From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH] KVM: x86: Don't deliver PIC interrupts to disabled APICs - v2 Date: Wed, 22 Oct 2008 17:09:41 +0200 Message-ID: <48FF4235.6020908@siemens.com> References: <48FC4671.90409@siemens.com> <48FC7435.4020707@siemens.com> <48FF33C9.40106@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: kvm-devel , "Yang, Sheng" To: Avi Kivity Return-path: Received: from gecko.sbs.de ([194.138.37.40]:18336 "EHLO gecko.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751670AbYJVPKD (ORCPT ); Wed, 22 Oct 2008 11:10:03 -0400 In-Reply-To: <48FF33C9.40106@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Avi Kivity wrote: > Jan Kiszka wrote: >> [ taking Sheng's comments into account ] >> >> The logic of kvm_apic_accept_pic_intr has a minor, practically hardly >> relevant incorrectness: PIC interrupts are still delivered even if the >> APIC of VPU0 (BSP) is disabled. This does not comply with the Virtual >> Wire mode according to the Intel MP spec. >> > > This breaks Windows XP with the Standard PC HAL, so I am unapplying this > patch. Hmm, this points to either an APIC setup or BIOS bug. To my understanding, the Standard PC HAL should not fiddle with the APIC, so what the BIOS leaves behind should counts. But I think I found no traces of APIC manipulation in rombios32.c. Jan -- Siemens AG, Corporate Technology, CT SE 2 Corporate Competence Center Embedded Linux