NAME

       kexec_load - load a new kernel for later execution

SYNOPSIS

       #include <linux/kexec.h>
       long kexec_load(unsigned long entry, unsigned long nr_segments,
                       struct kexec_segment *segments, unsigned long flags);

       Note: There is no glibc wrapper for this system call; see NOTES.

DESCRIPTION

       The kexec_load() system call loads a new kernel that can be executed later by reboot(2).

       The flags argument is a mask whose high-order bits control the operation of the call.  The
       following values can be specified in flags:

       KEXEC_ON_CRASH (since Linux 2.6.13)
              Execute the new kernel automatically on a system crash.

       KEXEC_PRESERVE_CONTEXT (since Linux 2.6.27)
              Preserve the system hardware and software states before executing the  new  kernel.
              This  could  be used for system suspend.  This flag is available only if the kernel
              was configured with CONFIG_KEXEC_JUMP, and is  effective  only  if  nr_segments  is
              greater than 0.

       The  low-order  bits  of  flags  contain  the  architecture  of the to-be-executed kernel.
       Specify (OR) the constant KEXEC_ARCH_DEFAULT to use the current architecture,  or  one  of
       the  following  architecture  constants KEXEC_ARCH_386, KEXEC_ARCH_X86_64, KEXEC_ARCH_PPC,
       KEXEC_ARCH_PPC64,  KEXEC_ARCH_IA_64,   KEXEC_ARCH_ARM,   KEXEC_ARCH_S390,   KEXEC_ARCH_SH,
       KEXEC_ARCH_MIPS,  and  KEXEC_ARCH_MIPS_LE.  The architecture must be executable on the CPU
       of the system.

       The entry argument is the physical entry address in the  kernel  image.   The  nr_segments
       argument  is  the  number  of  segments  pointed to by the segments pointer.  The segments
       argument is an array of kexec_segment structures which define the kernel layout:

           struct kexec_segment {
               void   *buf;        /* Buffer in user space */
               size_t  bufsz;      /* Buffer length in user space */
               void   *mem;        /* Physical address of kernel */
               size_t  memsz;      /* Physical address length */
           };

       The kernel image defined by segments is copied from the calling  process  into  previously
       reserved memory.

RETURN VALUE

       On success, kexec_load() returns 0.  On error, -1 is returned and errno is set to indicate
       the error.

ERRORS

       EBUSY  Another crash kernel is already being loaded or a crash kernel is already in use.

       EINVAL flags is invalid; or nr_segments is too large

       EPERM  The caller does not have the CAP_SYS_BOOT capability.

VERSIONS

       The kexec_load() system call first appeared in Linux 2.6.13.

CONFORMING TO

       This system call is Linux-specific.

NOTES

       Currently, there is no glibc support for kexec_load().  Call it using syscall(2).

       The required constants are in the Linux kernel source file  linux/kexec.h,  which  is  not
       currently exported to glibc.  Therefore, these constants must be defined manually.

       This system call is available only if the kernel was configured with CONFIG_KEXEC.

SEE ALSO

       reboot(2), syscall(2)

COLOPHON

       This  page  is  part of release 3.54 of the Linux man-pages project.  A description of the
       project,    and    information    about    reporting    bugs,    can    be    found     at
       http://www.kernel.org/doc/man-pages/.