From owner-freebsd-stable Fri Jan 26 8:18:22 2001 Delivered-To: freebsd-stable@freebsd.org Received: from wyattearp.stanford.edu (wyattearp.Stanford.EDU [171.64.180.171]) by hub.freebsd.org (Postfix) with ESMTP id EDBDB37B401 for ; Fri, 26 Jan 2001 08:18:00 -0800 (PST) Received: (from richw@localhost) by wyattearp.stanford.edu (8.9.3/8.9.3) id IAA36629; Fri, 26 Jan 2001 08:17:59 -0800 (PST) (envelope-from richw) Date: Fri, 26 Jan 2001 08:17:58 -0800 (PST) From: Rich Wales X-Sender: richw@wyattearp.stanford.edu To: freebsd-stable@freebsd.org Subject: Can't get a crash dump?!? Message-ID: <20010126153344.35549.richw@wyattearp.stanford.edu> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG I'm running 4.2-STABLE (cvsup'ed on January 20) on a Pentium which I'm using as a firewall/bridge at home. For the most part, the system works well, but it crashes under a sus- tained heavy network load with "panic: m_dup: bogus m_pkthdr.len". I can produce this panic at will by trying to download a very large file. However, I've been completely unable to get a crash dump. I have "dumpdev" set in /etc/rc.conf, and the "swapon" command works during startup. (The box has 24MB of RAM, and the swap partition is over twice that big, so dumping should theoretically work.) If I include "options DDB" in the kernel configuration, then the system (eventually) panics and drops into DDB. I can do a trace and other DDB commands, but nothing I've tried so far will cause a crash dump to be written out. In particular, I've tried combinations of panic continue call boot(0) call boot(256) [ RB_DUMP flag value in ] but the best I can manage to do is get a "page fault while in kernel mode" panic and another DDB prompt. If I don't include "options DDB", then when the system eventually crashes, it goes haywire. Screenful after screenful of (presumably) panic messages whiz by on the monitor, and then a bunch of random color bars are displayed (as if video memory has been overwritten with random junk?), and then it reboots. I tried adding some "printf"s to dumpsys() (in kern/kern_shutdown.c), in order to see why it wasn't dumping, but none of my extra messages get printed -- suggesting that dumpsys() isn't even being called. Any ideas? Rich Wales richw@webcom.com http://www.webcom.com/richw/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message