From owner-freebsd-stable@FreeBSD.ORG Sun May 14 18:54:01 2006 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DD25616A418 for ; Sun, 14 May 2006 18:54:01 +0000 (UTC) (envelope-from uspoerlein@gmail.com) Received: from nf-out-0910.google.com (nf-out-0910.google.com [64.233.182.191]) by mx1.FreeBSD.org (Postfix) with ESMTP id 00B4B43D48 for ; Sun, 14 May 2006 18:53:57 +0000 (GMT) (envelope-from uspoerlein@gmail.com) Received: by nf-out-0910.google.com with SMTP id y25so1314nfb for ; Sun, 14 May 2006 11:53:57 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:date:from:to:cc:subject:message-id:mail-followup-to:references:mime-version:content-type:content-disposition:in-reply-to; b=iM3lnMxzZ1sC7f4TooWeby9y4sZ/IkMl8F8VjPx9IMgfr278d5+RB3BOzFtCin+5eLhCkPSLviMlulg9AMPbl+C6rgSqi2OHi74vktrEWJSObxPt4H8dTmZkLhNW7U58qXPeDfS7tfqRB4Lqnan7aeJiTSJDV1xRkz8uSN/KKH8= Received: by 10.48.222.9 with SMTP id u9mr1450475nfg; Sun, 14 May 2006 11:47:24 -0700 (PDT) Received: from roadrunner.q.local ( [217.185.114.67]) by mx.gmail.com with ESMTP id x1sm1057182nfb.2006.05.14.11.47.18; Sun, 14 May 2006 11:47:23 -0700 (PDT) Received: from roadrunner.q.local (localhost [127.0.0.1]) by roadrunner.q.local (8.13.6/8.13.6) with ESMTP id k4EIj8jP004879; Sun, 14 May 2006 20:45:11 +0200 (CEST) (envelope-from uspoerlein@gmail.com) Received: (from q@localhost) by roadrunner.q.local (8.13.6/8.13.6/Submit) id k4E9Xcvr002095; Sun, 14 May 2006 11:33:38 +0200 (CEST) (envelope-from uspoerlein@gmail.com) Date: Sun, 14 May 2006 11:33:38 +0200 From: Ulrich Spoerlein To: "Matthew D. Fuller" Message-ID: <20060514093338.GB1025@roadrunner.informatik.uni-wuerzburg.de> Mail-Followup-To: "Matthew D. Fuller" , Kris Kennaway , freebsd-stable@FreeBSD.org References: <20060427181226.GA66431@xor.obsecurity.org> <20060428122448.K57436@atlantis.atlantis.dp.ua> <20060428182818.GA10410@xor.obsecurity.org> <20060512161836.R75964@atlantis.atlantis.dp.ua> <20060513020051.GB18438@xor.obsecurity.org> <20060513084236.W74146@atlantis.atlantis.dp.ua> <20060513143740.GA46313@xor.obsecurity.org> <20060513155232.GF3874@over-yonder.net> <20060513155826.GA47324@xor.obsecurity.org> <20060513160337.GG3874@over-yonder.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ncSAzJYg3Aa9+CRW" Content-Disposition: inline In-Reply-To: <20060513160337.GG3874@over-yonder.net> Cc: freebsd-stable@freebsd.org, Kris Kennaway Subject: Re: INVARIANTS (was Re: RELENG_4 -> 5 -> 6: significant performance regression) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 14 May 2006 18:54:03 -0000 --ncSAzJYg3Aa9+CRW Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Matthew D. Fuller wrote: > On Sat, May 13, 2006 at 11:58:26AM -0400 I heard the voice of > Kris Kennaway, and lo! it spake thus: > >=20 > > FYI, INVARIANTS adds checks but does not (is not supposed to) divert > > code paths. >=20 > It does at least in UMA; it does a lot of bzero()/NULL'ing out of > memory, which might hide later uninitialized-use bugs that could bite > you without it Shouldn't it write something like 0xdeadc0de or 0x0d0d0d0d to memory -- like user-land memory debugging tools do -- to catch read-before-write bugs? Ulrich Spoerlein --=20 PGP Key ID: 20FEE9DD Encrypted mail welcome! Fingerprint: AEC9 AF5E 01AC 4EE1 8F70 6CBD E76E 2227 20FE E9DD Which is worse: ignorance or apathy? Don't know. Don't care. --ncSAzJYg3Aa9+CRW Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (FreeBSD) iD8DBQFEZvly524iJyD+6d0RAlwyAKCMHI4J21YtgRBRsduARhRidFtLDACgpAkr wvDec/cNcg0T0v/WrQ9ANto= =6dv7 -----END PGP SIGNATURE----- --ncSAzJYg3Aa9+CRW--