From owner-freebsd-hackers Tue Jul 20 10:56:55 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [209.157.86.2]) by hub.freebsd.org (Postfix) with ESMTP id B0DA8153B0 for ; Tue, 20 Jul 1999 10:56:51 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.3/8.9.1) id KAA06018; Tue, 20 Jul 1999 10:54:46 -0700 (PDT) (envelope-from dillon) Date: Tue, 20 Jul 1999 10:54:46 -0700 (PDT) From: Matthew Dillon Message-Id: <199907201754.KAA06018@apollo.backplane.com> To: Bob Bishop Cc: "Kelly Yancey" , , Subject: Re: RE: Overcommit and calloc() References: Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :Hi, : :At 1:28 pm -0400 20/7/99, Kelly Yancey wrote: :>[...] :> On recent thought though, I seem to recall having read in the 4.4BSD :>Daemon book that having the kernel zero memory is not the preferred :>practice, but present because when they tried to stop many progrems dies :>which assumed memory was initialized to zero. : :Handing out unzeroed memory is a potential security hole. : :-- :Bob Bishop (0118) 977 4017 international code +44 118 :rb@gid.co.uk fax (0118) 989 4254 between 0800 and 1800 UK It should also be noted that unless your system is entirely cpu-bound, there is no cost to the kernel to zero memory because it pre-zero's pages in its idle loop. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message