Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751416AbaGJXKH (ORCPT ); Thu, 10 Jul 2014 19:10:07 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60378 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751287AbaGJXKF (ORCPT ); Thu, 10 Jul 2014 19:10:05 -0400 Date: Thu, 10 Jul 2014 16:14:32 -0700 From: Greg Kroah-Hartman To: Peter Hurley Cc: linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Seth Bollinger , Aaro Koskinen , Sam Ravnborg , "David S. Miller" , Thomas Bogendoerfer Subject: Re: [PATCH 0/2] fixes for empty tx buffer breakage Message-ID: <20140710231432.GA9423@kroah.com> References: <20140609205917.GA913@drone.musicnaut.iki.fi> <1404660593-12172-1-git-send-email-peter@hurleysoftware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1404660593-12172-1-git-send-email-peter@hurleysoftware.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 06, 2014 at 11:29:51AM -0400, Peter Hurley wrote: > Cc: Seth Bollinger > Cc: Aaro Koskinen > Cc: Sam Ravnborg > Cc: "David S. Miller" > Cc: Thomas Bogendoerfer > > Greg, > > I completed the audit of serial drivers after reports that > several Sun serial drivers were broken by > commit 717f3bbab3c7628736ef738fdbf3d9a28578c26c, > 'serial_core: Fix conditional start_tx on ring buffer not empty'. > > I apologize for not submitting this sooner. The delay was due to > an ongoing analysis of serial flow control prompted by Sam Ravnborg's > question: > > On 06/10/2014 03:24 PM, Sam Ravnborg wrote: > > I also noticed the typical pattern is: > > > > if (uart_circ_empty(xmit) || uart_tx_stopped(port)) > > > > Should you use this pattern also in sunsab.c? > > Unfortunately, that analysis revealed that tx flow control is > largely SMP-unsafe, and it's fairly easy to corrupt the hardware > state wrt. the tty flow control state. > > I'm still working on the solutions to that; they're too > extensive to submit for 3.16 anyway. So these should go into 3.16-final? Or 3.17? confused, greg k-h -- 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/