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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/module.h>
 24 #include <linux/slab.h>
 25 
 26 #include <asm/processor.h>
 27 #include <asm/hardirq.h>
 28 #include <asm/nmi.h>
 29 #include <asm/hw_irq.h>
 30 #include <asm/apic.h>
 31 #include <asm/io_apic.h>
 32 #include <asm/hpet.h>
 33 #include <linux/kdebug.h>
 34 #include <asm/cpu.h>
 35 #include <asm/reboot.h>
 36 #include <asm/virtext.h>
 37 
 38 /* Alignment required for elf header segment */
 39 #define ELF_CORE_HEADER_ALIGN   4096
 40 
 41 /* This primarily represents number of split ranges due to exclusion */
 42 #define CRASH_MAX_RANGES        16
 43 
 44 struct crash_mem_range {
 45         u64 start, end;
 46 };
 47 
 48 struct crash_mem {
 49         unsigned int nr_ranges;
 50         struct crash_mem_range ranges[CRASH_MAX_RANGES];
 51 };
 52 
 53 /* Misc data about ram ranges needed to prepare elf headers */
 54 struct crash_elf_data {
 55         struct kimage *image;
 56         /*
 57          * Total number of ram ranges we have after various adjustments for
 58          * GART, crash reserved region etc.
 59          */
 60         unsigned int max_nr_ranges;
 61         unsigned long gart_start, gart_end;
 62 
 63         /* Pointer to elf header */
 64         void *ehdr;
 65         /* Pointer to next phdr */
 66         void *bufp;
 67         struct crash_mem mem;
 68 };
 69 
 70 /* Used while preparing memory map entries for second kernel */
 71 struct crash_memmap_data {
 72         struct boot_params *params;
 73         /* Type of memory */
 74         unsigned int type;
 75 };
 76 
 77 int in_crash_kexec;
 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_vm(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         disable_local_APIC();
130 }
131 
132 static void kdump_nmi_shootdown_cpus(void)
133 {
134         in_crash_kexec = 1;
135         nmi_shootdown_cpus(kdump_nmi_callback);
136 
137         disable_local_APIC();
138 }
139 
140 #else
141 static void kdump_nmi_shootdown_cpus(void)
142 {
143         /* There are no cpus to shootdown */
144 }
145 #endif
146 
147 void native_machine_crash_shutdown(struct pt_regs *regs)
148 {
149         /* This function is only called after the system
150          * has panicked or is otherwise in a critical state.
151          * The minimum amount of code to allow a kexec'd kernel
152          * to run successfully needs to happen here.
153          *
154          * In practice this means shooting down the other cpus in
155          * an SMP system.
156          */
157         /* The kernel is broken so disable interrupts */
158         local_irq_disable();
159 
160         kdump_nmi_shootdown_cpus();
161 
162         /*
163          * VMCLEAR VMCSs loaded on this cpu if needed.
164          */
165         cpu_crash_vmclear_loaded_vmcss();
166 
167         /* Booting kdump kernel with VMX or SVM enabled won't work,
168          * because (among other limitations) we can't disable paging
169          * with the virt flags.
170          */
171         cpu_emergency_vmxoff();
172         cpu_emergency_svm_disable();
173 
174 #ifdef CONFIG_X86_IO_APIC
175         /* Prevent crash_kexec() from deadlocking on ioapic_lock. */
176         ioapic_zap_locks();
177         disable_IO_APIC();
178 #endif
179         lapic_shutdown();
180 #ifdef CONFIG_HPET_TIMER
181         hpet_disable();
182 #endif
183         crash_save_cpu(regs, safe_smp_processor_id());
184 }
185 
186 #ifdef CONFIG_KEXEC_FILE
187 static int get_nr_ram_ranges_callback(unsigned long start_pfn,
188                                 unsigned long nr_pfn, void *arg)
189 {
190         int *nr_ranges = arg;
191 
192         (*nr_ranges)++;
193         return 0;
194 }
195 
196 static int get_gart_ranges_callback(u64 start, u64 end, void *arg)
197 {
198         struct crash_elf_data *ced = arg;
199 
200         ced->gart_start = start;
201         ced->gart_end = end;
202 
203         /* Not expecting more than 1 gart aperture */
204         return 1;
205 }
206 
207 
208 /* Gather all the required information to prepare elf headers for ram regions */
209 static void fill_up_crash_elf_data(struct crash_elf_data *ced,
210                                    struct kimage *image)
211 {
212         unsigned int nr_ranges = 0;
213 
214         ced->image = image;
215 
216         walk_system_ram_range(0, -1, &nr_ranges,
217                                 get_nr_ram_ranges_callback);
218 
219         ced->max_nr_ranges = nr_ranges;
220 
221         /*
222          * We don't create ELF headers for GART aperture as an attempt
223          * to dump this memory in second kernel leads to hang/crash.
224          * If gart aperture is present, one needs to exclude that region
225          * and that could lead to need of extra phdr.
226          */
227         walk_iomem_res("GART", IORESOURCE_MEM, 0, -1,
228                                 ced, get_gart_ranges_callback);
229 
230         /*
231          * If we have gart region, excluding that could potentially split
232          * a memory range, resulting in extra header. Account for  that.
233          */
234         if (ced->gart_end)
235                 ced->max_nr_ranges++;
236 
237         /* Exclusion of crash region could split memory ranges */
238         ced->max_nr_ranges++;
239 
240         /* If crashk_low_res is not 0, another range split possible */
241         if (crashk_low_res.end)
242                 ced->max_nr_ranges++;
243 }
244 
245 static int exclude_mem_range(struct crash_mem *mem,
246                 unsigned long long mstart, unsigned long long mend)
247 {
248         int i, j;
249         unsigned long long start, end;
250         struct crash_mem_range temp_range = {0, 0};
251 
252         for (i = 0; i < mem->nr_ranges; i++) {
253                 start = mem->ranges[i].start;
254                 end = mem->ranges[i].end;
255 
256                 if (mstart > end || mend < start)
257                         continue;
258 
259                 /* Truncate any area outside of range */
260                 if (mstart < start)
261                         mstart = start;
262                 if (mend > end)
263                         mend = end;
264 
265                 /* Found completely overlapping range */
266                 if (mstart == start && mend == end) {
267                         mem->ranges[i].start = 0;
268                         mem->ranges[i].end = 0;
269                         if (i < mem->nr_ranges - 1) {
270                                 /* Shift rest of the ranges to left */
271                                 for (j = i; j < mem->nr_ranges - 1; j++) {
272                                         mem->ranges[j].start =
273                                                 mem->ranges[j+1].start;
274                                         mem->ranges[j].end =
275                                                         mem->ranges[j+1].end;
276                                 }
277                         }
278                         mem->nr_ranges--;
279                         return 0;
280                 }
281 
282                 if (mstart > start && mend < end) {
283                         /* Split original range */
284                         mem->ranges[i].end = mstart - 1;
285                         temp_range.start = mend + 1;
286                         temp_range.end = end;
287                 } else if (mstart != start)
288                         mem->ranges[i].end = mstart - 1;
289                 else
290                         mem->ranges[i].start = mend + 1;
291                 break;
292         }
293 
294         /* If a split happend, add the split to array */
295         if (!temp_range.end)
296                 return 0;
297 
298         /* Split happened */
299         if (i == CRASH_MAX_RANGES - 1) {
300                 pr_err("Too many crash ranges after split\n");
301                 return -ENOMEM;
302         }
303 
304         /* Location where new range should go */
305         j = i + 1;
306         if (j < mem->nr_ranges) {
307                 /* Move over all ranges one slot towards the end */
308                 for (i = mem->nr_ranges - 1; i >= j; i--)
309                         mem->ranges[i + 1] = mem->ranges[i];
310         }
311 
312         mem->ranges[j].start = temp_range.start;
313         mem->ranges[j].end = temp_range.end;
314         mem->nr_ranges++;
315         return 0;
316 }
317 
318 /*
319  * Look for any unwanted ranges between mstart, mend and remove them. This
320  * might lead to split and split ranges are put in ced->mem.ranges[] array
321  */
322 static int elf_header_exclude_ranges(struct crash_elf_data *ced,
323                 unsigned long long mstart, unsigned long long mend)
324 {
325         struct crash_mem *cmem = &ced->mem;
326         int ret = 0;
327 
328         memset(cmem->ranges, 0, sizeof(cmem->ranges));
329 
330         cmem->ranges[0].start = mstart;
331         cmem->ranges[0].end = mend;
332         cmem->nr_ranges = 1;
333 
334         /* Exclude crashkernel region */
335         ret = exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
336         if (ret)
337                 return ret;
338 
339         if (crashk_low_res.end) {
340                 ret = exclude_mem_range(cmem, crashk_low_res.start, crashk_low_res.end);
341                 if (ret)
342                         return ret;
343         }
344 
345         /* Exclude GART region */
346         if (ced->gart_end) {
347                 ret = exclude_mem_range(cmem, ced->gart_start, ced->gart_end);
348                 if (ret)
349                         return ret;
350         }
351 
352         return ret;
353 }
354 
355 static int prepare_elf64_ram_headers_callback(u64 start, u64 end, void *arg)
356 {
357         struct crash_elf_data *ced = arg;
358         Elf64_Ehdr *ehdr;
359         Elf64_Phdr *phdr;
360         unsigned long mstart, mend;
361         struct kimage *image = ced->image;
362         struct crash_mem *cmem;
363         int ret, i;
364 
365         ehdr = ced->ehdr;
366 
367         /* Exclude unwanted mem ranges */
368         ret = elf_header_exclude_ranges(ced, start, end);
369         if (ret)
370                 return ret;
371 
372         /* Go through all the ranges in ced->mem.ranges[] and prepare phdr */
373         cmem = &ced->mem;
374 
375         for (i = 0; i < cmem->nr_ranges; i++) {
376                 mstart = cmem->ranges[i].start;
377                 mend = cmem->ranges[i].end;
378 
379                 phdr = ced->bufp;
380                 ced->bufp += sizeof(Elf64_Phdr);
381 
382                 phdr->p_type = PT_LOAD;
383                 phdr->p_flags = PF_R|PF_W|PF_X;
384                 phdr->p_offset  = mstart;
385 
386                 /*
387                  * If a range matches backup region, adjust offset to backup
388                  * segment.
389                  */
390                 if (mstart == image->arch.backup_src_start &&
391                     (mend - mstart + 1) == image->arch.backup_src_sz)
392                         phdr->p_offset = image->arch.backup_load_addr;
393 
394                 phdr->p_paddr = mstart;
395                 phdr->p_vaddr = (unsigned long long) __va(mstart);
396                 phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
397                 phdr->p_align = 0;
398                 ehdr->e_phnum++;
399                 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",
400                         phdr, phdr->p_vaddr, phdr->p_paddr, phdr->p_filesz,
401                         ehdr->e_phnum, phdr->p_offset);
402         }
403 
404         return ret;
405 }
406 
407 static int prepare_elf64_headers(struct crash_elf_data *ced,
408                 void **addr, unsigned long *sz)
409 {
410         Elf64_Ehdr *ehdr;
411         Elf64_Phdr *phdr;
412         unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
413         unsigned char *buf, *bufp;
414         unsigned int cpu;
415         unsigned long long notes_addr;
416         int ret;
417 
418         /* extra phdr for vmcoreinfo elf note */
419         nr_phdr = nr_cpus + 1;
420         nr_phdr += ced->max_nr_ranges;
421 
422         /*
423          * kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
424          * area on x86_64 (ffffffff80000000 - ffffffffa0000000).
425          * I think this is required by tools like gdb. So same physical
426          * memory will be mapped in two elf headers. One will contain kernel
427          * text virtual addresses and other will have __va(physical) addresses.
428          */
429 
430         nr_phdr++;
431         elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
432         elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
433 
434         buf = vzalloc(elf_sz);
435         if (!buf)
436                 return -ENOMEM;
437 
438         bufp = buf;
439         ehdr = (Elf64_Ehdr *)bufp;
440         bufp += sizeof(Elf64_Ehdr);
441         memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
442         ehdr->e_ident[EI_CLASS] = ELFCLASS64;
443         ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
444         ehdr->e_ident[EI_VERSION] = EV_CURRENT;
445         ehdr->e_ident[EI_OSABI] = ELF_OSABI;
446         memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
447         ehdr->e_type = ET_CORE;
448         ehdr->e_machine = ELF_ARCH;
449         ehdr->e_version = EV_CURRENT;
450         ehdr->e_phoff = sizeof(Elf64_Ehdr);
451         ehdr->e_ehsize = sizeof(Elf64_Ehdr);
452         ehdr->e_phentsize = sizeof(Elf64_Phdr);
453 
454         /* Prepare one phdr of type PT_NOTE for each present cpu */
455         for_each_present_cpu(cpu) {
456                 phdr = (Elf64_Phdr *)bufp;
457                 bufp += sizeof(Elf64_Phdr);
458                 phdr->p_type = PT_NOTE;
459                 notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
460                 phdr->p_offset = phdr->p_paddr = notes_addr;
461                 phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
462                 (ehdr->e_phnum)++;
463         }
464 
465         /* Prepare one PT_NOTE header for vmcoreinfo */
466         phdr = (Elf64_Phdr *)bufp;
467         bufp += sizeof(Elf64_Phdr);
468         phdr->p_type = PT_NOTE;
469         phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
470         phdr->p_filesz = phdr->p_memsz = sizeof(vmcoreinfo_note);
471         (ehdr->e_phnum)++;
472 
473 #ifdef CONFIG_X86_64
474         /* Prepare PT_LOAD type program header for kernel text region */
475         phdr = (Elf64_Phdr *)bufp;
476         bufp += sizeof(Elf64_Phdr);
477         phdr->p_type = PT_LOAD;
478         phdr->p_flags = PF_R|PF_W|PF_X;
479         phdr->p_vaddr = (Elf64_Addr)_text;
480         phdr->p_filesz = phdr->p_memsz = _end - _text;
481         phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
482         (ehdr->e_phnum)++;
483 #endif
484 
485         /* Prepare PT_LOAD headers for system ram chunks. */
486         ced->ehdr = ehdr;
487         ced->bufp = bufp;
488         ret = walk_system_ram_res(0, -1, ced,
489                         prepare_elf64_ram_headers_callback);
490         if (ret < 0)
491                 return ret;
492 
493         *addr = buf;
494         *sz = elf_sz;
495         return 0;
496 }
497 
498 /* Prepare elf headers. Return addr and size */
499 static int prepare_elf_headers(struct kimage *image, void **addr,
500                                         unsigned long *sz)
501 {
502         struct crash_elf_data *ced;
503         int ret;
504 
505         ced = kzalloc(sizeof(*ced), GFP_KERNEL);
506         if (!ced)
507                 return -ENOMEM;
508 
509         fill_up_crash_elf_data(ced, image);
510 
511         /* By default prepare 64bit headers */
512         ret =  prepare_elf64_headers(ced, addr, sz);
513         kfree(ced);
514         return ret;
515 }
516 
517 static int add_e820_entry(struct boot_params *params, struct e820entry *entry)
518 {
519         unsigned int nr_e820_entries;
520 
521         nr_e820_entries = params->e820_entries;
522         if (nr_e820_entries >= E820MAX)
523                 return 1;
524 
525         memcpy(&params->e820_map[nr_e820_entries], entry,
526                         sizeof(struct e820entry));
527         params->e820_entries++;
528         return 0;
529 }
530 
531 static int memmap_entry_callback(u64 start, u64 end, void *arg)
532 {
533         struct crash_memmap_data *cmd = arg;
534         struct boot_params *params = cmd->params;
535         struct e820entry ei;
536 
537         ei.addr = start;
538         ei.size = end - start + 1;
539         ei.type = cmd->type;
540         add_e820_entry(params, &ei);
541 
542         return 0;
543 }
544 
545 static int memmap_exclude_ranges(struct kimage *image, struct crash_mem *cmem,
546                                  unsigned long long mstart,
547                                  unsigned long long mend)
548 {
549         unsigned long start, end;
550         int ret = 0;
551 
552         cmem->ranges[0].start = mstart;
553         cmem->ranges[0].end = mend;
554         cmem->nr_ranges = 1;
555 
556         /* Exclude Backup region */
557         start = image->arch.backup_load_addr;
558         end = start + image->arch.backup_src_sz - 1;
559         ret = exclude_mem_range(cmem, start, end);
560         if (ret)
561                 return ret;
562 
563         /* Exclude elf header region */
564         start = image->arch.elf_load_addr;
565         end = start + image->arch.elf_headers_sz - 1;
566         return exclude_mem_range(cmem, start, end);
567 }
568 
569 /* Prepare memory map for crash dump kernel */
570 int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params)
571 {
572         int i, ret = 0;
573         unsigned long flags;
574         struct e820entry ei;
575         struct crash_memmap_data cmd;
576         struct crash_mem *cmem;
577 
578         cmem = vzalloc(sizeof(struct crash_mem));
579         if (!cmem)
580                 return -ENOMEM;
581 
582         memset(&cmd, 0, sizeof(struct crash_memmap_data));
583         cmd.params = params;
584 
585         /* Add first 640K segment */
586         ei.addr = image->arch.backup_src_start;
587         ei.size = image->arch.backup_src_sz;
588         ei.type = E820_RAM;
589         add_e820_entry(params, &ei);
590 
591         /* Add ACPI tables */
592         cmd.type = E820_ACPI;
593         flags = IORESOURCE_MEM | IORESOURCE_BUSY;
594         walk_iomem_res("ACPI Tables", flags, 0, -1, &cmd,
595                        memmap_entry_callback);
596 
597         /* Add ACPI Non-volatile Storage */
598         cmd.type = E820_NVS;
599         walk_iomem_res("ACPI Non-volatile Storage", flags, 0, -1, &cmd,
600                         memmap_entry_callback);
601 
602         /* Add crashk_low_res region */
603         if (crashk_low_res.end) {
604                 ei.addr = crashk_low_res.start;
605                 ei.size = crashk_low_res.end - crashk_low_res.start + 1;
606                 ei.type = E820_RAM;
607                 add_e820_entry(params, &ei);
608         }
609 
610         /* Exclude some ranges from crashk_res and add rest to memmap */
611         ret = memmap_exclude_ranges(image, cmem, crashk_res.start,
612                                                 crashk_res.end);
613         if (ret)
614                 goto out;
615 
616         for (i = 0; i < cmem->nr_ranges; i++) {
617                 ei.size = cmem->ranges[i].end - cmem->ranges[i].start + 1;
618 
619                 /* If entry is less than a page, skip it */
620                 if (ei.size < PAGE_SIZE)
621                         continue;
622                 ei.addr = cmem->ranges[i].start;
623                 ei.type = E820_RAM;
624                 add_e820_entry(params, &ei);
625         }
626 
627 out:
628         vfree(cmem);
629         return ret;
630 }
631 
632 static int determine_backup_region(u64 start, u64 end, void *arg)
633 {
634         struct kimage *image = arg;
635 
636         image->arch.backup_src_start = start;
637         image->arch.backup_src_sz = end - start + 1;
638 
639         /* Expecting only one range for backup region */
640         return 1;
641 }
642 
643 int crash_load_segments(struct kimage *image)
644 {
645         unsigned long src_start, src_sz, elf_sz;
646         void *elf_addr;
647         int ret;
648 
649         /*
650          * Determine and load a segment for backup area. First 640K RAM
651          * region is backup source
652          */
653 
654         ret = walk_system_ram_res(KEXEC_BACKUP_SRC_START, KEXEC_BACKUP_SRC_END,
655                                 image, determine_backup_region);
656 
657         /* Zero or postive return values are ok */
658         if (ret < 0)
659                 return ret;
660 
661         src_start = image->arch.backup_src_start;
662         src_sz = image->arch.backup_src_sz;
663 
664         /* Add backup segment. */
665         if (src_sz) {
666                 /*
667                  * Ideally there is no source for backup segment. This is
668                  * copied in purgatory after crash. Just add a zero filled
669                  * segment for now to make sure checksum logic works fine.
670                  */
671                 ret = kexec_add_buffer(image, (char *)&crash_zero_bytes,
672                                        sizeof(crash_zero_bytes), src_sz,
673                                        PAGE_SIZE, 0, -1, 0,
674                                        &image->arch.backup_load_addr);
675                 if (ret)
676                         return ret;
677                 pr_debug("Loaded backup region at 0x%lx backup_start=0x%lx memsz=0x%lx\n",
678                          image->arch.backup_load_addr, src_start, src_sz);
679         }
680 
681         /* Prepare elf headers and add a segment */
682         ret = prepare_elf_headers(image, &elf_addr, &elf_sz);
683         if (ret)
684                 return ret;
685 
686         image->arch.elf_headers = elf_addr;
687         image->arch.elf_headers_sz = elf_sz;
688 
689         ret = kexec_add_buffer(image, (char *)elf_addr, elf_sz, elf_sz,
690                         ELF_CORE_HEADER_ALIGN, 0, -1, 0,
691                         &image->arch.elf_load_addr);
692         if (ret) {
693                 vfree((void *)image->arch.elf_headers);
694                 return ret;
695         }
696         pr_debug("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
697                  image->arch.elf_load_addr, elf_sz, elf_sz);
698 
699         return ret;
700 }
701 #endif /* CONFIG_KEXEC_FILE */
702 

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