From owner-freebsd-hackers Wed Apr 5 08:35:35 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id IAA22822 for hackers-outgoing; Wed, 5 Apr 1995 08:35:35 -0700 Received: from ref.tfs.com (ref.tfs.com [140.145.254.251]) by freefall.cdrom.com (8.6.10/8.6.6) with ESMTP id IAA22816 for ; Wed, 5 Apr 1995 08:35:34 -0700 Received: (from phk@localhost) by ref.tfs.com (8.6.8/8.6.6) id IAA08540; Wed, 5 Apr 1995 08:30:25 -0700 From: Poul-Henning Kamp Message-Id: <199504051530.IAA08540@ref.tfs.com> Subject: Re: swap always use at least 64KB ? To: bde@zeta.org.au (Bruce Evans) Date: Wed, 5 Apr 1995 08:30:25 -0700 (PDT) Cc: davidg@Root.COM, luigi@labinfo.iet.unipi.it, hackers@FreeBSD.org In-Reply-To: <199504051052.UAA16461@godzilla.zeta.org.au> from "Bruce Evans" at Apr 5, 95 08:52:05 pm Content-Type: text Content-Length: 818 Sender: hackers-owner@FreeBSD.org Precedence: bulk > > The first swap block is always pre-allocated. This was done to work around > >a problem with people putting their swap partition at the beginning of their > >disk (the system would happily try to destroy the label). I suppose it would > >be better to change swapinfo/pstat to not include the first block of swap > >space in its report. > > There must be bugs in the write protection of the label for that to happen. > > The diskslice "driver" snoops on writes to label sector(s) and rejects > writing of invalid labels even when write protection is off. Sure, but then you would crash with a "swap pager write error" instead... -- Poul-Henning Kamp -- TRW Financial Systems, Inc. 'All relevant people are pertinent' && 'All rude people are impertinent' => 'no rude people are relevant'