From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: ATA support for 4k sector size Date: Thu, 26 Feb 2009 13:02:49 -0800 Message-ID: <49A70379.3050306@zytor.com> References: <1235600698-6446-1-git-send-email-matthew@wil.cx> <49A5CBF7.9000501@zytor.com> <20090226025043.GJ1363@mit.edu> <20090226030735.GA16891@parisc-linux.org> <49A6B604.1060702@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from terminus.zytor.com ([198.137.202.10]:53478 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751289AbZBZVEe (ORCPT ); Thu, 26 Feb 2009 16:04:34 -0500 In-Reply-To: Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: "Martin K. Petersen" Cc: Matthew Wilcox , Theodore Tso , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, sandeen@redhat.com Martin K. Petersen wrote: >>>>>> "hpa" == H Peter Anvin writes: > >>> Quick answer from one of my contacts. Desktop drives will indeed >>> ship with an alignment of 1(*). The alignment is hardwired at time >>> of manufacture and can't be changed. >>> > > hpa> Oh God. > > hpa> This is a disaster. > > Rationale being that modern Microsoft operating systems know how to > interpret the alignment bits. Legacy XP will work without changes > thanks to the shifted alignment. And Vista+ will do the right thing to > align partition 1 to what the drive reports. > > Also note that Windows only aligns the first partition. That's > something we need to be aware of when setting up dual boot systems. > Yeah, but all of this completely breaks the disk image abstraction, which is a very powerful paradigm. -hpa