Hi Masami, > --- a/include/linux/kprobes.h > +++ b/include/linux/kprobes.h > @@ -205,15 +205,23 @@ extern void arch_prepare_kretprobe(struct kretprobe_instance *ri, > struct pt_regs *regs); > extern int arch_trampoline_kprobe(struct kprobe *p); > > +void kretprobe_trampoline(void); > +/* > + * Since some architecture uses structured function pointer, > + * use arch_deref_entry_point() to get real function address. s/arch_deref_entry_point/dereference_function_descriptor/ ? > + */ > +static nokprobe_inline void *kretprobe_trampoline_addr(void) > +{ > + return dereference_function_descriptor(kretprobe_trampoline); > +} > + Would it make sense to use this in s390 and powerpc reliable unwinders? Both arch/s390/kernel/stacktrace.c:arch_stack_walk_reliable() arch/powerpc/kernel/stacktrace.c:__save_stack_trace_tsk_reliable() have if (state.ip == (unsigned long)kretprobe_trampoline) return -EINVAL; which you wanted to hide previously if I am not mistaken. Miroslav