From mboxrd@z Thu Jan 1 00:00:00 1970 From: OGAWA Hirofumi Subject: Re: nmi is broken? Date: Tue, 03 May 2011 22:25:10 +0900 Message-ID: <87hb9blxvt.fsf@devron.myhome.or.jp> References: <87sjtbe7fz.fsf@devron.myhome.or.jp> <877hak1t1s.fsf@devron.myhome.or.jp> <4DB3C6D3.9040703@redhat.com> <4DB41696.6060606@web.de> <4DB7DA11.8040503@redhat.com> <871v0njhab.fsf@devron.myhome.or.jp> <4DB93A6D.3010703@redhat.com> <87sjt2ij8b.fsf@devron.myhome.or.jp> <87k4eeihdu.fsf@devron.myhome.or.jp> <87mxj7urb0.fsf@devron.myhome.or.jp> <4DBE6F6B.6090103@redhat.com> <8739kxgoo0.fsf@devron.myhome.or.jp> <4DBFCC81.9080401@redhat.com> <4DBFD3F5.8020406@redhat.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Jan Kiszka , kvm@vger.kernel.org To: Avi Kivity Return-path: Received: from mail.parknet.co.jp ([210.171.160.6]:51085 "EHLO mail.parknet.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751022Ab1ECNZP (ORCPT ); Tue, 3 May 2011 09:25:15 -0400 In-Reply-To: <4DBFD3F5.8020406@redhat.com> (Avi Kivity's message of "Tue, 03 May 2011 13:07:49 +0300") Sender: kvm-owner@vger.kernel.org List-ID: Avi Kivity writes: > On 05/03/2011 12:36 PM, Avi Kivity wrote: >> >>> I don't know about live migration of kvm. If we said the wiring is like >>> figure 5-2, what is required for the live migration? It was required >>> only if IMCR was required? >> >> The issue with live migration is that we can't change the running >> configuration while the system is running, like adding the IMCR or >> changing the wiring. The hardware will be programmed for the old >> configuration and will likely fail with the new one. For example, the >> current wiring has the PIT output wired to PIC IRQ0 and IOAPIC INTI0; >> we need to change it to IOAPIC INTI2 instead. >> > > btw, I believe that the configuration currently implemented is legal > (it's similar to config 7 in table 5-2 of the mpspec); the only problem > is that it can't support the NMI watchdog through the I/O APIC trick, > yet we allow it through a hack. I'm confused a bit. "config 7 in table 5-2" says PIT output wired to IOAPIC INTIN2. So, we don't need to change it? > Something we can do is connect the 8259A output to the I/O APIC INTIN2; > it should be masked so live migration will continue to work. We just > have to make sure that the guest is able to find that it is connected there. 8259A INTR to IOAPIC INTIN2 sounds strange. Isn't it IOAPIC INTIN0? Thanks. -- OGAWA Hirofumi