From owner-freebsd-bugs Sat Jun 15 11:55:07 1996 Return-Path: owner-bugs Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id LAA08800 for bugs-outgoing; Sat, 15 Jun 1996 11:55:07 -0700 (PDT) Received: from matlock.mindspring.com (matlock.mindspring.com [204.180.128.10]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id LAA08788 for ; Sat, 15 Jun 1996 11:55:05 -0700 (PDT) Received: from halloran-eldar.lcs.mit.edu (halloran-eldar.lcs.mit.edu [18.26.0.159]) by matlock.mindspring.com (8.6.12/8.6.9) with SMTP id OAA01616 for ; Sat, 15 Jun 1996 14:54:41 -0400 Received: by halloran-eldar.lcs.mit.edu; (5.65/1.1.8.2/19Aug95-0530PM) id AA22749; Sat, 15 Jun 1996 14:54:36 -0400 Date: Sat, 15 Jun 1996 14:54:36 -0400 From: Garrett Wollman Message-Id: <9606151854.AA22749@halloran-eldar.lcs.mit.edu> To: Robert Sanders Cc: lists-freebsd-bugs@matlock.mindspring.com Subject: Re: kern/1293: Fatal trap 12: page fault while in kernel mode (PPP/modems/cyclades?) Newsgroups: lists.freebsd.bugs In-Reply-To: References: <199606051432.RAA20913@katiska.clinet.fi> Sender: owner-bugs@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk < said: > This has never happened in months of user PPP. I'd just stick to > userland PPP, but it randomly loses packets and gives erratic > performance. How does one begin to debug a "fatal double fault"? It is almost invariably caused by a kernel stack overflow, which is in turn caused by too much stack allocation or recursion (often infinite recursion due to bugs) in the kernel. -GAWollman -- Garrett A. Wollman | Shashish is simple, it's discreet, it's brief. ... wollman@lcs.mit.edu | Shashish is the bonding of hearts in spite of distance. Opinions not those of| It is a bond more powerful than absence. We like people MIT, LCS, ANA, or NSA| who like Shashish. - Claude McKenzie + Florent Vollant