Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261885AbVCNUYq (ORCPT ); Mon, 14 Mar 2005 15:24:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261871AbVCNUYY (ORCPT ); Mon, 14 Mar 2005 15:24:24 -0500 Received: from mail.aknet.ru ([217.67.122.194]:57358 "EHLO mail.aknet.ru") by vger.kernel.org with ESMTP id S261856AbVCNUUv (ORCPT ); Mon, 14 Mar 2005 15:20:51 -0500 Message-ID: <4235F230.8000106@aknet.ru> Date: Mon, 14 Mar 2005 23:21:04 +0300 From: Stas Sergeev User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.3) Gecko/20041020 X-Accept-Language: ru, en-us, en MIME-Version: 1.0 To: Brian Gerst Cc: linux-os@analogic.com, Jakob Eriksson , Pavel Machek , Linux kernel , wine-devel@winehq.org Subject: Re: [patch] x86: fix ESP corruption CPU bug References: <42348474.7040808@aknet.ru> <20050313201020.GB8231@elf.ucw.cz> <4234A8DD.9080305@aknet.ru> <423518A7.9030704@aknet.ru> <4235AC0B.70507@vmlinux.org> <4235E4D5.5070506@didntduck.org> In-Reply-To: <4235E4D5.5070506@didntduck.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 997 Lines: 23 Hello. Brian Gerst wrote: >> Can you tell me how the invisible high-word (invisible in VM-86, and >> in real mode) could possibly harm something running in VM-86 or >> read-mode ??? I don't even think it's a BUG. If the transition >> into and out of VM-86 doesn't handle the fact that the high-word >> of the stack hasn't been used in VM-86, then that piece of code >> is bad (the SP isn't even the same stack, BTW). > Because even in 16-bit mode (real, vm86 or 16-bit protected) you can use > 32-bit instructions, with an operand and/or address size override > prefix. And the real problem is when the pure 32bit code is starting to use the 16bit stack for some strange reasons. Looks like the common technique for the early dos4gw -based apps... - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/