Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756462AbYHYJal (ORCPT ); Mon, 25 Aug 2008 05:30:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754685AbYHYJad (ORCPT ); Mon, 25 Aug 2008 05:30:33 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:44208 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753828AbYHYJad (ORCPT ); Mon, 25 Aug 2008 05:30:33 -0400 Date: Mon, 25 Aug 2008 11:30:20 +0200 From: Ingo Molnar To: Avi Kivity Cc: "Eric W. Biederman" , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [PATCH] Fix emergency_restart (sysrq-b) with kvm loaded on Intel hosts Message-ID: <20080825093020.GA5617@elte.hu> References: <1219655506-27418-1-git-send-email-avi@qumranet.com> <20080825091508.GC9114@elte.hu> <48B27AFE.3080704@qumranet.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <48B27AFE.3080704@qumranet.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1326 Lines: 37 * Avi Kivity wrote: > Ingo Molnar wrote: >> * Avi Kivity wrote: >> >> >>> Enabling Intel VT has the curious side effect whereby the INIT signal >>> is blocked. Rather than comment on the wisdom of this side effect, >>> this patch adds an emergency restart reboot notifier, and modifies >>> the kvm reboot notifier to disable VT on emergency reboot. >>> >> >> looks good to me - i was bitten by that problem on a testbox. >> > > I'm a little worried about making emergency restart more complex. > > Another thing that worries me is that emergency_restart() doesn't > reset the box -- it sends INIT. We could do better by using the ACPI > FADT reset register (hopefully that's connected to RESET). reboot was always a bit fragile - i think we should only do that if we find a box where the FADT reset works better than the first-wave approaches we try. > Which seems to be what we want? Maybe we should just try acpi_reboot() > before the other stuff. perhaps in a separate commit, for v2.6.28 at the earliest. Ingo -- 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/