Re: [PATCH] include/linux/kprobes.h: move all functions to theirmatched area

From: Masami Hiramatsu
Date: Wed Feb 05 2014 - 02:51:30 EST


(2014/02/05 14:27), Chen Gang wrote:
> For dummy functions, it is not a good idea to still use the input
> parameters (not a good idea to assume they are still effect).
>
> - let kprobe* static inline functions in CONFIG_KPROBES, dummy outside.
>
> - let (en/dis)able_jprobe() in CONFIG_KPROBES, dummy outside.
>
> - for kretprobe:
>
> - let kretprobe_assert() only in CONFIG_KRETPROBES (internal use).
>
> - remove kretprobe_inst_table_head() (cannot grep it in kernel wide).
>
> - for (en/dis)able_kretprobe():
>
> if CONFIG_KRETPROBES enabled, they use (en/dis)able_kprobe().
> else if CONFIG_KPROBES enabled, return -EINVAL (not registered).
> else, return -ENOSYS, just like (en/dis)able_kprobe() have done.

NAK. I don't increase complexity in this header file anymore,
unless we have any actual issue with sane usage.

Thank you,

>
>
> Signed-off-by: Chen Gang <gang.chen.5i5j@xxxxxxxxx>
> ---
> include/linux/kprobes.h | 136 ++++++++++++++++++++++++++++++++----------------
> 1 file changed, 92 insertions(+), 44 deletions(-)
>
> diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
> index 925eaf2..860313d 100644
> --- a/include/linux/kprobes.h
> +++ b/include/linux/kprobes.h
> @@ -129,30 +129,6 @@ struct kprobe {
> */
> #define KPROBE_FLAG_FTRACE 8 /* probe is using ftrace */
>
> -/* Has this kprobe gone ? */
> -static inline int kprobe_gone(struct kprobe *p)
> -{
> - return p->flags & KPROBE_FLAG_GONE;
> -}
> -
> -/* Is this kprobe disabled ? */
> -static inline int kprobe_disabled(struct kprobe *p)
> -{
> - return p->flags & (KPROBE_FLAG_DISABLED | KPROBE_FLAG_GONE);
> -}
> -
> -/* Is this kprobe really running optimized path ? */
> -static inline int kprobe_optimized(struct kprobe *p)
> -{
> - return p->flags & KPROBE_FLAG_OPTIMIZED;
> -}
> -
> -/* Is this kprobe uses ftrace ? */
> -static inline int kprobe_ftrace(struct kprobe *p)
> -{
> - return p->flags & KPROBE_FLAG_FTRACE;
> -}
> -
> /*
> * Special probe type that uses setjmp-longjmp type tricks to resume
> * execution at a specified entry with a matching prototype corresponding
> @@ -223,7 +199,42 @@ static inline int kprobes_built_in(void)
> return 1;
> }
>
> +/* Has this kprobe gone ? */
> +static inline int kprobe_gone(struct kprobe *p)
> +{
> + return p->flags & KPROBE_FLAG_GONE;
> +}
> +
> +/* Is this kprobe disabled ? */
> +static inline int kprobe_disabled(struct kprobe *p)
> +{
> + return p->flags & (KPROBE_FLAG_DISABLED | KPROBE_FLAG_GONE);
> +}
> +
> +/* Is this kprobe really running optimized path ? */
> +static inline int kprobe_optimized(struct kprobe *p)
> +{
> + return p->flags & KPROBE_FLAG_OPTIMIZED;
> +}
> +
> +/* Is this kprobe uses ftrace ? */
> +static inline int kprobe_ftrace(struct kprobe *p)
> +{
> + return p->flags & KPROBE_FLAG_FTRACE;
> +}
> +
> #ifdef CONFIG_KRETPROBES
> +static inline void kretprobe_assert(struct kretprobe_instance *ri,
> + unsigned long orig_ret_address, unsigned long trampoline_address)
> +{
> + if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
> + printk(KERN_ERR
> + "kretprobe BUG!: Processing kretprobe %p @ %p\n",
> + ri->rp, ri->rp->kp.addr);
> + BUG();
> + }
> +}
> +
> extern void arch_prepare_kretprobe(struct kretprobe_instance *ri,
> struct pt_regs *regs);
> extern int arch_trampoline_kprobe(struct kprobe *p);
> @@ -240,16 +251,6 @@ static inline int arch_trampoline_kprobe(struct kprobe *p)
>
> extern struct kretprobe_blackpoint kretprobe_blacklist[];
>
> -static inline void kretprobe_assert(struct kretprobe_instance *ri,
> - unsigned long orig_ret_address, unsigned long trampoline_address)
> -{
> - if (!orig_ret_address || (orig_ret_address == trampoline_address)) {
> - printk("kretprobe BUG!: Processing kretprobe %p @ %p\n",
> - ri->rp, ri->rp->kp.addr);
> - BUG();
> - }
> -}
> -
> #ifdef CONFIG_KPROBES_SANITY_TEST
> extern int init_test_probes(void);
> #else
> @@ -340,7 +341,6 @@ struct kprobe *get_kprobe(void *addr);
> void kretprobe_hash_lock(struct task_struct *tsk,
> struct hlist_head **head, unsigned long *flags);
> void kretprobe_hash_unlock(struct task_struct *tsk, unsigned long *flags);
> -struct hlist_head * kretprobe_inst_table_head(struct task_struct *tsk);
>
> /* kprobe_running() will just return the current_kprobe on this CPU */
> static inline struct kprobe *kprobe_running(void)
> @@ -384,12 +384,60 @@ int enable_kprobe(struct kprobe *kp);
>
> void dump_kprobe(struct kprobe *kp);
>
> +static inline int disable_jprobe(struct jprobe *jp)
> +{
> + return disable_kprobe(&jp->kp);
> +}
> +
> +static inline int enable_jprobe(struct jprobe *jp)
> +{
> + return enable_kprobe(&jp->kp);
> +}
> +
> +#ifdef CONFIG_KRETPROBES
> +static inline int disable_kretprobe(struct kretprobe *rp)
> +{
> + return disable_kprobe(&rp->kp);
> +}
> +
> +static inline int enable_kretprobe(struct kretprobe *rp)
> +{
> + return enable_kprobe(&rp->kp);
> +}
> +
> +#else /* CONFIG_KRETPROBES */
> +static inline int disable_kretprobe(struct kretprobe *rp)
> +{
> + return -EINVAL;
> +}
> +static inline int enable_kretprobe(struct kretprobe *rp)
> +{
> + return -EINVAL;
> +}
> +#endif /* CONFIG_KRETPROBES */
> +
> #else /* !CONFIG_KPROBES: */
>
> static inline int kprobes_built_in(void)
> {
> return 0;
> }
> +static inline int kprobe_gone(struct kprobe *p)
> +{
> + return 1;
> +}
> +static inline int kprobe_disabled(struct kprobe *p)
> +{
> + return 1;
> +}
> +static inline int kprobe_optimized(struct kprobe *p)
> +{
> + return 0;
> +}
> +static inline int kprobe_ftrace(struct kprobe *p)
> +{
> + return 0;
> +}
> static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
> {
> return 0;
> @@ -458,22 +506,22 @@ static inline int enable_kprobe(struct kprobe *kp)
> {
> return -ENOSYS;
> }
> -#endif /* CONFIG_KPROBES */
> -static inline int disable_kretprobe(struct kretprobe *rp)
> +static inline int disable_jprobe(struct jprobe *jp)
> {
> - return disable_kprobe(&rp->kp);
> + return -ENOSYS;
> }
> -static inline int enable_kretprobe(struct kretprobe *rp)
> +static inline int enable_jprobe(struct jprobe *jp)
> {
> - return enable_kprobe(&rp->kp);
> + return -ENOSYS;
> }
> -static inline int disable_jprobe(struct jprobe *jp)
> +static inline int disable_kretprobe(struct kretprobe *rp)
> {
> - return disable_kprobe(&jp->kp);
> + return -ENOSYS;
> }
> -static inline int enable_jprobe(struct jprobe *jp)
> +static inline int enable_kretprobe(struct kretprobe *rp)
> {
> - return enable_kprobe(&jp->kp);
> + return -ENOSYS;
> }
> +#endif /* CONFIG_KPROBES */
>
> #endif /* _LINUX_KPROBES_H */
>


--
Masami HIRAMATSU
IT Management Research Dept. Linux Technology Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@xxxxxxxxxxx


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