From: Oleg Nesterov <oleg@redhat.com>
To: elfutils-devel@lists.fedorahosted.org
Subject: Re: [PATCH] Add --core-pattern option to eu-stack
Date: Wed, 26 Nov 2014 21:08:22 +0100 [thread overview]
Message-ID: <20141126200822.GB19810@redhat.com> (raw)
In-Reply-To: 20141126143239.GA16611@host2.jankratochvil.net
[-- Attachment #1: Type: text/plain, Size: 1175 bytes --]
On 11/26, Jan Kratochvil wrote:
>
> On Thu, 30 Oct 2014 22:55:41 +0100, Mark Wielaard wrote:
> > On Thu, 2014-10-09 at 23:25 +0200, Jan Kratochvil wrote:
> > > + if (opt_core_pattern == true && show_one_tid == false)
> > > + argp_error (state,
> > > + N_("--core-pattern requires -1"));
> >
> > Why this restriction?
>
> I was blindly following Oleg's note which was not so obvious to me, though:
>
> On Wed, 03 Sep 2014 16:26:41 +0200, Oleg Nesterov wrote:
> # Obviously, this way you can only inspect the thread which dumps the core.
>
> Therefore I have now tried to remove this limitation of
> -1 Show the backtrace of only one thread
>
> But I have found the other threads end up with:
> wait4(13902, [{WIFSIGNALED(s) && WTERMSIG(s) == SIGSEGV && WCOREDUMP(s)}], __WALL, NULL) = 13902
>
> Therefore they are dead at the core_pattern time, they cannot be ptraced and
> therefore they cannot be unwound.
Yes. I guess PTRACE_ATTACH should work but it is pointless, this
thread can't report an event and other ptrace requests won't work.
In fact I think PTRACE_ATTACH should fail in this case...
Oleg.
next reply other threads:[~2014-11-26 20:08 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-26 20:08 Oleg Nesterov [this message]
-- strict thread matches above, loose matches on Subject: below --
2014-11-28 15:04 Mark Wielaard
2014-11-28 14:44 Mark Wielaard
2014-11-28 14:27 Mark Wielaard
2014-11-27 21:47 Jan Kratochvil
2014-11-27 21:41 Jan Kratochvil
2014-11-27 21:27 Jan Kratochvil
2014-11-27 11:17 Mark Wielaard
2014-11-27 11:05 Mark Wielaard
2014-11-27 11:04 Mark Wielaard
2014-11-26 20:57 Oleg Nesterov
2014-11-26 20:26 Jan Kratochvil
2014-11-26 14:47 Jan Kratochvil
2014-11-26 14:44 Jan Kratochvil
2014-11-26 14:32 Jan Kratochvil
2014-11-03 13:22 Mark Wielaard
2014-10-30 21:55 Mark Wielaard
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=20141126200822.GB19810@redhat.com \
--to=oleg@redhat.com \
--cc=elfutils-devel@lists.fedorahosted.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).