Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753192Ab3CKOM5 (ORCPT ); Mon, 11 Mar 2013 10:12:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:9754 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752658Ab3CKOMz (ORCPT ); Mon, 11 Mar 2013 10:12:55 -0400 Date: Mon, 11 Mar 2013 16:12:52 +0200 From: Gleb Natapov To: Jan Kiszka Cc: Paolo Bonzini , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , "mtosatti@redhat.com" Subject: Re: [PATCH] x86: kvm: reset the bootstrap processor when it gets an INIT Message-ID: <20130311141252.GQ31619@redhat.com> References: <20130311102852.GE31619@redhat.com> <513DBF45.9030803@redhat.com> <20130311115144.GG31619@redhat.com> <513DDCC2.9070807@redhat.com> <20130311135441.GN31619@redhat.com> <513DE3C4.5000503@siemens.com> <20130311140503.GO31619@redhat.com> <513DE4DA.4050009@siemens.com> <20130311140925.GP31619@redhat.com> <513DE5E5.1080402@siemens.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <513DE5E5.1080402@siemens.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1566 Lines: 37 On Mon, Mar 11, 2013 at 03:10:45PM +0100, Jan Kiszka wrote: > On 2013-03-11 15:09, Gleb Natapov wrote: > > On Mon, Mar 11, 2013 at 03:06:18PM +0100, Jan Kiszka wrote: > >> On 2013-03-11 15:05, Gleb Natapov wrote: > >>> On Mon, Mar 11, 2013 at 03:01:40PM +0100, Jan Kiszka wrote: > >>>>> We are not moving away from mp_state, we are moving away from using > >>>>> mp_state for signaling because with nested virt INIT does not always > >>>>> change mp_state, not only that it can change mp_state long after signal > >>>>> is received after vmx off is done. > >>>> > >>>> Right. > >>>> > >>>> BTW, for that to happen, we will also need to influence the INIT level. > >>>> Unless I misread the spec, INIT is blocked while in root mode, and if > >>>> you deassert INIT before leaving root (vmxoff, vmenter), nothing > >>>> actually happens. So what matters is the INIT signal level at the exit > >>>> of root mode. > >>>> > >>> You are talking about INIT# signal received via CPU pin, right? I think > >>> INIT send by IPI cannot go away. > >> > >> Why shouldn't it? Besides edge, there is also level-triggered INIT. > >> > > OK, so level-triggered INIT can be de-asserted what about edge triggered > > one? :) > > It should be lost while in root mode. > Ah, that's great. Removes some potential complications. -- Gleb. -- 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/