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#include <unistd.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <linux/kexec.h>
#include <linux/reboot.h>
#include <sys/reboot.h>
#include <sys/syscall.h>
asm(
" .code64\n"
" .data\n"
"purgatory_start:\n"
// Trigger kexec debug exception handling
" int3\n"
// Set load address for next time
" leaq purgatory_start_b(%rip), %r11\n"
" movq %r11, 8(%rsp)\n"
// Back to Linux
" ret\n"
// Same again
"purgatory_start_b:\n"
// Trigger kexec debug exception handling
" int3\n"
// Set load address for next time
" leaq purgatory_start(%rip), %r11\n"
" movq %r11, 8(%rsp)\n"
// Back to Linux
" ret\n"
"purgatory_end:\n"
".previous"
);
extern char purgatory_start[], purgatory_end[];
int main (void)
{
struct kexec_segment segment = {};
int ret;
segment.buf = purgatory_start;
segment.bufsz = purgatory_end - purgatory_start;
segment.mem = (void *)0x400000;
segment.memsz = 0x1000;
ret = syscall(__NR_kexec_load, 0x400000, 1, &segment, KEXEC_PRESERVE_CONTEXT);
if (ret) {
perror("kexec_load");
exit(1);
}
ret = syscall(__NR_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_KEXEC);
if (ret) {
perror("kexec reboot");
exit(1);
}
ret = syscall(__NR_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_KEXEC);
if (ret) {
perror("kexec reboot");
exit(1);
}
printf("Success\n");
return 0;
}
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