mailing list of musl libc
 help / color / mirror / code / Atom feed
From: Jens Gustedt <jens.gustedt@inria.fr>
To: musl@lists.openwall.com
Subject: Re: Explaining cond var destroy [Re: [musl] C threads, v3.0]
Date: Thu, 07 Aug 2014 00:43:35 +0200	[thread overview]
Message-ID: <1407365015.24324.334.camel@eris.loria.fr> (raw)
In-Reply-To: <20140806220453.GD1674@brightrain.aerifal.cx>

[-- Attachment #1: Type: text/plain, Size: 985 bytes --]

Am Mittwoch, den 06.08.2014, 18:04 -0400 schrieb Rich Felker:
> No. The problem is that the memory in which the cond var resides could
> previously have been used for a mutex, semaphore, or other object for
> which a futex wait arrives "very late" due to scheduling. It has
> nothing to do with the destruction of cond vars.

Hm, but then we have a problem on the side that has this late wait,
that is an access to a dead object. So the UB is there, in that thread
that is doing the wait. (Suppose it is just threads and not processes,
that would even be more complicated.) That spurious wakeup that you
are talking about is a consequence of UB.

good night

Jens

-- 
:: INRIA Nancy Grand Est ::: AlGorille ::: ICube/ICPS :::
:: ::::::::::::::: office Strasbourg : +33 368854536   ::
:: :::::::::::::::::::::: gsm France : +33 651400183   ::
:: ::::::::::::::: gsm international : +49 15737185122 ::
:: http://icube-icps.unistra.fr/index.php/Jens_Gustedt ::



[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 198 bytes --]

  reply	other threads:[~2014-08-06 22:43 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-04  9:30 C threads, v3.0 Jens Gustedt
2014-08-04  9:33 ` Jens Gustedt
2014-08-04 14:50 ` Rich Felker
2014-08-04 16:48   ` Jens Gustedt
2014-08-04 17:06     ` Rich Felker
2014-08-04 22:16       ` Jens Gustedt
2014-08-04 22:36         ` Rich Felker
2014-08-06  3:52 ` Explaining cond var destroy [Re: [musl] C threads, v3.0] Rich Felker
2014-08-06  8:43   ` Jens Gustedt
2014-08-06  9:41     ` Jens Gustedt
2014-08-06 10:03       ` Rich Felker
2014-08-06 10:32         ` Jens Gustedt
2014-08-06 16:15           ` Rich Felker
2014-08-06 16:56             ` Jens Gustedt
2014-08-06 17:32               ` Rich Felker
2014-08-06 20:55                 ` Jens Gustedt
2014-08-06 22:04                   ` Rich Felker
2014-08-06 22:43                     ` Jens Gustedt [this message]
2014-08-06 23:15                       ` Rich Felker
2014-08-07  7:50                         ` Jens Gustedt
2014-08-07 10:52                           ` Szabolcs Nagy
2014-08-07 11:03                             ` Jens Gustedt
2014-08-07 16:13                           ` Rich Felker
2014-08-07 16:47                             ` Jens Gustedt
2014-08-07 17:25                               ` Rich Felker
2014-08-08  9:20                                 ` Jens Gustedt
2014-08-08 16:53                                   ` Rich Felker
2014-08-08 19:14                                   ` Rich Felker
2014-08-08 20:48                                     ` Rich Felker
2014-08-09  6:47                                       ` Jens Gustedt
2014-08-12  2:50                                         ` Rich Felker
2014-08-12  7:04                                           ` Jens Gustedt
2014-08-12 16:01                                             ` Rich Felker
2014-08-12 19:09                                               ` Jens Gustedt
2014-08-12 21:18                                                 ` Rich Felker
2014-08-13  6:43                                                   ` Jens Gustedt
2014-08-13  7:19                                                     ` Jens Gustedt
2014-08-06  9:50     ` Rich Felker

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=1407365015.24324.334.camel@eris.loria.fr \
    --to=jens.gustedt@inria.fr \
    --cc=musl@lists.openwall.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.
Code repositories for project(s) associated with this public inbox

	https://git.vuxu.org/mirror/musl/

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 NNTP newsgroup(s).