Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758402AbZAWRmQ (ORCPT ); Fri, 23 Jan 2009 12:42:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755179AbZAWRmD (ORCPT ); Fri, 23 Jan 2009 12:42:03 -0500 Received: from marvin.heresymail.org ([87.106.62.5]:44367 "EHLO marvin.heresymail.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754365AbZAWRmB (ORCPT ); Fri, 23 Jan 2009 12:42:01 -0500 Message-ID: <497A0164.90409@walrond.org> Date: Fri, 23 Jan 2009 17:41:56 +0000 From: Andrew Walrond User-Agent: Thunderbird 2.0.0.19 (X11/20090105) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: serial8250 madness Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1607 Lines: 44 Is anyone active in the serial code? I thought I would make some in-house servers send output via ttyS0 from grub, kernel boot and console, like our rented remote servers do. I set it all up and basically nothing worked properly, so I started investigating with a null modem cable, setserial and cu to see what was happening. Machine A ttyS0 works fine. Can get grub output, kernel boot and console via ttyS0 as I wanted. ttyS1 doesn't work at all. It's detected, enabled in the bios etc etc but just doesn't work at all. Machine B ttyS0 and ttyS1 will both receive, but neither will send. Go figure. Tested using a null modem cable, setserial and cu against the known good machine above. Machine C Grub and kernel outputs fine during boot, right up til the serial8250 output appears in the kernel log, at which point it then prints 'LSR safety check engaged' and reboots. Tried again without the console=ttyS0,57600 kernel parameter and it boots OK but starts printing the 'LSR...' message again as soon as agetty tries to attach to ttyS0. Doesn't reboot though... The Machines are all amd64, various motherboards, identical distros using 2.6.28.1 kernel. Either I have a particularly motley collection of kit, or the serial code is in a pretty bad way. I can provide further info/testing if anyone is active/interested. Andrew Walrond -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/