From owner-freebsd-arch Thu Apr 19 10:10:51 2001 Delivered-To: freebsd-arch@freebsd.org Received: from earth.backplane.com (earth-nat-cw.backplane.com [208.161.114.67]) by hub.freebsd.org (Postfix) with ESMTP id E205E37B424 for ; Thu, 19 Apr 2001 10:10:49 -0700 (PDT) (envelope-from dillon@earth.backplane.com) Received: (from dillon@localhost) by earth.backplane.com (8.11.2/8.11.2) id f3JHAka55437; Thu, 19 Apr 2001 10:10:46 -0700 (PDT) (envelope-from dillon) Date: Thu, 19 Apr 2001 10:10:46 -0700 (PDT) From: Matt Dillon Message-Id: <200104191710.f3JHAka55437@earth.backplane.com> To: Terry Lambert Cc: bde@zeta.org.au (Bruce Evans), tlambert@primenet.com (Terry Lambert), arch@FreeBSD.ORG Subject: Re: Found BAD BUG: squashed References: <200104191647.JAA02940@usr08.primenet.com> Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :Note that Bruce's fix doesn't addres the invariant stomping the :reference count, which makes checking for multiple frees :impossible. The only way to fix that is to move the cr_ref out :of the first two bytes. : : :I would still like a general reference counting mechanism, so :I could turn on overflow checking at runtime. : :As I said before, this is independent of whether the cred is :duplicated near overflow, or the count pushes the overflow off :to 4 billion (without preventing it). : : Terry Lambert I think we can safely move the ref counter to the end of the structure (and make it a u_int) after the 4.3 release, and if you want to have a KASSERT to test for 4-billion-overflow, that's fine with me too. I think being able to check for a double-free is a good idea. -Matt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message