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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
| commit | cf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch) | |
| tree | 757a3d280760c654767631cab5ad8af2d86d1848 /samples/livepatch/livepatch-callbacks-demo.c | |
| download | linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip | |
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij:
"Core changes:
- Use the non-blocking mux_state_try_select() in the generic MUX pin
control back-end
- Free pin maps on pinctrl_generic_to_map() failure in the core
helpers
New hardware pin control:
- Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC
(this is for the low power audio, LPASS = Low Power Audio SubSystem
portions)
- Upboard support on top of the Intel pin controller
- Apple T6030 and T6031 support (just compatible strings)
- Samsung Exynos 8855 SoC
- Mediatek MT6858 SoC
- Rockchip RK3308B and RV1106 SoCs
- Airoha EN7523 and AN7563 SoCs
Improvements:
- Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable
- Qualcomm improvements on top of the Qualcomm PDC (power domain
controller) irqchip improvements from tglx:s tree
- Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups
- The NPCM8xx driver has been put into shape fixing many pin and
group definitions
- Some non-urgent Tegra 264 pin assignments are fixed up
- Some non-urgent fixups to Airoha AN7581 and AN7583 registers and
pin assignments, missing features etc"
* tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits)
dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema
pinctrl: meson: sync some modify from A4
pinctrl: meson: a4: Add input enable pin configuration
pinctrl: realtek: rtd1625: remove unused group name spdif_sel
pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13
dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema
Revert "Merge branch 'ib-rsk7204' into devel"
pinctrl: rockchip: Add RV1106 pinctrl support
dt-bindings: pinctrl: rockchip: Add RV1106 compatible
pinctrl: rockchip: Decode drive strength in the get function
pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable
pinctrl: airoha: add support of an7563 SoC
dt-bindings: pinctrl: airoha: add support of an7563 pin controller
pinctrl: airoha: try to find chip scu node by phandle first
pinctrl: airoha: add support of en7523 SoC
dt-bindings: pinctrl: airoha: add support of en7523 pin controller
pinctrl: airoha: an7583: add support for olt pinmux
pinctrl: airoha: an7583: add support for pon_alt pinmux
pinctrl: airoha: an7583: add support for npu_uart pinmux
dt-bindings: pinctrl: airoha: an7583: add missed features
...
Diffstat (limited to 'samples/livepatch/livepatch-callbacks-demo.c')
| -rw-r--r-- | samples/livepatch/livepatch-callbacks-demo.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/samples/livepatch/livepatch-callbacks-demo.c b/samples/livepatch/livepatch-callbacks-demo.c new file mode 100644 index 000000000..9e69d9cae --- /dev/null +++ b/samples/livepatch/livepatch-callbacks-demo.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2017 Joe Lawrence <joe.lawrence@redhat.com> + */ + +/* + * livepatch-callbacks-demo.c - (un)patching callbacks livepatch demo + * + * + * Purpose + * ------- + * + * Demonstration of registering livepatch (un)patching callbacks. + * + * + * Usage + * ----- + * + * Step 1 - load the simple module + * + * insmod samples/livepatch/livepatch-callbacks-mod.ko + * + * + * Step 2 - load the demonstration livepatch (with callbacks) + * + * insmod samples/livepatch/livepatch-callbacks-demo.ko + * + * + * Step 3 - cleanup + * + * echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled + * rmmod livepatch_callbacks_demo + * rmmod livepatch_callbacks_mod + * + * Watch dmesg output to see livepatch enablement, callback execution + * and patching operations for both vmlinux and module targets. + * + * NOTE: swap the insmod order of livepatch-callbacks-mod.ko and + * livepatch-callbacks-demo.ko to observe what happens when a + * target module is loaded after a livepatch with callbacks. + * + * NOTE: 'pre_patch_ret' is a module parameter that sets the pre-patch + * callback return status. Try setting up a non-zero status + * such as -19 (-ENODEV): + * + * # Load demo livepatch, vmlinux is patched + * insmod samples/livepatch/livepatch-callbacks-demo.ko + * + * # Setup next pre-patch callback to return -ENODEV + * echo -19 > /sys/module/livepatch_callbacks_demo/parameters/pre_patch_ret + * + * # Module loader refuses to load the target module + * insmod samples/livepatch/livepatch-callbacks-mod.ko + * insmod: ERROR: could not insert module samples/livepatch/livepatch-callbacks-mod.ko: No such device + * + * NOTE: There is a second target module, + * livepatch-callbacks-busymod.ko, available for experimenting + * with livepatch (un)patch callbacks. This module contains + * a 'sleep_secs' parameter that parks the module on one of the + * functions that the livepatch demo module wants to patch. + * Modifying this value and tweaking the order of module loads can + * effectively demonstrate stalled patch transitions: + * + * # Load a target module, let it park on 'busymod_work_func' for + * # thirty seconds + * insmod samples/livepatch/livepatch-callbacks-busymod.ko sleep_secs=30 + * + * # Meanwhile load the livepatch + * insmod samples/livepatch/livepatch-callbacks-demo.ko + * + * # ... then load and unload another target module while the + * # transition is in progress + * insmod samples/livepatch/livepatch-callbacks-mod.ko + * rmmod samples/livepatch/livepatch-callbacks-mod.ko + * + * # Finally cleanup + * echo 0 > /sys/kernel/livepatch/livepatch_callbacks_demo/enabled + * rmmod samples/livepatch/livepatch-callbacks-demo.ko + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/livepatch.h> + +static int pre_patch_ret; +module_param(pre_patch_ret, int, 0644); +MODULE_PARM_DESC(pre_patch_ret, "pre_patch_ret (default=0)"); + +static const char *const module_state[] = { + [MODULE_STATE_LIVE] = "[MODULE_STATE_LIVE] Normal state", + [MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init", + [MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away", + [MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up", +}; + +static void callback_info(const char *callback, struct klp_object *obj) +{ + if (obj->mod) + pr_info("%s: %s -> %s\n", callback, obj->mod->name, + module_state[obj->mod->state]); + else + pr_info("%s: vmlinux\n", callback); +} + +/* Executed on object patching (ie, patch enablement) */ +static int pre_patch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); + return pre_patch_ret; +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void post_patch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void pre_unpatch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +/* Executed on object unpatching (ie, patch disablement) */ +static void post_unpatch_callback(struct klp_object *obj) +{ + callback_info(__func__, obj); +} + +static void patched_work_func(struct work_struct *work) +{ + pr_info("%s\n", __func__); +} + +static struct klp_func no_funcs[] = { + { } +}; + +static struct klp_func busymod_funcs[] = { + { + .old_name = "busymod_work_func", + .new_func = patched_work_func, + }, { } +}; + +static struct klp_object objs[] = { + { + .name = NULL, /* vmlinux */ + .funcs = no_funcs, + .callbacks = { + .pre_patch = pre_patch_callback, + .post_patch = post_patch_callback, + .pre_unpatch = pre_unpatch_callback, + .post_unpatch = post_unpatch_callback, + }, + }, { + .name = "livepatch_callbacks_mod", + .funcs = no_funcs, + .callbacks = { + .pre_patch = pre_patch_callback, + .post_patch = post_patch_callback, + .pre_unpatch = pre_unpatch_callback, + .post_unpatch = post_unpatch_callback, + }, + }, { + .name = "livepatch_callbacks_busymod", + .funcs = busymod_funcs, + .callbacks = { + .pre_patch = pre_patch_callback, + .post_patch = post_patch_callback, + .pre_unpatch = pre_unpatch_callback, + .post_unpatch = post_unpatch_callback, + }, + }, { } +}; + +static struct klp_patch patch = { + .mod = THIS_MODULE, + .objs = objs, +}; + +static int livepatch_callbacks_demo_init(void) +{ + return klp_enable_patch(&patch); +} + +static void livepatch_callbacks_demo_exit(void) +{ +} + +module_init(livepatch_callbacks_demo_init); +module_exit(livepatch_callbacks_demo_exit); +MODULE_DESCRIPTION("Live patching demo for (un)patching callbacks"); +MODULE_LICENSE("GPL"); +MODULE_INFO(livepatch, "Y"); |
