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Date: Thu, 6 Feb 1997 15:02:39 -0800
From: "Jin Guojun[ITG]" <jin@george.lbl.gov>
Message-Id: <199702062302.PAA04566@george.lbl.gov>
To: hackers@freebsd.org
Subject: how to find where system hanging?
Cc: bugs@freebsd.org
Sender: owner-bugs@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

I have a ATM driver that works well under 2.1.6-RELEASE or earlier.
However, under 2.2 serial release, it gets hanging frequently.
Before 2.2-BETA, it hangs about once a day or less. Under 2.2-GAMMA,
it gets hanging very often, sometimes it hangs just after booting up.

Is there any way to force coredump when the system is hanging?
Or is there a mechanism to trace where it is hanging.
Any hints what part of the kernel changing would cause this problem.

Please help!

Thanks in advance,

-Jin