From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Custom BIOS supported size Date: Mon, 04 May 2009 17:31:43 +0300 Message-ID: <49FEFC4F.4090109@redhat.com> References: <1241384925.26848.10.camel@hyperion> <49FEF23E.3020105@redhat.com> <1241446175.30017.35.camel@hyperion> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org To: Cristi Magherusan Return-path: Received: from mx2.redhat.com ([66.187.237.31]:48048 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751568AbZEDOc0 (ORCPT ); Mon, 4 May 2009 10:32:26 -0400 In-Reply-To: <1241446175.30017.35.camel@hyperion> Sender: kvm-owner@vger.kernel.org List-ID: Cristi Magherusan wrote: > On Mon, 2009-05-04 at 16:48 +0300, Avi Kivity wrote: > >> Cristi Magherusan wrote: >> >>> Hello, >>> >>> Which is the maximum size supported for a custom BIOS image(eg. >>> coreboot-based)? I tried some 256K coreboot BIOS images and seemed to >>> work fine, but it blowed up with a 3MB image (which by the way works on >>> qemu just fine). >>> >>> >> 256K is the maximum with kvm. It can easily be increased, but we need a >> small kernel change on Intel to store the real-mode TSS. >> >> >> > Hi Avi, > > Thanks for your answer. What would be the upper bound up to which we can > extend it? May I somehow help in getting this done? > I don't know all the places; check the setup code in hw/pc.c. Also look at the call to KVM_SET_TSS_ADDR and move it somewhere where it won't clash (right now it's at 4GB-256K). -- Do not meddle in the internals of kernels, for they are subtle and quick to panic.