From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Williamson Subject: Re: [PATCH] Re: [PATCH] Std VGA Performance Date: Tue, 30 Oct 2007 10:40:58 -0600 Message-ID: <1193762458.31834.24.camel@bling> References: Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel , Robert Phillips , Ben Guthro , xen-ia64-devel List-Id: xen-devel@lists.xenproject.org On Tue, 2007-10-30 at 16:24 +0000, Keir Fraser wrote: > Yeah, hopefully that's a bug in the comment. I would expect 4-byte accesses > to be possible and be handled. As for 8-byte accesses, they can certainly > happen, why not? Unlikely at start of day, but once we're in x86/64 mode > there's no reason why not. Right, and it seems that the "quadword" handling is quite specific to timeoffset. It takes advantage of the fact that that there's no address and stuff some of the data in there. So, I think both 4 & 8 byte buffered mmio is likely broken right now on x86. Thanks, Alex -- Alex Williamson HP Open Source & Linux Org.