From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 15 Jan 2001 02:15:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 15 Jan 2001 02:14:52 -0500 Received: from slc111.modem.xmission.com ([166.70.9.111]:62732 "EHLO flinx.biederman.org") by vger.kernel.org with ESMTP id ; Mon, 15 Jan 2001 02:14:46 -0500 To: Ralf Baechle Cc: Russell King , riel@nl.linux.org, andrea@suse.de (Andrea Arcangeli), linux-kernel@vger.kernel.org Subject: Re: Subtle MM bug In-Reply-To: <200101122111.f0CLBhL10716@flint.arm.linux.org.uk> <20010115005610.E1656@bacchus.dhis.org> From: ebiederm@xmission.com (Eric W. Biederman) Date: 14 Jan 2001 23:59:23 -0700 In-Reply-To: Ralf Baechle's message of "Mon, 15 Jan 2001 00:56:10 -0200" Message-ID: User-Agent: Gnus/5.0803 (Gnus v5.8.3) Emacs/20.5 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ralf Baechle writes: > On Fri, Jan 12, 2001 at 09:11:43PM +0000, Russell King wrote: > > > Eric W. Biederman writes: > > > Hmm. I would think that increasing the logical page size in the kernel > > > would be the trivial way to handle virtual aliases. (i.e.) with a large > > > enough page size you can't actually have a virtual alias. > > > > There are types of caches out there that no matter how large the page size, > > you will always have alias issues. These are ones where the cache lines > > are indexed independent of virtual address (and therefore can have funny > > cache line replacement algorithms). > > > > And yes, you guessed which processor has it. ;) Odd. Does this affect correctness? > I recently spoke with some CPU architecture researcher at some university > about cache architectures; I suspect in the near future we'll see more > funny cache indexing and replacment algorithems ... But I doubt many of those will run incorrectly if just less efficiently if the OS doesn't help you avoid aliases. Eric - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/