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Date: Wed, 02 Jul 2014 15:39:25 +0900
From: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Organization: Hitachi, Ltd., Japan
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To: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
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Subject: Re: Re: Re: [PATCH v4] [BUGFIX] kprobes: Fix "Failed to find blacklist"
 error on ia64 and ppc64
References: <20140620022307.23075.55858.stgit@kbuild-fedora.novalocal>   <53B0D61B.9010104@hitachi.com> <1404128176.7888.1.camel@concordia>  <53B21B0E.8010707@hitachi.com> <1404276081.7254.1.camel@concordia>
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(2014/07/02 13:41), Michael Ellerman wrote:
> On Tue, 2014-07-01 at 11:21 +0900, Masami Hiramatsu wrote:
>> (2014/06/30 20:36), Michael Ellerman wrote:
>>> On Mon, 2014-06-30 at 12:14 +0900, Masami Hiramatsu wrote:
>>>> Ping? :)
>>>
>>> Yeah sorry. I started looking at this and got dragged into another mess.
>>>
>>> You seem to have duplicated the functionality of arch_deref_entry_point(),
>>> which was also added for kprobes, and for the same reason - ie. because some
>>> arches have strange function pointers. Is there some reason you can't use it?
>>
>> Ah, right! Hmm, it seems some more work to update it. but basically, we can do.
>> BTW, is there any other users who need to access the actual function entry (for
>> kallsyms case)?
> 
> Not that I'm aware of. We have had function descriptors on 64-bit powerpc for
> ever, so in theory by now we should have already found any cases where we need
> that sort of wrapper.

OK, then I'll update this patch to use arch_deref_entry_point(), and add additional
patch which update to support PPC64 ABIv2.

Thank you!

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