From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] KVM: VMX: Conditionally reload debug register 6 Date: Tue, 01 Sep 2009 14:53:43 +0300 Message-ID: <4A9D0B47.20805@redhat.com> References: <1251805232-16885-1-git-send-email-avi@redhat.com> <4A9D08D2.1020407@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , "kvm@vger.kernel.org" To: Jan Kiszka Return-path: Received: from mx1.redhat.com ([209.132.183.28]:8002 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753969AbZIALxp (ORCPT ); Tue, 1 Sep 2009 07:53:45 -0400 In-Reply-To: <4A9D08D2.1020407@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: On 09/01/2009 02:43 PM, Jan Kiszka wrote: > @@ -3731,7 +3732,8 @@ static void vmx_vcpu_run(struct kvm_vcpu *vcpu) >> | (1<< VCPU_EXREG_PDPTR)); >> vcpu->arch.regs_dirty = 0; >> >> - get_debugreg(vcpu->arch.dr6, 6); >> + if (vcpu->arch.switch_db_regs) >> + get_debugreg(vcpu->arch.dr6, 6); >> >> vmx->idt_vectoring_info = vmcs_read32(IDT_VECTORING_INFO_FIELD); >> if (vmx->rmode.irq.pending) >> > That reduces the emulation quality as vcpu->arch.switch_db_regs is only > set if some breakpoint is active while dr6 has its use also when that is > not the case). > True - there's the TF reason reporting bits. How about this then: - if !switch_db_regs, trap #DB - on #DB trap, copy DR6.BS and DR6.BT to vcpu->arch.dr6, and reinject the #DB ? -- error compiling committee.c: too many arguments to function