Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757059Ab3EHRNA (ORCPT ); Wed, 8 May 2013 13:13:00 -0400 Received: from mail-pb0-f49.google.com ([209.85.160.49]:60277 "EHLO mail-pb0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753803Ab3EHRM7 (ORCPT ); Wed, 8 May 2013 13:12:59 -0400 Date: Thu, 9 May 2013 01:12:48 +0800 From: Wang YanQing To: Peter Hurley Cc: Greg KH , jslaby@suse.cz, linux-kernel@vger.kernel.org Subject: Re: [PATCH]TTY: Fix tty can't be restarted by TCXONC ioctl request Message-ID: <20130508171247.GA6925@udknight> Mail-Followup-To: Wang YanQing , Peter Hurley , Greg KH , jslaby@suse.cz, linux-kernel@vger.kernel.org References: <20130507184734.GA2459@udknight> <20130507185800.GA10713@kroah.com> <20130508015545.GA1937@udknight> <20130508020200.GA15695@kroah.com> <20130508131624.GA1938@udknight> <518A6CAF.9020301@hurleysoftware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <518A6CAF.9020301@hurleysoftware.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1153 Lines: 31 On Wed, May 08, 2013 at 11:18:07AM -0400, Peter Hurley wrote: > On 05/08/2013 09:16 AM, Wang YanQing wrote: > > On Tue, May 07, 2013 at 07:02:00PM -0700, Greg KH wrote: > >> What about Peter's comments on this patch? > >> > > Peter's comments will import policy, > > > > I means we should let userspace to decide whether > > and when to restart tty with the mechanism of TCXONC > > instead of restart tty accidental when make n_tty_set_termios > > call. > > There would be no accidental restart. Userspace is specifically > disabling user-controlled output flow control by clearing > IXON in termios. Userspace is _expecting_ a 'started' tty. > > If you insist that this must be controllable from userspace, > then that is already possible: > > tcflow(fd, TCOOFF); > tcflow(fd, TCOON); Indeed you can't do what you said with TCOOFF and TCOON if you read the codes, that's what this patch fix. Thanks. -- 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/