Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261564AbVEPNoO (ORCPT ); Mon, 16 May 2005 09:44:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261630AbVEPNoN (ORCPT ); Mon, 16 May 2005 09:44:13 -0400 Received: from cpu1185.adsl.bellglobal.com ([207.236.110.166]:9741 "EHLO mail.rtr.ca") by vger.kernel.org with ESMTP id S261564AbVEPNoI (ORCPT ); Mon, 16 May 2005 09:44:08 -0400 Message-ID: <4288A3A5.5010006@rtr.ca> Date: Mon, 16 May 2005 09:44:05 -0400 From: Mark Lord User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.7) Gecko/20050420 Debian/1.7.7-2 X-Accept-Language: en, en-us MIME-Version: 1.0 To: Gene Heskett Cc: linux-kernel@vger.kernel.org Subject: Re: Disk write cache (Was: Hyper-Threading Vulnerability) References: <1115963481.1723.3.camel@alderaan.trey.hu> <200505152156.18194.gene.heskett@verizon.net> <42880620.8000300@rtr.ca> <200505152308.04960.gene.heskett@verizon.net> In-Reply-To: <200505152308.04960.gene.heskett@verizon.net> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1034 Lines: 26 Gene Heskett wrote: > >>There's your clue. The drive LEDs normally reflect activity >>over the ATA bus (the cable!). If they're not on, then the drive >>isn't receiving data/commands from the host. > > That was my theory too Mark, but Jeff G. says its not a valid > indicator. So who's right? If the LEDs are connected to the controller on the motherboard, then they are a strict indication of activity over the cable between the drive and controller (if they function at all). But it is possible for software to leave those LEDs permanently in the "on" state, depending on the register sequence used. If the LEDs are on the drive itself, they may indicate transfers over the connector (cable) -- usually always the case -- or they could indicate transfers to/from the media. Cheers - 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/