From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932291AbWGGTuO (ORCPT ); Fri, 7 Jul 2006 15:50:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932289AbWGGTuO (ORCPT ); Fri, 7 Jul 2006 15:50:14 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:46825 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S932291AbWGGTuM (ORCPT ); Fri, 7 Jul 2006 15:50:12 -0400 Subject: Re: [PATCH] Airprime driver improvements to allow full speed EvDO transfers From: Alan Cox To: Sergei Organov Cc: Andrew Morton , gregkh@suse.de, linux-kernel@vger.kernel.org, linux-usb-devel@lists.sourceforge.net In-Reply-To: <87veq9cosq.fsf@javad.com> References: <1151646482.3285.410.camel@tahini.andynet.net> <20060630001021.2b49d4bd.akpm@osdl.org> <87veq9cosq.fsf@javad.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Fri, 07 Jul 2006 21:07:11 +0100 Message-Id: <1152302831.20883.63.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.6.2 (2.6.2-1.fc5.5) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ar Gwe, 2006-07-07 am 21:23 +0400, ysgrifennodd Sergei Organov: > It seems that there is much worse problem here. The amount of data that > has been inserted by the tty_insert_flip_string() could be up to > URB_TRANSFER_BUFFER_SIZE (=4096 bytes) and may easily exceed > TTY_THRESHOLD_THROTTLE (=128 bytes) defined in the > char/n_tty.c. You may throttle late but that is always true as there is an implicit race between the hardware signals and the chip FIFO on all UART devices. The buffering should be taking care of it, and the tty layer taking care not to over stuff the ldisc which I thought Paul had fixed while doing the locking wizardry Alan