From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Tue, 17 Jul 2007 11:14:33 +0100 (BST) Received: from localhost.localdomain ([127.0.0.1]:31434 "EHLO dl5rb.ham-radio-op.net") by ftp.linux-mips.org with ESMTP id S20021425AbXGQKOb (ORCPT ); Tue, 17 Jul 2007 11:14:31 +0100 Received: from denk.linux-mips.net (denk.linux-mips.net [127.0.0.1]) by dl5rb.ham-radio-op.net (8.14.1/8.13.8) with ESMTP id l6HAERmc005488; Tue, 17 Jul 2007 11:14:28 +0100 Received: (from ralf@localhost) by denk.linux-mips.net (8.14.1/8.14.1/Submit) id l6HAEQcq005487; Tue, 17 Jul 2007 11:14:26 +0100 Date: Tue, 17 Jul 2007 11:14:26 +0100 From: Ralf Baechle To: Sergey Rogozhkin Cc: Linux MIPS List , "Gleb O. Raiko" , Kumba Subject: Re: O2 RM7000 Issues Message-ID: <20070717101426.GA4759@linux-mips.org> References: <4687DCE2.8070302@gentoo.org> <468825BE.6090001@gmx.net> <50451.70.107.91.207.1183381723.squirrel@webmail.wesleyan.edu> <20070704152729.GA2925@linux-mips.org> <20070704192208.GA7873@linux-mips.org> <469C8600.7090208@niisi.msk.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <469C8600.7090208@niisi.msk.ru> User-Agent: Mutt/1.5.14 (2007-02-12) Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 15788 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: ralf@linux-mips.org Precedence: bulk X-list: linux-mips On Tue, Jul 17, 2007 at 01:04:00PM +0400, Sergey Rogozhkin wrote: > Are you really sure RM7000 has this bug? Workaround mentioned above > breaks gcc signal frame unwinding mechanism: it search for sigcontext > struct at fixed offset from signal trampoline. Sigh. Yes, I am certain - this is information right from the CPU designers. When I did modify the signal frame for PMC's E9000 core I knew some software such as debuggers was likely to break, so I was careful to only use the mechanism if absolutly necessary that is on E9000 cores. The problem semmed to strike rather frequently on E9000 but there had been no reports of application crashes matching the problem's fingerprint on RM7000 so the issue felt as if it was rather theoretical on RM7000. So I choose to not enable the workaround for RM7000 until recently. Ralf