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Date: Thu, 8 May 1997 13:54:50 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199705080354.NAA02619@godzilla.zeta.org.au>
To: bruce@zuhause.mn.org, freebsd-current@FreeBSD.ORG
Subject: Re: Excessive tty-level buffer overflows
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>In a five minute period while running uucp via an external sportster
>33K modem at 57.6 KB on /dev/cuaa1, I received over 123,000 tty-level
>buffer overflows.  This is a dual CPU Pentium Pro Tyan ATX 1668,
>running in single CPU mode.  What does this mean?  Is it a shoddy
>16550 emulation?  My kernel is from Saturday, or thereabouts.

It's what happen when input arrives on an open port and nothing reads it.
Perhaps recent config changes broke the initialization of flow control
that normally prevents input from arriving.

Bruce