From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25474 invoked by alias); 21 Nov 2008 01:34:19 -0000 Received: (qmail 25443 invoked by uid 22791); 21 Nov 2008 01:34:18 -0000 X-Spam-Check-By: sourceware.org Received: from mtagate2.de.ibm.com (HELO mtagate2.de.ibm.com) (195.212.17.162) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 21 Nov 2008 01:33:32 +0000 Received: from d12nrmr1607.megacenter.de.ibm.com (d12nrmr1607.megacenter.de.ibm.com [9.149.167.49]) by mtagate2.de.ibm.com (8.13.1/8.13.1) with ESMTP id mAL1XUUr007906 for ; Fri, 21 Nov 2008 01:33:30 GMT Received: from d12av02.megacenter.de.ibm.com (d12av02.megacenter.de.ibm.com [9.149.165.228]) by d12nrmr1607.megacenter.de.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id mAL1XTE63543214 for ; Fri, 21 Nov 2008 02:33:29 +0100 Received: from d12av02.megacenter.de.ibm.com (loopback [127.0.0.1]) by d12av02.megacenter.de.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id mAL1XTIH010878 for ; Fri, 21 Nov 2008 02:33:29 +0100 Received: from tuxmaker.boeblingen.de.ibm.com (tuxmaker.boeblingen.de.ibm.com [9.152.85.9]) by d12av02.megacenter.de.ibm.com (8.12.11.20060308/8.12.11) with SMTP id mAL1XTSF010875; Fri, 21 Nov 2008 02:33:29 +0100 Message-Id: <200811210133.mAL1XTSF010875@d12av02.megacenter.de.ibm.com> Received: by tuxmaker.boeblingen.de.ibm.com (sSMTP sendmail emulation); Fri, 21 Nov 2008 02:33:29 +0100 Subject: Re: [rfc] Handle broken CFI for signal trampolines in libc on amd64-linux To: drow@false.org (Daniel Jacobowitz) Date: Fri, 21 Nov 2008 18:12:00 -0000 From: "Ulrich Weigand" Cc: gdb-patches@sourceware.org In-Reply-To: <20081120235151.GA12123@caradoc.them.org> from "Daniel Jacobowitz" at Nov 20, 2008 06:51:51 PM X-Mailer: ELM [version 2.5 PL2] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2008-11/txt/msg00573.txt.bz2 Daniel Jacobowitz wrote: > On Fri, Nov 21, 2008 at 12:38:11AM +0100, Ulrich Weigand wrote: > > Unfortunately even if I use the dwarf_signal_frame_p hook to have the > > DWARF-2 sniffer recognize a SIGTRAMP_FRAME, it still doesn't work as > > the __restore_rt CFI (at least in my glibc) only describes the unwind > > effects as if it were a regular function, without taking into account > > the restoring of registers by the sigreturn system call. > > What version of glibc is this? It was fixed two years ago this month: Well, it's the system glibc of my openSUSE 10.2 install (based on a 2006-10-12 glibc-2.5 snapshot), which is indeed somewhat over two years old. I guess I could update to a more recent distro one of these days ... Anyway, while it is certainly good that this is fixed, I'm still wondering why we should rely on that when we have a hard-coded sigtramp detector that should be working just fine under any circumstances. Bye, Ulrich -- Dr. Ulrich Weigand GNU Toolchain for Linux on System z and Cell BE Ulrich.Weigand@de.ibm.com