1*2c44b67eSBaoquan He // SPDX-License-Identifier: GPL-2.0-only 2*2c44b67eSBaoquan He #include <linux/kernel.h> 3*2c44b67eSBaoquan He #include <linux/crash_dump.h> 4*2c44b67eSBaoquan He #include <linux/init.h> 5*2c44b67eSBaoquan He #include <linux/errno.h> 6*2c44b67eSBaoquan He #include <linux/export.h> 7*2c44b67eSBaoquan He 8*2c44b67eSBaoquan He /* 9*2c44b67eSBaoquan He * stores the physical address of elf header of crash image 10*2c44b67eSBaoquan He * 11*2c44b67eSBaoquan He * Note: elfcorehdr_addr is not just limited to vmcore. It is also used by 12*2c44b67eSBaoquan He * is_kdump_kernel() to determine if we are booting after a panic. Hence put 13*2c44b67eSBaoquan He * it under CONFIG_CRASH_DUMP and not CONFIG_PROC_VMCORE. 14*2c44b67eSBaoquan He */ 15*2c44b67eSBaoquan He unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX; 16*2c44b67eSBaoquan He EXPORT_SYMBOL_GPL(elfcorehdr_addr); 17*2c44b67eSBaoquan He 18*2c44b67eSBaoquan He /* 19*2c44b67eSBaoquan He * stores the size of elf header of crash image 20*2c44b67eSBaoquan He */ 21*2c44b67eSBaoquan He unsigned long long elfcorehdr_size; 22*2c44b67eSBaoquan He 23*2c44b67eSBaoquan He /* 24*2c44b67eSBaoquan He * elfcorehdr= specifies the location of elf core header stored by the crashed 25*2c44b67eSBaoquan He * kernel. This option will be passed by kexec loader to the capture kernel. 26*2c44b67eSBaoquan He * 27*2c44b67eSBaoquan He * Syntax: elfcorehdr=[size[KMG]@]offset[KMG] 28*2c44b67eSBaoquan He */ 29*2c44b67eSBaoquan He static int __init setup_elfcorehdr(char *arg) 30*2c44b67eSBaoquan He { 31*2c44b67eSBaoquan He char *end; 32*2c44b67eSBaoquan He if (!arg) 33*2c44b67eSBaoquan He return -EINVAL; 34*2c44b67eSBaoquan He elfcorehdr_addr = memparse(arg, &end); 35*2c44b67eSBaoquan He if (*end == '@') { 36*2c44b67eSBaoquan He elfcorehdr_size = elfcorehdr_addr; 37*2c44b67eSBaoquan He elfcorehdr_addr = memparse(end + 1, &end); 38*2c44b67eSBaoquan He } 39*2c44b67eSBaoquan He return end > arg ? 0 : -EINVAL; 40*2c44b67eSBaoquan He } 41*2c44b67eSBaoquan He early_param("elfcorehdr", setup_elfcorehdr); 42