From owner-svn-src-head@FreeBSD.ORG Wed Mar 6 23:16:18 2013 Return-Path: Delivered-To: svn-src-head@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 2ED5D8F7; Wed, 6 Mar 2013 23:16:18 +0000 (UTC) (envelope-from dwmalone@maths.tcd.ie) Received: from salmon.maths.tcd.ie (salmon.maths.tcd.ie [IPv6:2001:770:10:300::86e2:510b]) by mx1.freebsd.org (Postfix) with SMTP id 14BE8F56; Wed, 6 Mar 2013 23:16:16 +0000 (UTC) Received: from walton.maths.tcd.ie ([IPv6:2001:770:10:300::86e2:510a] helo=walton.maths.tcd.ie) by salmon.maths.tcd.ie with SMTP id ; 6 Mar 2013 23:16:14 +0000 (GMT) Received: by walton.maths.tcd.ie (Postfix, from userid 238) id 3769E7306E; Wed, 6 Mar 2013 23:16:13 +0000 (GMT) Date: Wed, 6 Mar 2013 23:16:13 +0000 From: David Malone To: Peter Grehan Subject: Re: svn commit: r247871 - head/usr.sbin/bhyve Message-ID: <20130306231613.GA5146@walton.maths.tcd.ie> References: <201303060728.r267SKP3018477@svn.freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201303060728.r267SKP3018477@svn.freebsd.org> User-Agent: Mutt/1.5.21 (2010-09-15) Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org, src-committers@FreeBSD.org X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Mar 2013 23:16:18 -0000 > + /* > + * We're just computing (a-b) in GF(216). > + ndesc = (unsigned)*hq->hq_avail_idx - (unsigned)hq->hq_cur_aidx; I think the comment here is wrong? Subtraction (and addition) in GF(2^16) is just xor of 16 bit numbers. You seem to actually be working in Z(2^16), where subtraction is normal subtraction mod 65536. David.