From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: ludo@gnu.org (Ludovic =?iso-8859-1?Q?Court=E8s?=) Newsgroups: gmane.lisp.guile.bugs,gmane.lisp.guile.devel Subject: Re: [PATCH] fix for Re: crash in gc with upside-down stack Date: Fri, 14 Nov 2008 00:40:42 +0100 Message-ID: <87abc3yz2d.fsf@gnu.org> References: <3ae3aa420811131350v12ea6a6dj46f7cc59750d8469@mail.gmail.com> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: ger.gmane.org 1226619675 4969 80.91.229.12 (13 Nov 2008 23:41:15 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Thu, 13 Nov 2008 23:41:15 +0000 (UTC) Cc: guile-devel@gnu.org To: bug-guile@gnu.org Original-X-From: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Fri Nov 14 00:42:17 2008 Return-path: Envelope-to: guile-bugs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1L0lpI-0005Vz-9m for guile-bugs@m.gmane.org; Fri, 14 Nov 2008 00:42:16 +0100 Original-Received: from localhost ([127.0.0.1]:49897 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1L0loA-000563-9W for guile-bugs@m.gmane.org; Thu, 13 Nov 2008 18:41:06 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1L0lo5-00055y-Km for bug-guile@gnu.org; Thu, 13 Nov 2008 18:41:01 -0500 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1L0lo3-00055g-V0 for bug-guile@gnu.org; Thu, 13 Nov 2008 18:41:01 -0500 Original-Received: from [199.232.76.173] (port=59665 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1L0lo3-00055d-QS for bug-guile@gnu.org; Thu, 13 Nov 2008 18:40:59 -0500 Original-Received: from main.gmane.org ([80.91.229.2]:51833 helo=ciao.gmane.org) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1L0lo3-0006uL-NG for bug-guile@gnu.org; Thu, 13 Nov 2008 18:40:59 -0500 Original-Received: from list by ciao.gmane.org with local (Exim 4.43) id 1L0lnz-0004S0-RW for bug-guile@gnu.org; Thu, 13 Nov 2008 23:40:55 +0000 Original-Received: from reverse-83.fdn.fr ([80.67.176.83]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 13 Nov 2008 23:40:55 +0000 Original-Received: from ludo by reverse-83.fdn.fr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 13 Nov 2008 23:40:55 +0000 X-Injected-Via-Gmane: http://gmane.org/ Original-Followup-To: gmane.lisp.guile.bugs Original-Lines: 20 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: reverse-83.fdn.fr X-URL: http://www.fdn.fr/~lcourtes/ X-Revolutionary-Date: 24 Brumaire an 217 de la =?iso-8859-1?Q?R=E9volution?= X-PGP-Key-ID: 0xEA52ECF4 X-PGP-Key: http://www.fdn.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 821D 815D 902A 7EAB 5CEE D120 7FBA 3D4F EB1F 5364 X-OS: i686-pc-linux-gnu User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.3 (gnu/linux) Cancel-Lock: sha1:fWAi3FLep+WP8/5VdYWxobfQBWQ= X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-BeenThere: bug-guile@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Bug reports for GUILE, GNU's Ubiquitous Extension Language" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Errors-To: bug-guile-bounces+guile-bugs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.bugs:4095 gmane.lisp.guile.devel:7841 Archived-At: Hi, "Linas Vepstas" writes: > The patch below fixes a crash during garbage collection, where, during > the mark-stack phase, the top and bottom of the stack are found to be > in backwards order, typically because scm_with_guile() was called when > the stack is much shorter than when a thread was first guilified. That > is, the stack base pointer is stale, and can be inverted from the stack > top. If GC runs due to activity in some other thread, the stale base > pointer leads to the crash (as base-top is approximately 2^32 or 2^64). Good catch! I applied it, along with a test case that reproduced the problem: http://git.savannah.gnu.org/gitweb/?p=guile.git;a=commitdiff;h=cd1a1e47b5e781277560d9933a44e6aabd0c9c49 Thanks! Ludo'.