Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932304AbWBPQJ3 (ORCPT ); Thu, 16 Feb 2006 11:09:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932307AbWBPQJ3 (ORCPT ); Thu, 16 Feb 2006 11:09:29 -0500 Received: from mo01.iij4u.or.jp ([210.130.0.20]:21733 "EHLO mo01.iij4u.or.jp") by vger.kernel.org with ESMTP id S932304AbWBPQJ3 (ORCPT ); Thu, 16 Feb 2006 11:09:29 -0500 Date: Fri, 17 Feb 2006 01:09:19 +0900 (JST) Message-Id: <20060217.010919.121148551.toriatama@inter7.jp> To: paulkf@microgate.com Cc: linux-kernel@vger.kernel.org Subject: Re: PPP with PCMCIA modem stalls on 2.6.10 or later From: Kouji Toriatama In-Reply-To: <1140019368.3119.12.camel@amdx2.microgate.com> References: <1139937159.3189.4.camel@amdx2.microgate.com> <20060215.221135.121135595.toriatama@inter7.jp> <1140019368.3119.12.camel@amdx2.microgate.com> X-Mailer: Mew version 4.2 on Emacs 21.4 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1718 Lines: 46 Paul Fulghum wrote: > Try the following patch, and report the syslog output. > > This may be lost receive data due to full flip buffer. > 2.6.9 would try processing rx data in the ISR if the > flip buffer was full. This violated locking requirements > and was changed to only process rx data in scheduled work. > This can slow the processing of data. I have tried your patch. The following is a part of syslog output. ------------------------------------------------------------------ Feb 16 23:52:40 moka kernel: receive_chars:flip full:low_latency=0 Feb 16 23:52:40 moka kernel: receive_chars:flip full:discard char ------------------------------------------------------------------ I have got this pair of two lines many times while running the wget command. > Also try using the setserial utility to set > the 'low_latency' option for the device. That should > operate the same as 2.6.9 (which can be dangerous). With 'low_latency' option in 2.6.15 with your patch, the problem did not occur and no output from syslog. > The improved flip buffering code in 2.6.16-rc3 > should also prevent any loss of data. If possible, > try 2.6.16-rc3. I have tried 2.6.16-rc3. With or without 'low_latency' option, the problem did not occur. It seems to work fine! I will use 2.6.16-rc3 or later. If you have any additional plan to pin down this problem, I will try your patch. Thank you for your help, Kouji Toriatama - 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/