Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755805AbYKCNe4 (ORCPT ); Mon, 3 Nov 2008 08:34:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755129AbYKCNes (ORCPT ); Mon, 3 Nov 2008 08:34:48 -0500 Received: from mx2.redhat.com ([66.187.237.31]:52021 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755138AbYKCNer (ORCPT ); Mon, 3 Nov 2008 08:34:47 -0500 Date: Mon, 3 Nov 2008 11:33:06 -0200 From: Eduardo Habkost To: Avi Kivity Cc: Ingo Molnar , Andrey Borzenkov , Avi Kivity , mingo@redhat.com, Andrew Morton , "Rafael J. Wysocki" , Linux Kernel Mailing List , "Eric W. Biederman" Subject: Re: [PATCH] Use BIOS reboot on Toshiba Portege 4000 Message-ID: <20081103133306.GZ23893@blackpad> References: <200810312118.45368.arvidjaar@mail.ru> <20081103090843.GI11730@elte.hu> <490ECC4D.9090704@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <490ECC4D.9090704@redhat.com> X-Fnord: you can see the fnord User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1670 Lines: 42 On Mon, Nov 03, 2008 at 12:02:53PM +0200, Avi Kivity wrote: > Ingo Molnar wrote: >>> Subject: [PATCH] Use BIOS reboot on Toshiba Portege 4000 >>> >>> From: Andrey Borzenkov >>> >>> After commit c7ffa6c26277b403920e2255d10df849bd613380 which defaults >>> to reboot via ACPI keyboard is dead on Toshiba Portege 4000 upon reboot. >>> Power off is required to revive it again. Add DMI entry to force BIOS >>> reboot method as it was before. >>> >>> Signed-off-by: Andrey Borzenkov >>> >> >> Avi, i expect more boxes to be affected by this bug, and the DMI >> solution just does not scale. >> >> So could we please disable VMX from the emergency-shutdown code >> instead of twiddling with the reboot method? >> >> Something like this might work as well: iff VMX is enabled, we just do >> smp_send_stop() (instead of skipping it) which should take care of >> this. >> > > There is already some code being worked on for kdump (which suffers from > the same symptoms), only kdump uses NMI IPIs for increased stopping > power. Eduardo, can you take a look at porting it to emergency reboot? We probably need to disable vmx on all CPUs, but emergency reboot skips native_smp_send_stop() (where we could hook a virt_disable call in). As relying on IPIs defeats the whole point of emergency_restart, a proper fix will need to use NMIs like the kdump code does. -- Eduardo -- 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/