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Subject: Re: Re: Re: [PATCH v4] [BUGFIX] kprobes: Fix "Failed to find
 blacklist" error on ia64 and ppc64
From: Michael Ellerman <mpe@ellerman.id.au>
To: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Date: Wed, 02 Jul 2014 16:56:05 +1000
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Cc: Jeremy Fitzhardinge <jeremy@goop.org>, linux-ia64@vger.kernel.org,
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On Wed, 2014-07-02 at 15:39 +0900, Masami Hiramatsu wrote:
> (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.

I've already done the latter:

  https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=2f0143c91d30823f6f6e7d94d7fa818f7ab18a18

cheers