From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] KVM: mark segments accessed on HW task switch Date: Mon, 25 Jan 2010 13:12:36 +0200 Message-ID: <4B5D7CA4.5070605@redhat.com> References: <20100125100104.GA4609@redhat.com> <4B5D7B9D.7080401@redhat.com> <20100125111109.GA8483@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: mtosatti@redhat.com, kvm@vger.kernel.org To: Gleb Natapov Return-path: Received: from mx1.redhat.com ([209.132.183.28]:35013 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752668Ab0AYLMh (ORCPT ); Mon, 25 Jan 2010 06:12:37 -0500 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o0PBCbZa011207 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 25 Jan 2010 06:12:37 -0500 In-Reply-To: <20100125111109.GA8483@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 01/25/2010 01:11 PM, Gleb Natapov wrote: > On Mon, Jan 25, 2010 at 01:08:13PM +0200, Avi Kivity wrote: > >> On 01/25/2010 12:01 PM, Gleb Natapov wrote: >> >>> On HW task switch newly loaded segments should me marked as accessed. >>> >>> @@ -4775,6 +4766,11 @@ int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, >>> kvm_seg.unusable = 1; >>> >>> kvm_set_segment(vcpu,&kvm_seg, seg); >>> + if (selector&& !kvm_seg.unusable&& kvm_seg.s) { >>> + /* mark segment as accessed */ >>> + seg_desc.type |= 1; >>> + save_guest_segment_descriptor(vcpu, selector,&seg_desc); >>> + } >>> return 0; >>> } >>> >> What about an error return from s_g_s_d? >> >> > What can or should we do about it? > > If -EFAULT, propagate to userspace. -- error compiling committee.c: too many arguments to function