From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 7761 invoked by alias); 31 Jul 2007 10:18:26 -0000 Received: (qmail 7752 invoked by uid 22791); 31 Jul 2007 10:18:26 -0000 X-Spam-Status: No, hits=-0.4 required=5.0 tests=AWL,BAYES_00,DK_POLICY_SIGNSOME,FORGED_RCVD_HELO,SPF_FAIL X-Spam-Check-By: sourceware.org Received: from sccrmhc13.comcast.net (HELO sccrmhc13.comcast.net) (204.127.200.83) by sourceware.org (qpsmtpd/0.31) with ESMTP; Tue, 31 Jul 2007 10:18:24 +0000 Received: from gateway.sf.frob.com (c-67-160-211-197.hsd1.ca.comcast.net[67.160.211.197]) by comcast.net (sccrmhc13) with ESMTP id <200707311018220130078ld7e>; Tue, 31 Jul 2007 10:18:22 +0000 Received: from magilla.localdomain (magilla.sf.frob.com [198.49.250.228]) by gateway.sf.frob.com (Postfix) with ESMTP id 31BD5357B; Tue, 31 Jul 2007 03:18:21 -0700 (PDT) Received: by magilla.localdomain (Postfix, from userid 5281) id 109AB4D04BA; Tue, 31 Jul 2007 03:18:14 -0700 (PDT) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Mark Wielaard Cc: frysk@sourceware.org Subject: Re: Problem with getExe and testInsertedBreakpoint In-Reply-To: Mark Wielaard's message of Tuesday, 31 July 2007 11:57:27 +0200 <1185875847.3653.60.camel@dijkstra.wildebeest.org> Emacs: Our Lady of Perpetual Garbage Collection Message-Id: <20070731101817.109AB4D04BA@magilla.localdomain> Date: Tue, 31 Jul 2007 10:18:00 -0000 X-IsSubscribed: yes Mailing-List: contact frysk-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Post: List-Help: , Sender: frysk-owner@sourceware.org X-SW-Source: 2007-q3/txt/msg00235.txt.bz2 > But we would still need to make sure that when we produce core files we > also include the BuildID. What the changed kernel does is easy to replicate. When you otherwise would have elided a segment and it's a private mapping (...p in 2nd column of /proc/pid/maps) at offset 0 (3rd column), check if its contents begin with "\177ELF". If so, don't elide the first page of that segment. > Is there any way to make the kernel know that the page can > be remerged again because all writes to it have been reversed? No. This is one of the benefits that would come from the "fancy VM tricks" future item (don't bother asking for details, there aren't any). Thanks, Roland