Messages in this thread Patch in this message | | | From | Wang Nan <> | Subject | [RFC PATCH v4 23/34] ftrace: notify kprobe when ftrace is initialized. | Date | Mon, 2 Mar 2015 22:25:01 +0800 |
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Makes ftrace calls init_kprobes_on_ftrace() when ftrace_init() finished. Before this call, marks kprobes on ftrace with 'KPROBE_FLAG_FTRACE_EARLY' instead of 'KPROBE_FLAG_FTRACE' to make kprobe not to kprobe treats these kprobes as ftrace kprobes.
Following patches should convert such kprobes into kprobes on ftrace.
Signed-off-by: Wang Nan <wangnan0@huawei.com> --- include/linux/kprobes.h | 11 +++++++++++ kernel/kprobes.c | 17 ++++++++++++++++- kernel/trace/ftrace.c | 2 ++ 3 files changed, 29 insertions(+), 1 deletion(-)
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index bb2b2c6..96dc842 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -130,6 +130,8 @@ struct kprobe { * this flag is only for optimized_kprobe. */ #define KPROBE_FLAG_FTRACE 8 /* probe is using ftrace */ +/* probe will use ftrace, but ftrace is not ready when registering */ +#define KPROBE_FLAG_FTRACE_EARLY 16 /* Has this kprobe gone ? */ static inline int kprobe_gone(struct kprobe *p) @@ -269,6 +271,14 @@ extern void show_registers(struct pt_regs *regs); extern void kprobes_inc_nmissed_count(struct kprobe *p); extern bool arch_within_kprobe_blacklist(unsigned long addr); +#if defined(CONFIG_EARLY_KPROBES) && defined(CONFIG_KPROBES_ON_FTRACE) +extern void init_kprobes_on_ftrace(void); +#else +static inline void init_kprobes_on_ftrace(void) +{ +} +#endif // CONFIG_EARLY_KPROBES && CONFIG_KPROBES_ON_FTRACE + #ifdef CONFIG_EARLY_KPROBES #define NR_EARLY_KPROBES_SLOTS CONFIG_NR_EARLY_KPROBES_SLOTS @@ -453,6 +463,7 @@ extern int proc_kprobes_optimization_handler(struct ctl_table *table, extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *ops, struct pt_regs *regs); extern int arch_prepare_kprobe_ftrace(struct kprobe *p); + #endif int arch_check_ftrace_location(struct kprobe *p); diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 4b7b20a..b5e13ba 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -69,6 +69,11 @@ static int kprobes_initialized; static int kprobes_blacklist_initialized; +#if defined(CONFIG_KPROBES_ON_FTRACE) && defined(CONFIG_EARLY_KPROBES) +static bool kprobes_on_ftrace_initialized __read_mostly = false; +#else +# define kprobes_on_ftrace_initialized false +#endif bool kprobes_is_early(void) { @@ -1497,7 +1502,10 @@ int __weak arch_check_ftrace_location(struct kprobe *p) /* Given address is not on the instruction boundary */ if ((unsigned long)p->addr != ftrace_addr) return -EILSEQ; - p->flags |= KPROBE_FLAG_FTRACE; + if (unlikely(!kprobes_on_ftrace_initialized)) + p->flags |= KPROBE_FLAG_FTRACE_EARLY; + else + p->flags |= KPROBE_FLAG_FTRACE; #else /* !CONFIG_KPROBES_ON_FTRACE */ return -EINVAL; #endif @@ -2574,3 +2582,10 @@ module_init(init_kprobes); /* defined in arch/.../kernel/kprobes.c */ EXPORT_SYMBOL_GPL(jprobe_return); + +#if defined(CONFIG_KPROBES_ON_FTRACE) && defined(CONFIG_EARLY_KPROBES) +void init_kprobes_on_ftrace(void) +{ + kprobes_on_ftrace_initialized = true; +} +#endif diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 7fa88d0..5cb0269 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -23,6 +23,7 @@ #include <linux/kthread.h> #include <linux/uaccess.h> #include <linux/bsearch.h> +#include <linux/kprobes.h> #include <linux/module.h> #include <linux/ftrace.h> #include <linux/sysctl.h> @@ -5022,6 +5023,7 @@ void __init ftrace_init(void) if (ret) pr_warning("Failed to register trace ftrace module exit notifier\n"); + init_kprobes_on_ftrace(); set_ftrace_early_filters(); return; -- 1.8.4
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