From: Samuel Bronson <naesten@gmail.com>
To: binutils@sourceware.org
Cc: gdb@sourceware.org
Subject: Re: vdso handling
Date: Sun, 01 Jun 2014 23:45:00 -0000 [thread overview]
Message-ID: <87a99w2wxw.fsf@naesten.mooo.com> (raw)
In-Reply-To: <53218C92.9050303@redhat.com>
Pedro Alves <palves@redhat.com> writes:
> On 03/13/2014 10:07 AM, Pedro Alves wrote:
>> Why's that? Why doesn't the memory-backed bfd paths take the same paths as
>> a file-backed bfd internally in bfd? It sounds to me that this should be
>> doable without duplication.
>
> BTW, I meant that for vDSO's only. The vsyscall page is not an elf,
> and therefore bfd still needs to be passed a template elf. For the
> latter, GDB would indeed need to work with the segments. Do we still
> care for vsyscall kernels? But for the former, bfd should just be
> able to read the whole DSO as a plain elf.
>
> Some glibc versions even include the vdso in the DSO list (*), and GDB
> should be able to tell that that DSO is the vDSO (by matching addresses), and
^^^^^^^^^^^^^^^^^^^^^
Hmm, why don't we already do that? It's bound to be easier than meeting
the conditions to get glibc to stop falsely cliaming that the vDSO comes
from a file <https://sourceware.org/bugzilla/show_bug.cgi?id=13097#c5>.
That'd be enough to take two bugs off of <http://bugs.debian.org/gdb>
right there.
> load it completely from memory, still using a memory backed bfd, but _without_
> a template. So with that in mind, bfd should be able to read the vdso
> as a bfd from memory using the same paths as a file-backed bfd, except,
> well, the bfd's backing store is in memory rather than in a file.
>
> (*) note how linux-vdso.so.1 is listed by ldd, even if "info shared" in gdb
> doesn't show it, on some systems.
What versions don't list the vdso under some name or other? (Mine calls
it linux-gate.so.1 for some reason.)
--
Hi! I'm a .signature virus! Copy me into your ~/.signature to help me spread!
next prev parent reply other threads:[~2014-06-01 23:45 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-10 13:05 Metzger, Markus T
2014-03-12 7:17 ` Alan Modra
2014-03-12 11:31 ` Mike Frysinger
2014-03-12 17:34 ` Doug Evans
2014-03-12 20:23 ` Cary Coutant
2014-03-13 1:01 ` Alan Modra
2014-03-13 8:25 ` Metzger, Markus T
2014-03-13 9:48 ` Metzger, Markus T
2014-03-13 10:07 ` Pedro Alves
2014-03-13 10:46 ` Pedro Alves
2014-06-01 23:45 ` Samuel Bronson [this message]
2014-06-06 12:45 ` Pedro Alves
2014-03-13 13:13 ` Alan Modra
2014-03-13 9:52 ` Mark Wielaard
2014-03-13 13:03 ` Alan Modra
2014-03-13 14:38 ` Mark Wielaard
2014-03-13 14:59 ` Pedro Alves
2014-03-13 15:04 ` Pedro Alves
2014-03-13 15:26 ` Pedro Alves
2014-03-13 23:53 ` Alan Modra
2014-03-18 15:14 ` Metzger, Markus T
2014-03-18 23:10 ` Alan Modra
2014-03-19 8:11 ` Metzger, Markus T
2014-03-19 8:31 ` Metzger, Markus T
2014-03-19 12:04 ` Pedro Alves
2014-03-20 2:00 ` Alan Modra
2014-03-21 15:55 ` Pedro Alves
2014-03-26 9:32 ` Metzger, Markus T
2014-03-19 12:03 ` Pedro Alves
2014-03-20 1:33 ` Alan Modra
2014-03-21 8:10 ` Metzger, Markus T
2014-03-21 15:48 ` Pedro Alves
2014-03-28 6:13 ` Alan Modra
2014-03-28 13:38 ` Pedro Alves
2014-03-28 23:00 ` Alan Modra
2014-04-01 13:46 ` Pedro Alves
2014-04-02 1:50 ` Alan Modra
2014-04-02 8:05 ` Metzger, Markus T
2014-04-02 8:04 ` Hans-Peter Nilsson
2014-04-03 1:06 ` Alan Modra
2014-04-03 1:46 ` Alan Modra
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=87a99w2wxw.fsf@naesten.mooo.com \
--to=naesten@gmail.com \
--cc=binutils@sourceware.org \
--cc=gdb@sourceware.org \
/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).