Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 23 Jan 2002 06:45:47 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 23 Jan 2002 06:45:37 -0500 Received: from pizda.ninka.net ([216.101.162.242]:12416 "EHLO pizda.ninka.net") by vger.kernel.org with ESMTP id ; Wed, 23 Jan 2002 06:45:25 -0500 Date: Wed, 23 Jan 2002 03:44:11 -0800 (PST) Message-Id: <20020123.034411.71089598.davem@redhat.com> To: manfred@colorfullife.com, masp0008@stud.uni-saarland.de Cc: drobbins@gentoo.org, linux-kernel@vger.kernel.org Subject: Re: Athlon/AGP issue update From: "David S. Miller" In-Reply-To: <3C4E9291.8DA0BD7F@stud.uni-saarland.de> In-Reply-To: <3C4E9291.8DA0BD7F@stud.uni-saarland.de> X-Mailer: Mew version 2.1 on Emacs 21.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Studierende der Universitaet des Saarlandes Date: Wed, 23 Jan 2002 10:38:09 +0000 Then "nopentium" only works by chance: I assume that speculative operations do not walk the page tables, thus the probability that a valid TLB entry is found for the GART mapped page is slim. But if there is an entry, then the corruption would still occur. This isn't true. The speculative store won't get data into the cache if there is a TLB miss. 4MB pages map the GART pages and "other stuff", ie. memory used by other subsystems, user pages and whatever else. This is the only way the bug can be thus triggered for kernel mappings, which is why turning off 4MB pages fixes this part. The only unresolved bit is the fact that we map these GART pages cacheable into user space. That ought to cause the problem too. - 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/