From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH] extboot: don't use interrupt vectors $0x2b and $0x2c Date: Tue, 22 Jul 2008 10:31:42 +0300 Message-ID: <48858CDE.3020205@qumranet.com> References: <1216405379-5550-1-git-send-email-hpa@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Anthony Liguori , kvm@vger.kernel.org To: "H. Peter Anvin" Return-path: Received: from il.qumranet.com ([212.179.150.194]:39773 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750964AbYGVHbp (ORCPT ); Tue, 22 Jul 2008 03:31:45 -0400 In-Reply-To: <1216405379-5550-1-git-send-email-hpa@zytor.com> Sender: kvm-owner@vger.kernel.org List-ID: H. Peter Anvin wrote: > extboot's use of interrupt vectors $0x2b and $0x2c is unsafe, as these > interrupt vectors fall in the OS-use range (0x20-0x3f). Furthermore, > it's unnecessary: we can keep a local pointer instead of hooking > another interrupt as long as we can write to our own segment. > > Make the extboot segment writable, and use local variables to hold the > old link pointers. > > If this turns out to cause problems, we should probably switch to > using vectors in the 0xc0-0xef range, and/or other BIOS-reserved > memory. > > Applied, thanks (as two patches). -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.