From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755714Ab0JNTCZ (ORCPT ); Thu, 14 Oct 2010 15:02:25 -0400 Received: from kroah.org ([198.145.64.141]:51151 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755032Ab0JNTCX (ORCPT ); Thu, 14 Oct 2010 15:02:23 -0400 Date: Thu, 14 Oct 2010 11:45:11 -0700 From: Greg KH To: Stanislav Brabec Cc: MyungJoo Ham , Greg KH , linux-kernel@vger.kernel.org, kyungmin.park@samsung.com, Alan Cox , Arnd Bergmann , Andr Goddard Rosa , Jason Wang , linux-serial@vger.kernel.org Subject: Re: [PATCH] Serial: BUGFIX: uart_resume_port has an omitted condition. Message-ID: <20101014184511.GA17096@kroah.com> References: <1286949486-2446-1-git-send-email-myungjoo.ham@samsung.com> <20101013062605.GB4393@suse.de> <1286969205.6082.700.camel@hammer.site> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1286969205.6082.700.camel@hammer.site> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 13, 2010 at 01:26:45PM +0200, Stanislav Brabec wrote: > On Wed, 13 Oct 2010 15:38:13 +0900, MyungJoo Ham wrote: > > On Wed, Oct 13, 2010 at 3:26 PM, Greg KH wrote: > > > On Wed, Oct 13, 2010 at 02:58:06PM +0900, MyungJoo Ham wrote: > > > > Is this a regression? If so, from what working kernel? Or has this > > > always been this way? > > > > I don't think this is a regression to the previous version. Logically, > > it's matching the console_stop()-console_start() pair. > > This disparity appeared deliberately in 4547be78. If you need > no_console_suspend and the hardware lets the device in an undefined > state after resume (i. e. PXA270), you need to call subset of the > resume, even if the suspend counterpart was not called. Yes, I can > imagine that it may be a source of problems. > > Did you try the latest patches from Jason Wang from linux-serial list? > > > Such hang in serial and its mitigation is observed in 2.6.36 at > > arch/arm/mach-s5pv310 machines. In these machines, it hanged with > > console_suspend_enabled == 0 every time. > > It seems that support for no_console_suspend for all devices is becoming > more complicated. I guess that a new driver calls (maybe "save_state" > and "resume_state") or support for no_console_suspend directly in > drivers may be useful. Ok, so I'm guessing that this patch is not to be applied then, correct? thanks, greg k-h