From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754346AbYIPRTT (ORCPT ); Tue, 16 Sep 2008 13:19:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751203AbYIPRTJ (ORCPT ); Tue, 16 Sep 2008 13:19:09 -0400 Received: from gw.goop.org ([64.81.55.164]:58521 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751186AbYIPRTJ (ORCPT ); Tue, 16 Sep 2008 13:19:09 -0400 Message-ID: <48CFEA8C.3020703@goop.org> Date: Tue, 16 Sep 2008 10:19:08 -0700 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Michael Tokarev CC: linux-kernel@vger.kernel.org Subject: Re: PARAVIRT_GUEST bug? [was: Stable regression: usb-storage is stuck in 2.6.26.5] References: <20080913122143.4B13B908E@gandalf.tls.msk.ru> <48CBB626.4050300@msgid.tls.msk.ru> <48CF6A45.3010204@msgid.tls.msk.ru> In-Reply-To: <48CF6A45.3010204@msgid.tls.msk.ru> X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Michael Tokarev wrote: > Michael Tokarev wrote: > > [usb-storage hangs on asus M2NPV-VM (nVidia GeForce 6150/nForce 430) > motherboard with latest bios] > >> Ok, it turned out to be pretty.. interesting. >> >> It's not a regression within -stable kernel series. The problem >> happens when BOTH are true: >> >> - using latest BIOS for this mobo (1401), AND >> - enabling KVM_GUEST in kernel. >> >> The only difference in my kernel config between .1 and .5 was >> to enable KVM_GUEST and KVM_CLOCK, and also I2C_HELPER_AUTO >> which was added by kernel update. >> >> Going with previous BIOS (1201) OR disabling PARAVIRT_GUEST >> fixes the problem. I'll try to figure out which config >> option is at problem here. > > After seeing similar situation on another motherboard, I > become curious. > > Here's the result: M3A78-EM motherboard (also from Asus), > AMD780G/SB700 etc. Updating to one of the latest bios > makes the system unbootable. Kernel hangs on boot right > after displaying > > SLUB: Genslabs=12, HWalign=64, Order=0-1, MinObjects=4, CPUs=2, Nodes=1 > > Reverting to the older BIOS or disabling PARAVIRT_GUEST in kernel > fixes this (turning off KVM_GUEST isn't enough), and kernel happily > boots further, with next line being > > hpet clockevent registered > ... > > Reportedly, another Asus motherboard (M2N-SLI DELUXE) also hangs > with new BIOS and KVM_GUEST optimizations turned on, but not on > older BIOS. > > So it's quite.. funny. At least SOME latest BIOSes from Asustec, > together with PARAVIRT_GUEST, -- a problem. Don't do either of > those, and it's all ok. > > The question is if Asus introduced the same bug in quite.. some > of their recent BIOSes, or PARAVIRT_GUEST code is somehow buggy > and the bug is exposed by new BIOS code. > > Any hints on this? ;) PARAVIRT_GUEST doesn't enable anything by itself; it just makes other config options appear. What other config options are you enabling? That is, what's the diff between a working and a non-working .config? J