From: "Daniel Walker \(danielwa\) via Libc-alpha" <libc-alpha@sourceware.org>
To: Florian Weimer <fweimer@redhat.com>
Cc: "Nikola Tesic -X \(ntesic - SYRMIA DOO NOVI SAD at Cisco\)"
<ntesic@cisco.com>,
"libc-alpha@sourceware.org" <libc-alpha@sourceware.org>,
Pedro Alves <palves@redhat.com>,
"Jeremy Stenglein \(jstengle\)" <jstengle@cisco.com>,
"xe-linux-external\(mailer list\)" <xe-linux-external@cisco.com>
Subject: Re: [RFC PATCH 0/3] implement dlmopen hooks for gdb
Date: Mon, 21 Sep 2020 20:02:16 +0000 [thread overview]
Message-ID: <20200921200216.GQ7261@zorba> (raw)
In-Reply-To: <87imcb3xg1.fsf@oldenburg2.str.redhat.com>
On Fri, Sep 18, 2020 at 05:40:30PM +0200, Florian Weimer wrote:
> * Daniel Walker:
>
> > On Thu, Sep 17, 2020 at 09:53:30AM -0400, Carlos O'Donell wrote:
> >> On 9/17/20 8:59 AM, Florian Weimer wrote:
> >> > * Carlos O'Donell:
> >> >
> >> >> You will always have .dynsym with a definition for _r_debug_dlmopen.
> >> >
> >> > Note that this doesn't work if you just have a core file. In order to
> >> > find _r_debug (or _r_debug_dlmopen), a debugger needs the exact same
> >> > copy of ld.so that was used by the executable, otherwise the symbol
> >> > cannot be found in the image.
> >>
> >> You are correct.
> >>
> >> I followed up on my own email regarding this.
> >>
> >> So in the end to get process and core file debugging we'll need:
> >>
> >> * _r_debug_dlmopen
> >> * DT_DEBUG_DLMOPEN
> >>
> >
> > It seems like adding DT_DEBUG_DLMOPEN into the gABI might take some
> > effort. Have you considered this ? The last one which was added was
> > DT_SYMTAB_SHNDX in 2018, and it looks like it did not come from glibc.
>
> We are reviving GNU gABI maintenance. There's been quite a bit of list
> activity, and a proposal of a first ABI document:
>
> <https://sourceware.org/pipermail/gnu-gabi/2020q3/thread.html>
>
> I have a feeling that we might be soon over this bump, and getting
> things added should become easier.
>
> In the meantime, can we demo this feature without DT_DEBUG_DLMOPEN?
> With a patch glibc and gdb? Incidentally, I have an LD_AUDIT issue I
> need to debug. 8-)
>
The only fully working version we have is the one I released originally. Yes,
that version had no DT_DEBUG_DLMOPEN. It should be working and you can demo it.
We're still working on updating GDB to use the new interfaces.
In terms of updating the gABI, should I just add a patch to glibc to add values
or do I need special documents to be submitted ?
Daniel
next prev parent reply other threads:[~2020-09-21 20:02 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-26 19:32 [RFC PATCH 0/3] implement dlmopen hooks for gdb Daniel Walker via Libc-alpha
2020-06-26 21:17 ` Carlos O'Donell via Libc-alpha
2020-07-23 18:40 ` Daniel Walker (danielwa) via Libc-alpha
2020-07-23 21:20 ` Carlos O'Donell via Libc-alpha
2020-09-16 16:18 ` Daniel Walker (danielwa) via Libc-alpha
2020-09-17 12:52 ` Carlos O'Donell via Libc-alpha
2020-09-17 12:59 ` Florian Weimer via Libc-alpha
2020-09-17 13:53 ` Carlos O'Donell via Libc-alpha
2020-09-18 15:35 ` Daniel Walker (danielwa) via Libc-alpha
2020-09-18 15:40 ` Florian Weimer via Libc-alpha
2020-09-21 20:02 ` Daniel Walker (danielwa) via Libc-alpha [this message]
2021-07-28 18:33 ` Daniel Walker via Libc-alpha
2021-07-28 18:48 ` H.J. Lu via Libc-alpha
2020-09-17 13:52 ` Carlos O'Donell via Libc-alpha
2020-09-22 17:06 ` Florian Weimer via Libc-alpha
2020-09-22 17:28 ` Carlos O'Donell via Libc-alpha
2020-09-22 17:37 ` Florian Weimer via Libc-alpha
2020-09-22 17:59 ` Carlos O'Donell via Libc-alpha
2020-09-22 18:04 ` Florian Weimer via Libc-alpha
2020-09-22 18:41 ` Carlos O'Donell via Libc-alpha
2020-09-22 18:44 ` Florian Weimer via Libc-alpha
2020-09-22 18:46 ` Carlos O'Donell via Libc-alpha
2020-09-22 18:17 ` Andreas Schwab
2020-09-22 19:13 ` Carlos O'Donell via Libc-alpha
2020-06-26 21:30 ` Florian Weimer via Libc-alpha
2020-06-27 1:10 ` Daniel Walker (danielwa) via Libc-alpha
2020-07-02 13:54 ` Conan Huang (conhuang) via Libc-alpha
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