Re: Linux-2.0.25 and 2.1.8

Andrew C. Esh (
Wed, 13 Nov 1996 09:42:22 -0600

>>>>> "Alain" == Alain Knaff <> writes:

>> Linus Torvalds <> wrote:
>>> The 2.1.8 release is more "interesting", and the big thing
>>> here is the new IPv6 code together with quite a number of
>>> cleanups for IPv4 (TCP retransmissions are really done by TCP,
>>> not by the IP layer like they used to be done). Thanks to
>>> Pedro for all the work on this.
>> It blew up ppp for me. It seems the strings returned from the
>> chat script were garbled, resulting in ppp not knowing it was
>> connected. Going back to 2.1.6 cured the problem without
>> making any changes to the ppp binary or config files. Here is
>> an exerpt of an NORMAL, successful ppp connect under 2.1.6:

Alain> Starting from 2.1.8, I noticed a similar problem. It went
Alain> away after doing setserial /dev/modem uart 16550 . For
Alain> some reason, the default, 16450, seems to no longer work
Alain> with more powerful uart's.

This fix has caused my mouse to start working, when it hadn't
before. I also tested my PPP connection with this fix in place, and it
works fine.

I noticed during bootup that the setserial "wild interrupt detection"
reports that the uarts are 16450. I changed my RedHat rc.serial to do
manual detection of the uarts instead of automatic. The second report
from setserial now reports the uarts as 16550, and everything works.

Nov 13 09:06:49 andrewes kernel: tty00 at 0x03f8 (irq = 4) is a 16450
Nov 13 09:06:49 andrewes kernel: tty01 at 0x02f8 (irq = 3) is a 16450

[root@andrewes log]# uname -a
Linux 2.1.9 #14 Tue Nov 12 17:12:21 CST 1996 i486
[root@andrewes log]# uptime
9:38am up 32 min, 3 users, load average: 0.34, 0.21, 0.19
[root@andrewes log]# setserial /dev/cua0 # (cua1 is a mouse, busy)
/dev/cua0, UART: 16550, Port: 0x03f8, IRQ: 4, Flags: spd_vhi

Andrew C. Esh
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