1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/kernel.h>
3#include <linux/crash_dump.h>
4#include <linux/init.h>
5#include <linux/errno.h>
6#include <linux/export.h>
7
8/*
9 * stores the physical address of elf header of crash image
10 *
11 * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by
12 * is_kdump_kernel() to determine if we are booting after a panic. Hence put
13 * it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE.
14 */
15unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX;
16EXPORT_SYMBOL_GPL(elfcorehdr_addr);
17
18/*
19 * stores the size of elf header of crash image
20 */
21unsigned long long elfcorehdr_size;
22
23/*
24 * elfcorehdr= specifies the location of elf core header stored by the crashed
25 * kernel. This option will be passed by kexec loader to the capture kernel.
26 *
27 * Syntax: elfcorehdr=[size[KMG]@]offset[KMG]
28 */
29static int __init setup_elfcorehdr(char *arg)
30{
31 char *end;
32 if (!arg)
33 return -EINVAL;
34 elfcorehdr_addr = memparse(ptr: arg, retptr: &end);
35 if (*end == '@') {
36 elfcorehdr_size = elfcorehdr_addr;
37 elfcorehdr_addr = memparse(ptr: end + 1, retptr: &end);
38 }
39 return end > arg ? 0 : -EINVAL;
40}
41early_param("elfcorehdr", setup_elfcorehdr);
42

source code of linux/kernel/crash_dump.c