On Thursday 03/07 at 22:16 +0000, Christophe Leroy wrote: > > > Le 06/03/2024 à 21:05, Calvin Owens a écrit : > > [Vous ne recevez pas souvent de courriers de jcalvinowens@xxxxxxxxx. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ] > > > > If something like this is merged down the road, it can go in at leisure > > once the module_alloc change is in: it's a one-way dependency. > > Too many #ifdef, please reorganise stuff to avoid that and avoid > changing prototypes based of CONFIG_MODULES. > > Other few comments below. TBH the ugliness here was just me trying not to trigger -Wunused, but that was silly: as you point out below, it's unncessary. I'll clean it up. > > > > Signed-off-by: Calvin Owens <jcalvinowens@xxxxxxxxx> > > --- > > arch/Kconfig | 2 +- > > kernel/kprobes.c | 22 ++++++++++++++++++++++ > > kernel/trace/trace_kprobe.c | 11 +++++++++++ > > 3 files changed, 34 insertions(+), 1 deletion(-) > > > > diff --git a/arch/Kconfig b/arch/Kconfig > > index cfc24ced16dd..e60ce984d095 100644 > > --- a/arch/Kconfig > > +++ b/arch/Kconfig > > @@ -52,8 +52,8 @@ config GENERIC_ENTRY > > > > config KPROBES > > bool "Kprobes" > > - depends on MODULES > > depends on HAVE_KPROBES > > + select MODULE_ALLOC > > select KALLSYMS > > select TASKS_RCU if PREEMPTION > > help > > diff --git a/kernel/kprobes.c b/kernel/kprobes.c > > index 9d9095e81792..194270e17d57 100644 > > --- a/kernel/kprobes.c > > +++ b/kernel/kprobes.c > > @@ -1556,8 +1556,12 @@ static bool is_cfi_preamble_symbol(unsigned long addr) > > str_has_prefix("__pfx_", symbuf); > > } > > > > +#if IS_ENABLED(CONFIG_MODULES) > > static int check_kprobe_address_safe(struct kprobe *p, > > struct module **probed_mod) > > +#else > > +static int check_kprobe_address_safe(struct kprobe *p) > > +#endif > > A bit ugly to have to change the prototype, why not just keep probed_mod > at all time ? > > When CONFIG_MODULES is not selected, __module_text_address() returns > NULL so it should work without that many #ifdefs. > > > { > > int ret; > > > > @@ -1580,6 +1584,7 @@ static int check_kprobe_address_safe(struct kprobe *p, > > goto out; > > } > > > > +#if IS_ENABLED(CONFIG_MODULES) > > /* Check if 'p' is probing a module. */ > > *probed_mod = __module_text_address((unsigned long) p->addr); > > if (*probed_mod) { > > @@ -1603,6 +1608,8 @@ static int check_kprobe_address_safe(struct kprobe *p, > > ret = -ENOENT; > > } > > } > > +#endif > > + > > out: > > preempt_enable(); > > jump_label_unlock(); > > @@ -1614,7 +1621,9 @@ int register_kprobe(struct kprobe *p) > > { > > int ret; > > struct kprobe *old_p; > > +#if IS_ENABLED(CONFIG_MODULES) > > struct module *probed_mod; > > +#endif > > kprobe_opcode_t *addr; > > bool on_func_entry; > > > > @@ -1633,7 +1642,11 @@ int register_kprobe(struct kprobe *p) > > p->nmissed = 0; > > INIT_LIST_HEAD(&p->list); > > > > +#if IS_ENABLED(CONFIG_MODULES) > > ret = check_kprobe_address_safe(p, &probed_mod); > > +#else > > + ret = check_kprobe_address_safe(p); > > +#endif > > if (ret) > > return ret; > > > > @@ -1676,8 +1689,10 @@ int register_kprobe(struct kprobe *p) > > out: > > mutex_unlock(&kprobe_mutex); > > > > +#if IS_ENABLED(CONFIG_MODULES) > > if (probed_mod) > > module_put(probed_mod); > > +#endif > > > > return ret; > > } > > @@ -2482,6 +2497,7 @@ int kprobe_add_area_blacklist(unsigned long start, unsigned long end) > > return 0; > > } > > > > +#if IS_ENABLED(CONFIG_MODULES) > > /* Remove all symbols in given area from kprobe blacklist */ > > static void kprobe_remove_area_blacklist(unsigned long start, unsigned long end) > > { > > @@ -2499,6 +2515,7 @@ static void kprobe_remove_ksym_blacklist(unsigned long entry) > > { > > kprobe_remove_area_blacklist(entry, entry + 1); > > } > > +#endif > > > > int __weak arch_kprobe_get_kallsym(unsigned int *symnum, unsigned long *value, > > char *type, char *sym) > > @@ -2564,6 +2581,7 @@ static int __init populate_kprobe_blacklist(unsigned long *start, > > return ret ? : arch_populate_kprobe_blacklist(); > > } > > > > +#if IS_ENABLED(CONFIG_MODULES) > > static void add_module_kprobe_blacklist(struct module *mod) > > { > > unsigned long start, end; > > @@ -2665,6 +2683,7 @@ static struct notifier_block kprobe_module_nb = { > > .notifier_call = kprobes_module_callback, > > .priority = 0 > > }; > > +#endif /* IS_ENABLED(CONFIG_MODULES) */ > > > > void kprobe_free_init_mem(void) > > { > > @@ -2724,8 +2743,11 @@ static int __init init_kprobes(void) > > err = arch_init_kprobes(); > > if (!err) > > err = register_die_notifier(&kprobe_exceptions_nb); > > + > > +#if IS_ENABLED(CONFIG_MODULES) > > if (!err) > > err = register_module_notifier(&kprobe_module_nb); > > +#endif > > > > kprobes_initialized = (err == 0); > > kprobe_sysctls_init(); > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > > index c4c6e0e0068b..dd4598f775b9 100644 > > --- a/kernel/trace/trace_kprobe.c > > +++ b/kernel/trace/trace_kprobe.c > > @@ -102,6 +102,7 @@ static nokprobe_inline bool trace_kprobe_has_gone(struct trace_kprobe *tk) > > return kprobe_gone(&tk->rp.kp); > > } > > > > +#if IS_ENABLED(CONFIG_MODULES) > > static nokprobe_inline bool trace_kprobe_within_module(struct trace_kprobe *tk, > > struct module *mod) > > { > > @@ -129,6 +130,12 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) > > > > return ret; > > } > > +#else > > +static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk) > > +{ > > + return true; > > +} > > +#endif > > > > static bool trace_kprobe_is_busy(struct dyn_event *ev) > > { > > @@ -670,6 +677,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) > > return ret; > > } > > > > +#if IS_ENABLED(CONFIG_MODULES) > > /* Module notifier call back, checking event on the module */ > > static int trace_kprobe_module_callback(struct notifier_block *nb, > > unsigned long val, void *data) > > @@ -704,6 +712,7 @@ static struct notifier_block trace_kprobe_module_nb = { > > .notifier_call = trace_kprobe_module_callback, > > .priority = 1 /* Invoked after kprobe module callback */ > > }; > > +#endif /* IS_ENABLED(CONFIG_MODULES) */ > > > > static int count_symbols(void *data, unsigned long unused) > > { > > @@ -1897,8 +1906,10 @@ static __init int init_kprobe_trace_early(void) > > if (ret) > > return ret; > > > > +#if IS_ENABLED(CONFIG_MODULES) > > if (register_module_notifier(&trace_kprobe_module_nb)) > > return -EINVAL; > Why a #if here ? > > If CONFIG_MODULES is not selected, register_module_notifier() return > always 0. > > > +#endif > > > > return 0; > > } > > -- > > 2.43.0 > > > >
