Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753975Ab2FSJLO (ORCPT ); Tue, 19 Jun 2012 05:11:14 -0400 Received: from lxorguk.ukuu.org.uk ([81.2.110.251]:35558 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751002Ab2FSJLN (ORCPT ); Tue, 19 Jun 2012 05:11:13 -0400 Date: Tue, 19 Jun 2012 10:14:47 +0100 From: Alan Cox To: Darren Hart Cc: Tomoya MORINAGA , Linux Kernel Mailing List , Feng Tang , Alexander Stein , Greg Kroah-Hartman , Alan Cox , linux-serial@vger.kernel.org Subject: Re: [RFC PATCH] pch_uart: Add eg20t_port lock field, avoid recursive spinlocks Message-ID: <20120619101447.74cbd9a1@pyramind.ukuu.org.uk> In-Reply-To: <4FDFA09A.4030405@linux.intel.com> References: <8854635ac5471f8671b93c65e3663eb1cb204c9d.1338454156.git.dvhart@linux.intel.com> <4FC90BAD.3080606@linux.intel.com> <4FCE8307.3050901@linux.intel.com> <4FDFA09A.4030405@linux.intel.com> X-Mailer: Claws Mail 3.8.0 (GTK+ 2.24.8; x86_64-redhat-linux-gnu) Face: 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 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1307 Lines: 33 On Mon, 18 Jun 2012 14:41:46 -0700 Darren Hart wrote: > > > On 06/05/2012 04:48 PM, Tomoya MORINAGA wrote: > > On Wed, Jun 6, 2012 at 7:07 AM, Darren Hart wrote: > >> Are there still concerns about the additional lock? I'll resend V2 > >> tomorrow with the single whitespace fix if I don't hear anything back today. > > > > I understand your saying. Looks good. > > However, I am not expert of linux-uart core system. > > So, I'd like UART maintainer to give us your opinion. > > Greg, Alan, > > any concerns with the locking approach I've adopted in the patch? Only the one I noted in my reply the first time around which is that you can't permit tty->low_latency=1 unless your tty receive path is not an IRQ path. From a locking point of view the change makes sense anyway. Going back over it your console locking also needs care - an oops or printk within the areas the private lock covers will hang the box. That should also probably be a trylock style lock as with the other lock on that path Alan -- 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/