From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1JeqKI-0001Us-K4 for qemu-devel@nongnu.org; Thu, 27 Mar 2008 07:31:22 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1JeqKF-0001T1-Bw for qemu-devel@nongnu.org; Thu, 27 Mar 2008 07:31:22 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1JeqKF-0001Sm-6P for qemu-devel@nongnu.org; Thu, 27 Mar 2008 07:31:19 -0400 Received: from cerber.ds.pg.gda.pl ([153.19.208.18]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1JeqKE-00050B-Sx for qemu-devel@nongnu.org; Thu, 27 Mar 2008 07:31:19 -0400 Date: Thu, 27 Mar 2008 11:29:36 +0000 (GMT) From: "Maciej W. Rozycki" In-Reply-To: <47EB586E.3090002@qumranet.com> Message-ID: References: <12065794361493-git-send-email-gcosta@redhat.com> <47EB586E.3090002@qumranet.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Subject: [Qemu-devel] Re: [PATCH] ignore reads to the EOI register. Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Avi Kivity Cc: kvm-devel@lists.sourceforge.net, glommer@gmail.com, qemu-devel@nongnu.org, Glauber Costa On Thu, 27 Mar 2008, Avi Kivity wrote: > Applied, but perhaps a patch to linux to avoid reads to write-only registers > is needed as well. Linux performs reads to all registers written including this one deliberately using an RMW cycle to avoid triggering an erratum in some early Pentium integrated APICs. Obviously it does not matter for most of the world as the workaround is build-time conditional, but you'll get it if you build a generic "runs everywhere" kernel. Maciej