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/.

Linux                                              2012-07-13                                      KEXEC_LOAD(2)