tcp-ip crashing BSD4.3

[Amos Shapir]

We are running 4.3BSD on a vax/785, connecting to a VM370-compatible (NAS) via
ethernet (DEUNA) using ftp & telnet. When the system is loaded heavily
(load > 10) and the connection is on, it often crashes with 'panic: Reserved
operand' at the 'ldpctx' instruction in 'Resume' - in short, the kernel stack
got screwd up; it seems that somewhere in the tcp-ip part of the kernel
(or the DEUNA driver) something is not spl-ed correctly.

The same package communicates correctly with a VMS system, and also functions
ok when the load is light. Has anybody ever heard of such a problem?
or a solution?
Thanks,
-- 
	Amos Shapir

National Semiconductor (Israel)
6 Maskit st. P.O.B. 3007, Herzlia 46104, Israel
(01-972) 52-522261
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