Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758870Ab0BYCsU (ORCPT ); Wed, 24 Feb 2010 21:48:20 -0500 Received: from hera.kernel.org ([140.211.167.34]:55697 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758840Ab0BYCsS (ORCPT ); Wed, 24 Feb 2010 21:48:18 -0500 Message-ID: <4B85E745.2000904@kernel.org> Date: Thu, 25 Feb 2010 11:58:13 +0900 From: Tejun Heo User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.5) Gecko/20091130 SUSE/3.0.0-1.1.1 Thunderbird/3.0 MIME-Version: 1.0 To: Yuhong Bao CC: hancockrwd@gmail.com, david-b@pacbell.net, greg@kroah.com, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Subject: Re: [PATCH 2.6.34] ehci-hcd: add option to enable 64-bit DMA support References: <4B7CAF95.6020306@gmail.com> <20100218052223.GA13254@kroah.com> <51f3faa71002181633w1649a648s37ae73da342d0c3f@mail.gmail.com> <201002192139.46189.david-b@pacbell.net> <51f3faa71002192315ia84786eo1138bf9ab3417f2d@mail.gmail.com> <51f3faa71002231626q1eb62adeo660c282418f0e01@mail.gmail.com>,<4B85E038.20905@kernel.org> In-Reply-To: X-Enigmail-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Thu, 25 Feb 2010 02:48:13 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1141 Lines: 28 Hello, On 02/25/2010 11:41 AM, Yuhong Bao wrote: > >> gained. There just isn't much point in trying to enable a shiny new >> feature on an aging platform or technology. > You mean we should focus on enabling 64-bit DMA for USB 3.0 (xHCI)? Yeah, probably, in this context, but I was just making a general statement. Trying out a new feature which hasn't been used widely on old things doesn't go too well in many cases - the hw vendor and BIOS writer already moved on, people end up experiencing regressions on configurations which used to work fine and when that happens, new comers try out and find out it's broken in strange ways and when that happens they're much less likely to bother reporting and trying to get the problem fixed. And, most importantly, when things aren't used widely, that usually is for a reason - it just doesn't make that much of a difference. Thanks. -- tejun -- 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/