Serial console problems with stable/8

Oliver Fromme olli at
Mon Sep 13 17:00:15 UTC 2010

John Baldwin wrote:
 > On Monday, September 13, 2010 11:55:27 am Oliver Fromme wrote:
 > > I think the boot.config stuff might be a red herring.
 > > The console breaks (i.e. freezes) as soon as I try to run
 > > a getty process on it -- That seems to indicate that getty
 > > does *something* to the console device which causes the
 > > problem.  The wchan "ttydcd" seems to indicate is has
 > > something to do with carrier detection or flow control.
 > > This points to the uart driver as the culprit which
 > > replaced sio.
 > Well, /dev/ttyXX have always waited for carrier detect, whereas
 > /dev/cuaXX (the call-out devices) have not.

Well, before the update I had ttyd0 in /etc/ttys (this is
the default in FreeBSD 7.x), so it should have waited for
carrier detect, too.

 > That was so that you could hook a modem up to a serial port and getty
 > would not return from open(2) and print a login banner until someone
 > dialed the modem and connected.  I think Jeremy has already given you
 > some good things to try (such as 3wire.9600) to debug this instead.

Yes, I will try that ...  But with the 3wire entry I won't
have any flow control at all, so output can be lost, right?
Doesn't sound like a good solution.

Best regards

Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M.
Handelsregister: Registergericht Muenchen, HRA 74606,  Geschäftsfuehrung:
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chen, HRB 125758,  Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart

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