samples/livepatch/livepatch-callbacks-demo.c

1 // SPDX-License-Identifier: GPL-2.0-or-later
7  * livepatch-callbacks-demo.c - (un)patching callbacks livepatch demo
11  * -------
17  * -----
19  * Step 1 - load the simple module
21  *   insmod samples/livepatch/livepatch-callbacks-mod.ko
24  * Step 2 - load the demonstration livepatch (with callbacks)
26  *   insmod samples/livepatch/livepatch-callbacks-demo.ko
29  * Step 3 - cleanup
38  * NOTE: swap the insmod order of livepatch-callbacks-mod.ko and
39  *       livepatch-callbacks-demo.ko to observe what happens when a
42  * NOTE: 'pre_patch_ret' is a module parameter that sets the pre-patch
43  *       callback return status.  Try setting up a non-zero status
44  *       such as -19 (-ENODEV):
47  *       insmod samples/livepatch/livepatch-callbacks-demo.ko
49  *       # Setup next pre-patch callback to return -ENODEV
50  *       echo -19 > /sys/module/livepatch_callbacks_demo/parameters/pre_patch_ret
53  *       insmod samples/livepatch/livepatch-callbacks-mod.ko
54 …*       insmod: ERROR: could not insert module samples/livepatch/livepatch-callbacks-mod.ko: No su…
57  *       livepatch-callbacks-busymod.ko, available for experimenting
66  *       insmod samples/livepatch/livepatch-callbacks-busymod.ko sleep_secs=30
69  *       insmod samples/livepatch/livepatch-callbacks-demo.ko
73  *       insmod samples/livepatch/livepatch-callbacks-mod.ko
74  *       rmmod samples/livepatch/livepatch-callbacks-mod.ko
78  *       rmmod samples/livepatch/livepatch-callbacks-demo.ko
95 	[MODULE_STATE_UNFORMED]	= "[MODULE_STATE_UNFORMED] Still setting it up",
100 	if (obj->mod)  in callback_info()
101 		pr_info("%s: %s -> %s\n", callback, obj->mod->name,  in callback_info()
102 			module_state[obj->mod->state]);  in callback_info()