From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752551Ab0ASN4V (ORCPT ); Tue, 19 Jan 2010 08:56:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751710Ab0ASN4U (ORCPT ); Tue, 19 Jan 2010 08:56:20 -0500 Received: from smtp-out003.kontent.com ([81.88.40.217]:54677 "EHLO smtp-out003.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751522Ab0ASN4T (ORCPT ); Tue, 19 Jan 2010 08:56:19 -0500 From: Oliver Neukum To: Alan Cox Subject: Re: [REGRESSION] "USB: use kfifo to buffer usb-generic serial writes" causes gobi_loader to hang Date: Tue, 19 Jan 2010 14:57:00 +0100 User-Agent: KMail/1.12.2 (Linux/2.6.33-rc3-0.1-default; KDE/4.3.1; x86_64; ; ) Cc: Matthew Garrett , dvomlehn@cisco.com, gregkh@suse.de, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org References: <20100117025535.GB7045@srcf.ucam.org> <201001191420.29652.oliver@neukum.org> <20100119132934.0c1688f7@lxorguk.ukuu.org.uk> In-Reply-To: <20100119132934.0c1688f7@lxorguk.ukuu.org.uk> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201001191457.00504.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Dienstag, 19. Januar 2010 14:29:34 schrieb Alan Cox: > On Tue, 19 Jan 2010 14:20:29 +0100 > Oliver Neukum wrote: > > > Am Montag, 18. Januar 2010 21:14:16 schrieb Matthew Garrett: > > > > > drivers/usb/serial/generic.c: usb_serial_generic_write - port 0, 1565 > > > bytes > > > drivers/usb/serial/generic.c: usb_serial_generic_write - put 0 bytes > > > into fifo > > > drivers/usb/serial/generic.c: usb_serial_generic_read_bulk_callback - > > > port 0 > > > > If the FIFO is full we can do nothing. Please try the attached patch. > > If the FIFO is full how are we getting called - we should have throttled > earlier if there is any flow control (including 'look no URBs' cases) ? The log shows no call to usb_serial_generic_write_room() Do you consider this a bug in the tty layer? Regards Oliver