From: Petr Tesarik <ptesarik@suse.cz>
To: Doug Evans <dje@google.com>
Cc: Jeff Mahoney <jeffm@suse.com>, Ales Novak <alnovak@suse.cz>,
gdb-patches <gdb-patches@sourceware.org>
Subject: Re: [PATCH 2/4] Add Jeff Mahoney's py-crash patches.
Date: Thu, 04 Feb 2016 17:25:00 -0000 [thread overview]
Message-ID: <20160204182508.289bb384@hananiah.suse.cz> (raw)
In-Reply-To: <CADPb22Q2G2_2LVGfkzLtj-445zR3TZKgLw-XsQPbdfoF2Z2bSg@mail.gmail.com>
Hi Doug,
On Wed, 3 Feb 2016 10:30:20 -0800
Doug Evans <dje@google.com> wrote:
> On Wed, Feb 3, 2016 at 9:55 AM, Jeff Mahoney <jeffm@suse.com> wrote:
> >...
> >>> Hi.
> >>
> >> Hi Doug -
> >>
> >>> Part of what this patch is doing is exporting bfd to python.
> >>> E.g., all the SEC_* constants.
> >>
> >>> As a rule we absolutely discourage people from using bfd outside
> >>> of the the binutils+gdb source tree. Either this rule needs to
> >>> change, or I don't think we can allow this patch. I'd be
> >>> interested to hear what others in the community think.
> >>
> >> That's unfortunate. The Linux kernel uses ELF sections for a
> >> number of purposes. Most notably is the definition of per-cpu
> >> variables. Without the ELF section, we can't resolve the addresses
> >> for the variables. So, from our perspective, it's a requirement.
> >>
> >>> For myself, I would much rather export ELF separately (e.g., a
> >>> separate python API one can use independent of any particular
> >>> tool, including gdb), and then have gdb provide the necessary
> >>> glue to use this API. [I can imagine some compromises being
> >>> needed, at least for now; e.g., it'd be cumbersome to read in all
> >>> ELF symbols twice. But fixing that is just an optimization.]
> >>
> >> Ok, that's doable. As it is, the section code mixes GDB and BFD
> >> pretty heavily. It shouldn't be too difficult to separate the two
> >> out and push the section stuff into a new BFD python interface and
> >> associate the objfiles with it.
> >
> > And here's what I've come up with. Does this constitute enough of a
> > separation? It /should/ cross over into the BFD code in the same way
> > that the GDB code does: As soon as we hit a bfd object or a
> > bfd_section object, we call into bfd's new python API to generate the
> > objects.
> >
> > https://jeffm.io/git/cgit.cgi/gnu/binutils-gdb/log/?h=gdb/python-bfd
> >
> > For the fully-integrated kdump work, use the python-bfd-kdump branch
> > (or SUSE folks, python-bfd-kdump-buildid will pick up the separate
> > debuginfos as we usually expect).
>
> Separation isn't the issue, unfortunately.
> The issue is that we cannot export bfd to python, period.
Excuse my ignorance, but can you explain a bit more why BFD should not
be used? I'm sure there has been some discussion on that topic; a
pointer in the right direction would be welcome.
TIA,
Petr Tesarik
next prev parent reply other threads:[~2016-02-04 17:25 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-31 21:45 Enable gdb to open Linux kernel dumps Ales Novak
2016-01-31 21:45 ` [PATCH 1/4] Create new target "kdump" which uses libkdumpfile: https://github.com/ptesarik/libkdumpfile to access contents of compressed kernel dump Ales Novak
2016-02-04 12:40 ` Pedro Alves
2016-02-04 12:45 ` Ales Novak
2016-01-31 21:45 ` [PATCH 2/4] Add Jeff Mahoney's py-crash patches Ales Novak
2016-02-01 12:35 ` Kieran Bingham
2016-02-01 22:23 ` Doug Evans
2016-02-02 2:56 ` Jeff Mahoney
2016-02-02 8:25 ` Kieran Bingham
2016-02-03 17:55 ` Jeff Mahoney
2016-02-03 18:31 ` Doug Evans
2016-02-03 19:29 ` Jeff Mahoney
2016-02-04 17:25 ` Petr Tesarik [this message]
2016-02-04 18:32 ` Matt Rice
2016-02-04 22:27 ` Doug Evans
2016-01-31 21:45 ` [PATCH 3/4] Add SLAB allocator understanding Ales Novak
2016-02-01 13:21 ` Kieran Bingham
2016-02-01 22:30 ` Doug Evans
2016-02-02 2:05 ` Ales Novak
2016-02-02 7:22 ` Jan Kiszka
2016-02-02 13:22 ` Petr Tesarik
2016-02-02 14:42 ` Jeff Mahoney
2016-02-02 8:11 ` Kieran Bingham
2016-02-02 10:04 ` Vlastimil Babka
2016-01-31 21:45 ` [PATCH 4/4] Minor cleanups Ales Novak
2016-02-01 11:27 ` Enable gdb to open Linux kernel dumps Kieran Bingham
2016-02-01 11:51 ` Kieran Bingham
2016-02-01 14:32 ` Ales Novak
2016-02-01 15:01 ` Jeff Mahoney
2016-02-02 9:12 ` Kieran Bingham
2016-02-10 3:24 ` Jeff Mahoney
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160204182508.289bb384@hananiah.suse.cz \
--to=ptesarik@suse.cz \
--cc=alnovak@suse.cz \
--cc=dje@google.com \
--cc=gdb-patches@sourceware.org \
--cc=jeffm@suse.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).