Date: Mon, 17 Feb 2003 20:39:27 +0100 From: Dag-Erling Smorgrav <des@ofug.org> To: Mike Tancsa <mike@sentex.net> Cc: freebsd-hackers@freebsd.org Subject: Re: debugging a repeating panic that does not produce a dump Message-ID: <xzpisvi4ryo.fsf@flood.ping.uio.no> In-Reply-To: <5.2.0.9.0.20030217135903.064d7378@marble.sentex.ca> (Mike Tancsa's message of "Mon, 17 Feb 2003 14:29:26 -0500") References: <5.2.0.9.0.20030217091242.05b184b0@marble.sentex.ca> <5.2.0.9.0.20030217091242.05b184b0@marble.sentex.ca> <5.2.0.9.0.20030217135903.064d7378@marble.sentex.ca>
next in thread | previous in thread | raw e-mail | index | archive | help
Mike Tancsa <mike@sentex.net> writes:
> ns4# nm /kernel | grep \^c0174 | sort
> [...]
> c01747d4 T makedev
> c01748f4 T freedev
This is it (makedev)
> Does this actually show the location ?
> ns4# gdb -k kernel.debug
> [...]
> (kgdb) list *0xc0174830
> 0xc0174830 is in makedev (/usr/src/sys/kern/kern_conf.c:208).
> 203 if (x == umajor(NOUDEV) && y == uminor(NOUDEV))
> 204 Debugger("makedev of NOUDEV");
> 205 udev = (x << 8) | y;
> 206 hash = udev % DEVT_HASH;
> 207 LIST_FOREACH(si, &dev_hash[hash], si_hash) {
> 208 if (si->si_udev == udev)
> 209 return (si);
> 210 }
> 211 if (stashed >= DEVT_STASH) {
> 212 MALLOC(si, struct specinfo *, sizeof(*si), M_DEVT,
> (kgdb)
Yep. Looks like si is garbage:
> fault virtual address = 0x211e6d36
is most likely the value of si at the time of the crash. It's nowhere
near kernel memory (which starts at 0xc0000000).
If / when you get a dump, show me the backtrace and the value of x, y
and udev (as reported by gdb operating on the recovered core)
> > How do you build your kernels - 'make buildkernel' or manually?
> Always make buildkernel. I have a debug kernel built as well
> (makeoptions DEBUG=-g)
That's what I wanted to know.
DES
--
Dag-Erling Smorgrav - des@ofug.org
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?xzpisvi4ryo.fsf>