From owner-freebsd-current Sat May 5 17:17:20 2001 Delivered-To: freebsd-current@freebsd.org Received: from prism.flugsvamp.com (cb58709-a.mdsn1.wi.home.com [24.17.241.9]) by hub.freebsd.org (Postfix) with ESMTP id 2ED6637B423 for ; Sat, 5 May 2001 17:17:17 -0700 (PDT) (envelope-from jlemon@flugsvamp.com) Received: (from jlemon@localhost) by prism.flugsvamp.com (8.11.0/8.11.0) id f460GdJ05790; Sat, 5 May 2001 19:16:39 -0500 (CDT) (envelope-from jlemon) Date: Sat, 5 May 2001 19:16:39 -0500 From: Jonathan Lemon To: Archie Cobbs Cc: Jonathan Lemon , tlambert@primenet.com, current@FreeBSD.ORG Subject: Re: panic in fxp driver Message-ID: <20010505191639.N670@prism.flugsvamp.com> References: <200105031828.f43ISSi06097@prism.flugsvamp.com> <200105052304.f45N4RO00676@arch20m.dellroad.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0pre2i In-Reply-To: <200105052304.f45N4RO00676@arch20m.dellroad.org> Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Sat, May 05, 2001 at 04:04:27PM -0700, Archie Cobbs wrote: > Jonathan Lemon writes: > > >Please consider the case where there are two mbuf chains being > > >transmitted, which look like this: > > > > Um. "Not Possible". > > I thought m_copypacket() of a cluster mbuf would yield exactly > this situation (two headers pointing to the same data region). Well, only external mbufs can be shared, not mbuf chains; and clusters are accessed through the (unused) mbuf that comprises the chain. I believe Terry may have been referring to some local modifications that is in his code, which permits the scenario he describes. -- Jonathan To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message