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Date: Sun, 15 Apr 2007 16:39:50 +0200
From: Stefan Weil <weil@mail.berlios.de>
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Subject: Re: [Qemu-devel] serial8250: too much work for irq4
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To: qemu-devel@nongnu.org

QEMU only emulates a serial interface without FIFO,
so Linux gets one interrupt per character sent or received.
And the emulation does not emulate the original speed
of the serial interface, but runs at fastest speed possible.

I get this log message every time when a program writes
more than a few lines, for example with QEMU emulating
Linux/MIPS when I start aptitude or call dmesg.

Without a working FIFO emulation, there is not much you
can do if you really need a serial console or other kind of
serial communication.

Stefan

Nigel Horne schrieb:
> In the mips emulator I often see "serial8250: too much work for irq4",
> particularity when running vi etc. Is that to be expected, and known
> about?
> If so, please ignore this ;-), if not, I thought you may like to know.
>
> -Nigel