From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH v2] KVM: x86: Fix guest debug across vcpu INIT reset Date: Sun, 23 Sep 2012 15:01:16 +0200 Message-ID: <505F081C.7050807@redhat.com> References: <505A1F1F.1010606@siemens.com> <505B006A.2030604@redhat.com> <505BE23F.5090200@web.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , kvm , "Roedel, Joerg" To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:20240 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753776Ab2IWNBW (ORCPT ); Sun, 23 Sep 2012 09:01:22 -0400 In-Reply-To: <505BE23F.5090200@web.de> Sender: kvm-owner@vger.kernel.org List-ID: On 09/21/2012 06:42 AM, Jan Kiszka wrote: > From: Jan Kiszka > > If we reset a vcpu on INIT, we so far overwrote dr7 as provided by > KVM_SET_GUEST_DEBUG, and we also cleared switch_db_regs unconditionally. > > Fix this by saving the dr7 used for guest debugging and calculating the > effective register value as well as switch_db_regs on any potential > change. This will change to focus of the set_guest_debug vendor op to > update_dp_bp_intercept. > > Found while trying to stop on start_secondary. > Thanks, applied. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.