NAME

       ksplice-create - Create a set of kernel modules for a rebootless kernel update

SYNOPSIS

       ksplice-create [OPTIONS] --patch=PATCH_FILE KERNEL_SOURCE

       ksplice-create [OPTIONS] --diffext=EXTENSION KERNEL_SOURCE

       ksplice-create [OPTIONS] --git=COMMIT KERNEL_SOURCE

       ksplice-create [OPTIONS] --prebuild KERNEL_SOURCE

DESCRIPTION

       ksplice-create creates a set of Ksplice kernel modules that, when loaded, will apply a
       user-specified source code patch to the running binary kernel.

       Before you use ksplice-create on a patch, you should confirm that the desired source code
       change does not make any semantic changes to kernel data structures--that is, changes that
       would require existing instances of kernel data structures to be transformed (e.g., a
       patch that adds a field to a global data structure would require the existing data
       structures to change).  If you use Ksplice on a patch that changes data structure
       semantics, Ksplice will not detect the problem and you could experience kernel problems as
       a result.

       The to-be-applied source code patch can be specified by providing a patch(1) file
       (--patch=PATCH_FILE) or by providing a file extension (--diffext=EXTENSION).

       If a file extension is specified, then the desired source code patch will be determined by
       comparing all of the files in the KERNEL_SOURCE directory tree whose names end with the
       extra extension EXTENSION against the corresponding files without the extra extension.
       Only the new files containing the extra extension in their filenames should be modified.

       Here is an example of using a file extension to specify a patch:

        $ cp KERNEL_SOURCE/kernel/sys.c KERNEL_SOURCE/kernel/sys.c.prctl_fixed
        [edit sys.c.prctl_fixed to include the desired changes]
        $ ksplice-create --diffext=.prctl_fixed KERNEL_SOURCE

       KERNEL_SOURCE must be a directory containing the to-be-updated kernel's original source
       code.  If your Linux distribution applies patches to the Linux kernel during the kernel
       build process, then those patches must be applied to the KERNEL_SOURCE directory before
       invoking ksplice-create on that directory.  ksplice-create will not modify the source code
       in the KERNEL_SOURCE directory tree, but it will perform a kernel build in that directory
       tree.

       ORIG_CONFIG can be used to specify the directory containing the to-be-updated kernel's
       original .config file and original System.map file (the files should have exactly those
       names).  ORIG_CONFIG defaults to KERNEL_SOURCE/ksplice.

       The default gcc(1) compiler and as(1) assembler on the system should be as close to the
       compiler and assembler originally used to build the running kernel as possible.  If the
       current compiler and linker are too different from the original compiler and linker,
       ksplice-apply will abort when applying the update.

       ksplice-create outputs a tar(1) file, compressed with gzip(1), containing the desired
       Ksplice update modules.  This tarball will be created in the current directory, and it can
       be manipulated using the other Ksplice utilities, such as ksplice-apply.

       The first time that ksplice-create is invoked on a KERNEL_SOURCE directory, it must build
       that kernel from scratch, which is much slower than the rest of the update-creation
       process.  --prebuild can be used to perform this initial kernel build without providing a
       source code patch.

       In order to patch a function that has previously been patched by Ksplice, the user needs
       to ensure that the KERNEL_SOURCE directory provided to Ksplice contains the source for the
       currently running kernel, including any patches that have previously been applied by
       Ksplice.

OPTIONS

       --patch=PATCH_FILE
               Builds a Ksplice update out of the given patch(1) file PATCH_FILE.

       --diffext=EXTENSION
               Builds a Ksplice update using the modified source files with names ending in
               EXTENSION.  The patch will be determined by comparing all of the files in the
               KERNEL_SOURCE directory tree whose names end with the extra extension EXTENSION
               against the corresponding files without the extra extension.

       --git=COMMIT
               Builds a Ksplice update using the commit COMMIT in the Git working tree
               KERNEL_SOURCE.  The original state corresponding to the running kernel is
               remembered in the Git ref refs/ksplice/pre, which will be created from the current
               HEAD if it does not yet exist (and can be changed using the --series option).
               Therefore, the source code change to be applied corresponds to the output of git
               diff ksplice/pre COMMIT.

       --prebuild
               Compiles the original source code that will be needed to build future Ksplice
               updates.  If any Ksplice updates have previously been built in the KERNEL_SOURCE
               tree, the source files in the tree are reverted to their original state.

       --series
               Specifies that the current state of the KERNEL_SOURCE tree should be used as the
               original source that corresponds to the running kernel.  If a Ksplice update has
               recently been built in the KERNEL_SOURCE tree, this option specifies that the
               Ksplice update being built should be applied after the previous update in series.
               This option can be used with --prebuild to forget the previous original state and
               perform no other action.

       --build-modules
               For a patch that includes changes to kernel modules, in addition to building a hot
               update that can be applied to the running kernel, this option will cause ksplice-
               create to generate a set of new modules based on the updated source code.  These
               modules can be used to replace the kernel modules stored on disk, where they can
               later be loaded normally after part of the hot update has been applied using
               ksplice-apply(1) --partial.

       -v, --verbose
               Causes ksplice-create to print debugging messages about its progress.  Using
               multiple -v options increases the verbosity.  The maximum is 2.

       -j JOBS, --jobs=JOBS
               Specifies the number of jobs to run simultaneously while performing kernel builds.
               ksplice-create also honors the environment variable CONCURRENCY_LEVEL.

       --patch-opt=OPTIONS
               Can be used to pass options to patch(1).  If this option is NOT specified, then
               -p1 is passed to patch.  If this option is specified, then only the specified
               options will be passed to patch.  This option can be repeated in order to pass
               multiple options to patch.  This option is ignored when the to-be-applied source
               code patch is specified using --diffext.

       --id=ID Specifies the unique value that will be used as the identifier of the Ksplice
               update.  This identifier will, for example, appear in the name of the update
               tarball.  By default, a random 8-character ID will be generated.

SEE ALSO

       ksplice-apply(8), ksplice-view(8), ksplice-undo(8)

BUGS

       Please report bugs to <devel@ksplice.com>.

AUTHORS

       Jeff Arnold, Anders Kaseorg, and Tim Abbott

COPYRIGHT

       Copyright (C) 2007-2009  Ksplice, Inc.

       This is free software and documentation.  You can redistribute and/or modify it under the
       terms of the GNU General Public License, version 2.