KEXECLOAD(2) Linux Programmer's Manual KEXECLOAD(2)

NAME
       kexecload - load a new kernel for later execution

SYNOPSIS
       #include 
       long kexecload(unsigned long entry, unsigned long nrsegments,
                       struct kexecsegment *segments, unsigned long flags);

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

DESCRIPTION
       The  kexecload()  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  opera‐
       tion of the call.  The following values can be specified in flags:

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

       KEXECPRESERVECONTEXT (since Linux 2.6.27)
              Preserve  the system hardware and software states before execut‐
              ing the new kernel.  This could  be  used  for  system  suspend.
              This  flag  is  available only if the kernel was configured with
              CONFIGKEXECJUMP, and  is  effective  only  if  nrsegments  is
              greater than 0.

       The  low-order bits of flags contain the architecture of the to-be-exe‐
       cuted kernel.  Specify (OR) the constant KEXECARCHDEFAULT to use  the
       current  architecture,  or  one of the following architecture constants
       KEXECARCH386,  KEXECARCHX8664,  KEXECARCHPPC,  KEXECARCHPPC64,
       KEXECARCHIA64,   KEXECARCHARM,   KEXECARCHS390,   KEXECARCHSH,
       KEXECARCHMIPS, and KEXECARCHMIPSLE.  The architecture must be exe‐
       cutable on the CPU of the system.

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

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

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

RETURN VALUE
       On success, kexecload() 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 nrsegments is too large

       EPERM  The caller does not have the CAPSYSBOOT capability.

VERSIONS
       The kexecload() 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 kexecload().  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
       CONFIGKEXEC.

SEE ALSO
       reboot(2), syscall(2)

COLOPHON
       This  page  is  part of release 3.53 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                     KEXECLOAD(2)