Messages in this thread Patch in this message | | | From | Jarkko Sakkinen <> | Subject | [PATCH 3/3] kprobes: Flag out CONFIG_MODULES dependent code | Date | Mon, 13 Jul 2020 21:19:39 +0300 |
| |
Remove CONFIG_MODULES dependency by flagging out the dependent code. This allows to use kprobes in a kernel without support for loadable modules, which could be useful for a test kernel or perhaps an embedded kernel.
Cc: Andi Kleen <ak@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> --- arch/Kconfig | 1 - include/linux/module.h | 14 +++++++------- kernel/kprobes.c | 9 +++++++++ kernel/trace/trace_kprobe.c | 16 +++++++++++++++- 4 files changed, 31 insertions(+), 9 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig index 8cc35dc556c7..bb59cdf335ab 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -61,7 +61,6 @@ config OPROFILE_NMI_TIMER config KPROBES bool "Kprobes" - depends on MODULES depends on HAVE_KPROBES select KALLSYMS help diff --git a/include/linux/module.h b/include/linux/module.h index 857b84bf9e90..eaa8ad02f75c 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -290,6 +290,13 @@ extern typeof(name) __mod_##type##__##name##_device_table \ struct notifier_block; +enum module_state { + MODULE_STATE_LIVE, /* Normal state. */ + MODULE_STATE_COMING, /* Full formed, running module_init. */ + MODULE_STATE_GOING, /* Going away. */ + MODULE_STATE_UNFORMED, /* Still setting it up. */ +}; + #ifdef CONFIG_MODULES extern int modules_disabled; /* for sysctl */ @@ -305,13 +312,6 @@ struct module_use { struct module *source, *target; }; -enum module_state { - MODULE_STATE_LIVE, /* Normal state. */ - MODULE_STATE_COMING, /* Full formed, running module_init. */ - MODULE_STATE_GOING, /* Going away. */ - MODULE_STATE_UNFORMED, /* Still setting it up. */ -}; - struct mod_tree_node { struct module *mod; struct latch_tree_node node; diff --git a/kernel/kprobes.c b/kernel/kprobes.c index bbe3423cb2b8..047353008cb6 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1608,6 +1608,7 @@ static int check_kprobe_address_safe(struct kprobe *p, goto out; } +#ifdef CONFIG_MODULES /* * If the module freed .init.text, we couldn't insert * kprobes in there. @@ -1618,6 +1619,7 @@ static int check_kprobe_address_safe(struct kprobe *p, *probed_mod = NULL; ret = -ENOENT; } +#endif } out: preempt_enable(); @@ -2214,6 +2216,7 @@ int kprobe_add_area_blacklist(unsigned long start, unsigned long end) return 0; } +#ifdef CONFIG_MODULES /* Remove all symbols in given area from kprobe blacklist */ static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) { @@ -2231,6 +2234,7 @@ static void kprobe_remove_ksym_blacklist(unsigned long entry) { kprobe_remove_area_blacklist(entry, entry + 1); } +#endif int __init __weak arch_populate_kprobe_blacklist(void) { @@ -2274,6 +2278,7 @@ static int __init populate_kprobe_blacklist(unsigned long *start, return ret ? : arch_populate_kprobe_blacklist(); } +#ifdef CONFIG_MODULES static void add_module_kprobe_blacklist(struct module *mod) { unsigned long start, end; @@ -2319,6 +2324,10 @@ static void remove_module_kprobe_blacklist(struct module *mod) kprobe_remove_area_blacklist(start, end); } } +#else +static void add_module_kprobe_blacklist(struct module *mod) {} +static void remove_module_kprobe_blacklist(struct module *mod) {} +#endif /* CONFIG_MODULES */ /* Module notifier call back, checking kprobes on the module */ static int kprobes_module_callback(struct notifier_block *nb, diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 710ec6a6aa8f..7fcd1bf2d96e 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -103,8 +103,9 @@ static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) return !!(kprobe_gone(&tk->rp.kp)); } +#ifdef CONFIG_MODULES static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, - struct module *mod) + struct module *mod) { int len = strlen(mod->name); const char *name = trace_kprobe_symbol(tk); @@ -129,6 +130,17 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) return ret; } +#else +static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, + struct module *mod) +{ + return false; +} +static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) +{ + return false; +} +#endif static bool trace_kprobe_is_busy(struct dyn_event *ev) { @@ -685,10 +697,12 @@ static int trace_kprobe_module_callback(struct notifier_block *nb, /* Don't need to check busy - this should have gone. */ __unregister_trace_kprobe(tk); ret = __register_trace_kprobe(tk); +#ifdef CONFIG_MODULES if (ret) pr_warn("Failed to re-register probe %s on %s: %d\n", trace_probe_name(&tk->tp), mod->name, ret); +#endif } } mutex_unlock(&event_mutex); -- 2.25.1
| |