From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [PATCH 5/5] x86/HVM: don't setup an intercept handler for IO port 0xcf8 unconditionally Date: Wed, 13 Jan 2016 16:45:20 +0000 Message-ID: <56967F20.1010800@citrix.com> References: <1452688338-70075-1-git-send-email-roger.pau@citrix.com> <1452688338-70075-6-git-send-email-roger.pau@citrix.com> <56968BA902000078000C66BF@prv-mh.provo.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1aJOYb-0008Qy-7W for xen-devel@lists.xenproject.org; Wed, 13 Jan 2016 16:46:01 +0000 In-Reply-To: <56968BA902000078000C66BF@prv-mh.provo.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich , Paul Durrant , Roger Pau Monne Cc: xen-devel@lists.xenproject.org List-Id: xen-devel@lists.xenproject.org On 13/01/16 16:38, Jan Beulich wrote: >>>> On 13.01.16 at 13:32, wrote: >> Only intercept accesses to IO port 0xcf8 if there's at least one IOREQ >> server, otherwise it makes no sense since the only code that uses the value >> stored by hvm_access_cf8 is the IOREQ server. > Afaict an ioreq server could also attach subsequently - Paul? Indeed it can. The last-latched cfc/cf8 values should be accurate at that point. The intercept needs to stay. ~Andrew