From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755649AbYDAMMz (ORCPT ); Tue, 1 Apr 2008 08:12:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752992AbYDAMMs (ORCPT ); Tue, 1 Apr 2008 08:12:48 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:34293 "EHLO gprs189-60.eurotel.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752227AbYDAMMr (ORCPT ); Tue, 1 Apr 2008 08:12:47 -0400 Date: Tue, 1 Apr 2008 14:13:23 +0200 From: Pavel Machek To: Ingo Molnar Cc: Andi Kleen , kernel list Subject: Re: agpgart: when telling user you'll corrupt his data, at least do it at KERN_CRIT Message-ID: <20080401121323.GB12129@elf.ucw.cz> References: <20080328112507.GA10774@elf.ucw.cz> <20080328113528.GA8077@elte.hu> <20080328134451.GB4544@ucw.cz> <20080328141348.GE29218@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080328141348.GE29218@elte.hu> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 2008-03-28 15:13:48, Ingo Molnar wrote: > > * Pavel Machek wrote: > > > On Fri 2008-03-28 12:35:28, Ingo Molnar wrote: > > > > > > * Pavel Machek wrote: > > > > > > > IOMMU off means very bad stuff may happen, like data corruption on > > > > your hard drives. At least tells users this is serious... > > > > > > ouch. Please at minimum lets turn this into a panic(), but best would be > > > to trim memory in this case, hm? > > > > Andi tells me we already fallback to swiotlb, so messages are not on > > wrong loglevel; they contain confusing/obsolete text. > > yes that is the theory - but how did your disk get corrupted in > practice? ;-) Well, if you try suspend/resume, without iommu suspend/resume support (which is not there in some cases), you get nasty data corruption. ("PCI DMA will does not work"). Then, I saw [obsolete] printk(KERN_ERR) that told me that PCI DMA will not work, and happily continued to boot. I'll fix the messages. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html