Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!wuarchive!decwrl!mogul
From: mogul@decwrl.dec.com (Jeffrey Mogul)
Newsgroups: comp.unix.ultrix
Subject: Re: qe: Non existant memory interrupt
Message-ID: <354@jove.dec.com>
Date: 28 Mar 90 22:02:52 GMT
References: <1642@jimi.cs.unlv.edu> <10333@cbmvax.commodore.com>
Organization: DEC Western Research
Lines: 22

In article <10333@cbmvax.commodore.com> grr@cbmvax (George Robbins) writes:
>Well, the first comment is certainly bogus, since (illegally) long packets
>on your ethernet will cause a panic due to "chained packets".  I wouldn't
>be too surpries if there is some network disease that could cause the second.

I don't know anything about the non-existent memory problems; I've
never seen them but we may not have the relevant hardware/software
combination.

I do know that back a few versions ago (definitely Ultrix 1.2, maybe
in Ultrix 2.x) if a chained packet was received, the if_qe driver
would always panic.  (I know this because Dave Boggs was running
his Ethernet performance tests on our net and he sometimes sent
humongous packets.)

I also know that this appears to have been fixed in more recent
versions of the code; there is still a panic on chained packets,
but that is only for a "Should NEVER happen" condition on some status
flag, and in fact chained packets (i.e., packets > 2kbytes long) should
simply be discarded now.

-Jeff