *image = arg;
625 
626         image->arch.backup_src_start = res->start;
627         image->arch.backup_src_sz = resource_size(res);
628 
629         /* Expecting only one range for backup region */
630         return 1;
631 }
632 
633 int crash_load_segments(struct kimage *image)
634 {
635         int ret;
636         struct kexec_buf kbuf = { .image = image, .buf_min = 0,
637                                   .buf_max = ULONG_MAX, .top_down = false };
638 
639         /*
640          * Determine and load a segment for backup area. First 640K RAM
641          * region is backup source
642          */
643 
644         ret = walk_system_ram_res(KEXEC_BACKUP_SRC_START, KEXEC_BACKUP_SRC_END,
645                                 image, determine_backup_region);
646 
647         /* Zero or postive return values are ok */
648         if (ret < 0)
649                 return ret;
650 
651         /* Add backup segment. */
652         if (image->arch.backup_src_sz) {
653                 kbuf.buffer = &crash_zero_bytes;
654                 kbuf.bufsz = sizeof(crash_zero_bytes);
655                 kbuf.memsz = image->arch.backup_src_sz;
656                 kbuf.buf_align = PAGE_SIZE;
657                 /*
658                  * Ideally there is no source for backup segment. This is
659                  * copied in purgatory after crash. Just add a zero filled
660                  * segment for now to make sure checksum logic works fine.
661                  */
662                 ret = kexec_add_buffer(&kbuf);
663                 if (ret)
664                         return ret;
665                 image->arch.backup_load_addr = kbuf.mem;
666                 pr_debug("Loaded backup region at 0x%lx backup_start=0x%lx memsz=0x%lx\n",
667                          image->arch.backup_load_addr,
668                          image->arch.backup_src_start, kbuf.memsz);
669         }
670 
671         /* Prepare elf headers and add a segment */
672         ret = prepare_elf_headers(image, &kbuf.buffer, &kbuf.bufsz);
673         if (ret)
674                 return ret;
675 
676         image->arch.elf_headers = kbuf.buffer;
677         image->arch.elf_headers_sz = kbuf.bufsz;
678 
679         kbuf.memsz = kbuf.bufsz;
680         kbuf.buf_align = ELF_CORE_HEADER_ALIGN;
681         ret = kexec_add_buffer(&kbuf);
682         if (ret) {
683                 vfree((void *)image->arch.elf_headers);
684                 return ret;
685         }
686         image->arch.elf_load_addr = kbuf.mem;
687         pr_debug("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
688                  image->arch.elf_load_addr, kbuf.bufsz, kbuf.bufsz);
689 
690         return ret;
691 }
692 #endif /* CONFIG_KEXEC_FILE */
693 

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