801295be01
Use nolibc include directory rather than include a cumulative nolibc.h on the compiler command line and replace use of 'sudo cpio' with usr/gen_init_cpio. While on it fix spelling of KHO_FINALIZE Link: https://lkml.kernel.org/r/20250811082510.4154080-4-rppt@kernel.org Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Suggested-by: Thomas Weißschuh <linux@weissschuh.net> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Pratyush Yadav <pratyush@kernel.org> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
96 lines
1.7 KiB
C
96 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <stdio.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <sys/syscall.h>
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#include <sys/mount.h>
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#include <sys/reboot.h>
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#include <linux/kexec.h>
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/* from arch/x86/include/asm/setup.h */
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#define COMMAND_LINE_SIZE 2048
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#define KHO_FINALIZE "/debugfs/kho/out/finalize"
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#define KERNEL_IMAGE "/kernel"
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static int mount_filesystems(void)
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{
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if (mount("debugfs", "/debugfs", "debugfs", 0, NULL) < 0)
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return -1;
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return mount("proc", "/proc", "proc", 0, NULL);
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}
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static int kho_enable(void)
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{
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const char enable[] = "1";
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int fd;
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fd = open(KHO_FINALIZE, O_RDWR);
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if (fd < 0)
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return -1;
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if (write(fd, enable, sizeof(enable)) != sizeof(enable))
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return 1;
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close(fd);
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return 0;
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}
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static long kexec_file_load(int kernel_fd, int initrd_fd,
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unsigned long cmdline_len, const char *cmdline,
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unsigned long flags)
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{
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return syscall(__NR_kexec_file_load, kernel_fd, initrd_fd, cmdline_len,
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cmdline, flags);
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}
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static int kexec_load(void)
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{
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char cmdline[COMMAND_LINE_SIZE];
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ssize_t len;
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int fd, err;
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fd = open("/proc/cmdline", O_RDONLY);
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if (fd < 0)
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return -1;
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len = read(fd, cmdline, sizeof(cmdline));
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close(fd);
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if (len < 0)
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return -1;
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/* replace \n with \0 */
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cmdline[len - 1] = 0;
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fd = open(KERNEL_IMAGE, O_RDONLY);
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if (fd < 0)
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return -1;
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err = kexec_file_load(fd, -1, len, cmdline, KEXEC_FILE_NO_INITRAMFS);
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close(fd);
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return err ? : 0;
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}
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int main(int argc, char *argv[])
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{
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if (mount_filesystems())
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goto err_reboot;
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if (kho_enable())
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goto err_reboot;
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if (kexec_load())
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goto err_reboot;
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if (reboot(RB_KEXEC))
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goto err_reboot;
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return 0;
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err_reboot:
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reboot(RB_AUTOBOOT);
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return -1;
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}
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