From patchwork Fri Aug 16 11:43:12 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Viresh Kumar X-Patchwork-Id: 19225 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-qe0-f69.google.com (mail-qe0-f69.google.com [209.85.128.69]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id 9E7E3246AB for ; Fri, 16 Aug 2013 11:44:50 +0000 (UTC) Received: by mail-qe0-f69.google.com with SMTP id 1sf2163051qec.4 for ; Fri, 16 Aug 2013 04:44:50 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:x-gm-message-state:delivered-to:from:to:cc:subject :date:message-id:in-reply-to:references:in-reply-to:references :x-original-sender:x-original-authentication-results:precedence :mailing-list:list-id:list-post:list-help:list-archive :list-unsubscribe; bh=8QTrQ3JmWFhadzGDhh3pA6BN9Lgm30xM4Ky3POfogc0=; b=nQTEJce0Fi+FKuRYUBRacZMAx3T7iMXAZmzJQUfk4s8+67UeT/YrSn6TYUwZ8LasgH ULSmHkAwOOTEPlwItk9zs1BgTUSh+jmA0oejEYYtUOVDLSxS54A+1IYzH215d/lplmsg ixQRxkJK+C009vObV6/TpE+E5fpsoCA8LpS8++Z0pOga7X+P2cGCyx6bjwMrCvKVH0DK 0WIQqQI+44DZfAcjsDOVu5jiwL7yc9EHZKFAc1uI7ZqYRqV4F4uFvoZZHHuz+r788c4n VSv4kYc5LuHODptl0gdo2q6uLGaTuCyc8eGLWxtjNG8KVuMXSEsh/Dz1tXteYAbPU5MR 0FQg== X-Received: by 10.236.19.225 with SMTP id n61mr395902yhn.8.1376653490364; Fri, 16 Aug 2013 04:44:50 -0700 (PDT) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.49.60.70 with SMTP id f6ls719094qer.59.gmail; Fri, 16 Aug 2013 04:44:50 -0700 (PDT) X-Received: by 10.221.47.193 with SMTP id ut1mr871430vcb.8.1376653490275; Fri, 16 Aug 2013 04:44:50 -0700 (PDT) Received: from mail-ve0-f169.google.com (mail-ve0-f169.google.com [209.85.128.169]) by mx.google.com with ESMTPS id aj7si218601vec.97.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 16 Aug 2013 04:44:50 -0700 (PDT) Received-SPF: neutral (google.com: 209.85.128.169 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) client-ip=209.85.128.169; Received: by mail-ve0-f169.google.com with SMTP id db10so1375587veb.0 for ; Fri, 16 Aug 2013 04:44:50 -0700 (PDT) X-Gm-Message-State: ALoCoQlSIUjHjLJLlBJ3QITWEr4gW/PK8koIywboK74vqTuvV7rGxAxyyb3uxXWesENclQUQgPgq X-Received: by 10.58.45.70 with SMTP id k6mr885586vem.9.1376653490202; Fri, 16 Aug 2013 04:44:50 -0700 (PDT) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patches@linaro.org Received: by 10.220.174.196 with SMTP id u4csp64139vcz; Fri, 16 Aug 2013 04:44:49 -0700 (PDT) X-Received: by 10.68.235.37 with SMTP id uj5mr1181894pbc.85.1376653489390; Fri, 16 Aug 2013 04:44:49 -0700 (PDT) Received: from mail-pd0-f178.google.com (mail-pd0-f178.google.com [209.85.192.178]) by mx.google.com with ESMTPS id iy4si871008pbb.125.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 16 Aug 2013 04:44:49 -0700 (PDT) Received-SPF: neutral (google.com: 209.85.192.178 is neither permitted nor denied by best guess record for domain of viresh.kumar@linaro.org) client-ip=209.85.192.178; Received: by mail-pd0-f178.google.com with SMTP id w10so2132766pde.23 for ; Fri, 16 Aug 2013 04:44:49 -0700 (PDT) X-Received: by 10.66.149.231 with SMTP id ud7mr2763461pab.8.1376653488978; Fri, 16 Aug 2013 04:44:48 -0700 (PDT) Received: from localhost ([122.172.193.46]) by mx.google.com with ESMTPSA id 7sm2898099paf.22.1969.12.31.16.00.00 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Fri, 16 Aug 2013 04:44:47 -0700 (PDT) From: Viresh Kumar To: gregkh@linuxfoundation.org, jslaby@suse.cz Cc: linaro-kernel@lists.linaro.org, patches@linaro.org, linux-serial@vger.kernel.org, Viresh Kumar Subject: [PATCH 11/25] tty: serial: lpc32xx_hs: drop uart_port->lock before calling tty_flip_buffer_push() Date: Fri, 16 Aug 2013 17:13:12 +0530 Message-Id: <91cd5fec75d8cbd56a60e105c4252d8589e8fe26.1376651114.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 1.7.12.rc2.18.g61b472e In-Reply-To: References: In-Reply-To: References: X-Removed-Original-Auth: Dkim didn't pass. X-Original-Sender: viresh.kumar@linaro.org X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 209.85.128.169 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org Precedence: list Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org List-ID: X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , The -rt patch triggers a lockdep warning for serial drivers if tty_flip_buffer_push() is called with uart_port->lock locked. This never shows up on UP kernels. Release the port lock before calling tty_flip_buffer_push() and reacquire it after the call. Similar stuff was already done for few other drivers in the past, like: commit 2389b272168ceec056ca1d8a870a97fa9c26e11a Author: Thomas Gleixner Date: Tue May 29 21:53:50 2007 +0100 [ARM] 4417/1: Serial: Fix AMBA drivers locking Signed-off-by: Viresh Kumar --- drivers/tty/serial/lpc32xx_hs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c index 8fdf6a8..701644f 100644 --- a/drivers/tty/serial/lpc32xx_hs.c +++ b/drivers/tty/serial/lpc32xx_hs.c @@ -279,7 +279,10 @@ static void __serial_lpc32xx_rx(struct uart_port *port) tmp = readl(LPC32XX_HSUART_FIFO(port->membase)); } + + spin_unlock(&port->lock); tty_flip_buffer_push(tport); + spin_lock(&port->lock); } static void __serial_lpc32xx_tx(struct uart_port *port)