Default [Q] kmemleak backtrace return address

I have been learning to use kmemleak and I have an issue resolving the refrences in the backtrace section.
Code:
backtrace:
    [<c0282458>] create_object+0x12c/0x2b4
    [<c0a38540>] kmemleak_alloc+0x48/0x80
    [<c027d5d0>] kmalloc_order_trace+0x4c/0xf0
    [<c065f5c0>] mass_storage_function_init+0x590/0xd08
    [<c06691b4>] android_bind+0x21c/0x814

Code:
$ arm-linux-androideabi-addr2line -f -e vmlinux c06691b4
android_bind
android.c:?
I am expecting the '?' to be a number in the last line 'android.c:?'

Can someone suggest how to get the proper results?
I'm reckless with my devices. I'm just warning you!