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author | Joe Lawrence <joe.lawrence@redhat.com> | 2017-10-13 15:08:41 -0400 |
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committer | Jiri Kosina <jkosina@suse.cz> | 2017-10-19 10:08:56 +0200 |
commit | 93862e385ded7c60351e09fcd2a541d273650905 (patch) | |
tree | 22dc512303e988d00e327fa05c884e542fb5af55 /samples/livepatch/livepatch-callbacks-mod.c | |
parent | 19205da6a0da701787d42ad754edd1ffb514c956 (diff) | |
download | op-kernel-dev-93862e385ded7c60351e09fcd2a541d273650905.zip op-kernel-dev-93862e385ded7c60351e09fcd2a541d273650905.tar.gz |
livepatch: add (un)patch callbacks
Provide livepatch modules a klp_object (un)patching notification
mechanism. Pre and post-(un)patch callbacks allow livepatch modules to
setup or synchronize changes that would be difficult to support in only
patched-or-unpatched code contexts.
Callbacks can be registered for target module or vmlinux klp_objects,
but each implementation is klp_object specific.
- Pre-(un)patch callbacks run before any (un)patching transition
starts.
- Post-(un)patch callbacks run once an object has been (un)patched and
the klp_patch fully transitioned to its target state.
Example use cases include modification of global data and registration
of newly available services/handlers.
See Documentation/livepatch/callbacks.txt for details and
samples/livepatch/ for examples.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'samples/livepatch/livepatch-callbacks-mod.c')
-rw-r--r-- | samples/livepatch/livepatch-callbacks-mod.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/samples/livepatch/livepatch-callbacks-mod.c b/samples/livepatch/livepatch-callbacks-mod.c new file mode 100644 index 0000000..e610ce2 --- /dev/null +++ b/samples/livepatch/livepatch-callbacks-mod.c @@ -0,0 +1,53 @@ +/* + * Copyright (C) 2017 Joe Lawrence <joe.lawrence@redhat.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +/* + * livepatch-callbacks-mod.c - (un)patching callbacks demo support module + * + * + * Purpose + * ------- + * + * Simple module to demonstrate livepatch (un)patching callbacks. + * + * + * Usage + * ----- + * + * This module is not intended to be standalone. See the "Usage" + * section of livepatch-callbacks-demo.c. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> + +static int livepatch_callbacks_mod_init(void) +{ + pr_info("%s\n", __func__); + return 0; +} + +static void livepatch_callbacks_mod_exit(void) +{ + pr_info("%s\n", __func__); +} + +module_init(livepatch_callbacks_mod_init); +module_exit(livepatch_callbacks_mod_exit); +MODULE_LICENSE("GPL"); |