From owner-freebsd-hackers Sat Apr 5 13:33:21 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id NAA28418 for hackers-outgoing; Sat, 5 Apr 1997 13:33:21 -0800 (PST) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.50]) by freefall.freebsd.org (8.8.5/8.8.5) with SMTP id NAA28412 for ; Sat, 5 Apr 1997 13:33:19 -0800 (PST) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id OAA23667; Sat, 5 Apr 1997 14:14:39 -0700 From: Terry Lambert Message-Id: <199704052114.OAA23667@phaeton.artisoft.com> Subject: Re: kern/3184: vnodes are used after they are freed. (dup alloc?) To: Tor.Egge@idi.ntnu.no (Tor Egge) Date: Sat, 5 Apr 1997 14:14:39 -0700 (MST) Cc: terry@lambert.org, dfr@nlsystems.com, dg@root.com, ponds!rivers@dg-rtp.dg.com, freebsd-hackers@freebsd.org In-Reply-To: <199704052056.WAA06400@pat.idt.unit.no> from "Tor Egge" at Apr 5, 97 10:56:08 pm X-Mailer: ELM [version 2.4 PL24] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > > > - Let getnewvnode call VOP_ISLOCKED and skip locked nodes on the > > > so-called free list. > > > > There's no holder, so it isn't locked. If it were locked via VOP_LOCK, > > then you wouldn'r be having this problem in the first place, since a > > VOP_LOCK will prevent a node from being vclean()'ed (that's the whole > > point of the NFS changes Doug has been trying to deal with, if you > > followed his postings on them). > > Wrong. Under some circumstances, the vnode is locked. See the end of vputrele. I should have said that there's no *guarantee* that there is a holder or that it is locked. The approach will fix some circumstances, but will fail for others without the *guarantee*. Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.