Re: [PATCH] Remove kretprobe_trampoline_holder.

["Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>]

On 2016/03/28 05:06PM, Thiago Jung Bauermann wrote:
> Fixes the following testsuite failure:
> 
> $ sudo ./perf test -v kallsyms
>  1: vmlinux symtab matches kallsyms                          :
> --- start ---
> test child forked, pid 12489
> Using /proc/kcore for kernel object code
> Looking at the vmlinux_path (8 entries long)
> Using /boot/vmlinux for symbols
> 0xc00000000003d300: diff name v: .kretprobe_trampoline_holder k: kretprobe_trampoline
> Maps only in vmlinux:
>  c00000000086ca38-c000000000879b6c 87ca38 [kernel].text.unlikely
>  c000000000879b6c-c000000000bf0000 889b6c [kernel].meminit.text
>  c000000000bf0000-c000000000c53264 c00000 [kernel].init.text
>  c000000000c53264-d000000004250000 c63264 [kernel].exit.text
>  d000000004250000-d000000004450000 0 [libcrc32c]
>  d000000004450000-d000000004620000 0 [xfs]
>  d000000004620000-d000000004680000 0 [autofs4]
>  d000000004680000-d0000000046e0000 0 [x_tables]
>  d0000000046e0000-d000000004780000 0 [ip_tables]
>  d000000004780000-d0000000047e0000 0 [rng_core]
>  d0000000047e0000-ffffffffffffffff 0 [pseries_rng]
> Maps in vmlinux with a different name in kallsyms:
> Maps only in kallsyms:
>  d000000000000000-f000000000000000 1000000000010000 [kernel.kallsyms]
>  f000000000000000-ffffffffffffffff 3000000000010000 [kernel.kallsyms]
> test child finished with -1
> ---- end ----
> vmlinux symtab matches kallsyms: FAILED!

You should indent the above output -- in this specific case, the start 
marker interferes with git am.

Apart from that, I have tested this patch and kretprobe works fine. A 
minor nit I had is that we end up with a non-dot function in .text 
without a corresponding function descriptor for kretprobe_trampoline.  
But, since this is a trampoline, I think that is good. So, for this 
patch:
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>


- Naveen