Re: Re: [PATCH v5 2/2] [BUGFIX] kprobes: Fix "Failed to find blacklist" error on ia64 and ppc64

Masami Hiramatsu
2014-07-15T02:24:49Z

(2014/07/15 11:11), Michael Ellerman wrote:
> On Mon, 2014-07-14 at 10:17 -0700, Tony Luck wrote:
>> On Tue, Jul 8, 2014 at 5:07 AM, Masami Hiramatsu
>> <masami.hiramatsu.pt@hitachi.com> wrote:
>>> Ping?
>>>
>>> This patch can be applied without 1/2, and will fix ia64/ppc64 problem.
>>
>> Is somebody going to push this upstream? Another week has gone by,
>> we are at -rc5, and I'm still seeing the
>>
>> Failed to find blacklist a00000010133b150
>>
>> messages on ia64.
>
> I don't see those messages on ppc64, I don't know where the original report
> that it was broken on ppc64 came from. So I'm a bit lukewarm on the patch.

Right, on ppc64(ABIv1) it may be silently failed. Because each function
descriptor has another entry on kallsyms, original code can't detect
that. On the other hand, ia64's function descriptors have no entries,
so it can detect the failure on boot.

This patch adds new detection code using kernel_text_address() and
translates function descriptor to function entry.

Thank you,

--
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@hitachi.com