Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030505AbXBZVU3 (ORCPT ); Mon, 26 Feb 2007 16:20:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933803AbXBZVU3 (ORCPT ); Mon, 26 Feb 2007 16:20:29 -0500 Received: from smtp.osdl.org ([65.172.181.24]:34593 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933800AbXBZVU2 (ORCPT ); Mon, 26 Feb 2007 16:20:28 -0500 Date: Mon, 26 Feb 2007 13:14:07 -0800 (PST) From: Linus Torvalds To: Rene Herman cc: Oleg Nesterov , Stephane Eranian , linux-kernel@vger.kernel.org Subject: Re: bug in kernel 2.6.21-rc1-git1: conventional floppy drive cannot be mounted without hanging up the whole system In-Reply-To: <45E3493C.1040706@gmail.com> Message-ID: References: <20070226180635.GA644@tv-sign.ru> <45E3493C.1040706@gmail.com> 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 Content-Length: 1569 Lines: 32 On Mon, 26 Feb 2007, Rene Herman wrote: > > Other than these two, ECP parallel ports are the other remaining users. > Now, even though on a machine that still has a parallel port it might usually > indeed be set to ECP in its BIOS; having anything attached to the port also > use it as such seems quite seldom. Well, if it's some kind of cache coherency problem (the same way much more modern CPU's have cache coherency issues with DMA during C3 sleep), then it's entirely possible that the normal ECP parallel port behaviour would never show it, since most people tend to use it for output only (yeah, I realize you can use it bidirectionally, but at least on old hardware it tends to be "talk AT printer" rather than "talk WITH printer". I frankly forget what hardware platforms had problems with the DMA thing, and what the exact behaviour even was (I think there was some possibility of corrupt data on the floppy). We also used to have the "nohlt" flag to turn off hlt entirely, and that was due to some other legacy issues, iirc. I seriously doubt we will ever see anybody who has this problem ever again, but on the other hand, I also seriously doubt that most modern machines even *have* a floppy drive any more, so I'd rather not even change it. It's just not worth even a miniscule risk.. Linus - 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/