From owner-freebsd-hackers Sat Jan 30 21:15:11 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id VAA10907 for freebsd-hackers-outgoing; Sat, 30 Jan 1999 21:15:11 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from apollo.backplane.com (apollo.backplane.com [209.157.86.2]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id VAA10902 for ; Sat, 30 Jan 1999 21:15:09 -0800 (PST) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.2/8.9.1) id VAA94603; Sat, 30 Jan 1999 21:15:06 -0800 (PST) (envelope-from dillon) Date: Sat, 30 Jan 1999 21:15:06 -0800 (PST) From: Matthew Dillon Message-Id: <199901310515.VAA94603@apollo.backplane.com> To: Terry Lambert Cc: rch@iserve.net (Robert Hough), freebsd-hackers@FreeBSD.ORG Subject: Re: pwd.db corruption References: <199901310041.RAA27222@usr04.primenet.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :> I'm running a machine with FreeBSD 2.2.2-RELEASE and about 4 times now, the :> pwd.db file has become corrupt. When this happens, it wont authenticate :> anyone, and I have to reboot into single user mode, remove the pwd.db :> (rename it to pwd.old basically), and add a new user. After a reboot, it is :... : :This is a known bug, having to do with the reclaim of mmap'ed pages :and their reuse before they have been disaaciated from all of the :objects that reference them. : :The problem is exacerbated by cron, which modifies the return values :in the read-only pages pointed to by the static struct passwd that's :passed back (they point into the entries in the passwd database). :After the COW fault on the pages, they tend to get written back after :a reclaim. : :I most frequently see this as a corrupt crontab; it really depends :on what's running and what file is having pages thrashed in and out :of core. : :Upgrading to 4.0-current appears to fix this. : :There are a number of bugs in 3.0 that aren't in the 3.0-stable :branch; a shirt tail relative of this bug os one of them. : :The 4.0 fixes that haven't been back-ported to 3.0-STABLE are :probably enough, at this point, to justify using 4.0. : : : Terry Lambert : terry@lambert.org Hmm. If you recall the general area of the bug fix related to this problem I can research it. *All* VM bugs fixed in 4.x should have already been backported to 3.x, but a few sometimes get missed ( e.g. like that NFS corruption bug fix ). Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message