From patchwork Fri Aug 16 11:43:26 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Viresh Kumar X-Patchwork-Id: 19239 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-vb0-f69.google.com (mail-vb0-f69.google.com [209.85.212.69]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id EBCD5246AB for ; Fri, 16 Aug 2013 11:46:24 +0000 (UTC) Received: by mail-vb0-f69.google.com with SMTP id e13sf2127510vbg.4 for ; Fri, 16 Aug 2013 04:46:24 -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=5OVSUj0ibwP181/QEWzFViNgiKdbx0+k1IL354EJkO4=; b=GjoWTQX/qZK8mFo2N7vcULbwTRJkutDIxhdW1FiyWo7X5eaHV/jXMHJdlZhOjpz8VR ItK5qbjZQdtt5cqbG/PQMk5YodWyE9JRdF4R1mN322X2Y2Y1gUD7f1uy/et7ckrIPWb1 OXE6SKgMBrvCC1fh81d6N7LQlyjqEE8UYmCbkllSI4IXv0ANDbrWMu+sZookFF8u98QY 0BHft3fqZdRHltPaL6UDs0sFAOomsV1GPzui+HHWoZLoZjz874AMVrVzThwmzM+UXTnp MrVGy/PIgSBx2F9/xaBz8MAEXm7FpAeqfc9Z0pc5CfbGlbIHL4/2zgWAcmH3BKmEJFdJ 5xjg== X-Received: by 10.236.163.67 with SMTP id z43mr380535yhk.27.1376653584673; Fri, 16 Aug 2013 04:46:24 -0700 (PDT) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.49.14.106 with SMTP id o10ls724086qec.36.gmail; Fri, 16 Aug 2013 04:46:24 -0700 (PDT) X-Received: by 10.59.8.232 with SMTP id dn8mr873652ved.8.1376653584550; Fri, 16 Aug 2013 04:46:24 -0700 (PDT) Received: from mail-vb0-f53.google.com (mail-vb0-f53.google.com [209.85.212.53]) by mx.google.com with ESMTPS id h4si227876vdw.32.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 16 Aug 2013 04:46:24 -0700 (PDT) Received-SPF: neutral (google.com: 209.85.212.53 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) client-ip=209.85.212.53; Received: by mail-vb0-f53.google.com with SMTP id i3so1493827vbh.26 for ; Fri, 16 Aug 2013 04:46:24 -0700 (PDT) X-Gm-Message-State: ALoCoQm5tJftRd82VCMDMAVuhKctSTfN/oWOXl1tRFhs7f1qexwm5RKHFcxeihQYcNu2otsTvkAP X-Received: by 10.52.249.102 with SMTP id yt6mr739015vdc.21.1376653584462; Fri, 16 Aug 2013 04:46:24 -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 u4csp64203vcz; Fri, 16 Aug 2013 04:46:23 -0700 (PDT) X-Received: by 10.66.186.12 with SMTP id fg12mr1094631pac.178.1376653583607; Fri, 16 Aug 2013 04:46:23 -0700 (PDT) Received: from mail-pb0-f54.google.com (mail-pb0-f54.google.com [209.85.160.54]) by mx.google.com with ESMTPS id g9si1468806pac.329.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 16 Aug 2013 04:46:23 -0700 (PDT) Received-SPF: neutral (google.com: 209.85.160.54 is neither permitted nor denied by best guess record for domain of viresh.kumar@linaro.org) client-ip=209.85.160.54; Received: by mail-pb0-f54.google.com with SMTP id ro12so1907747pbb.13 for ; Fri, 16 Aug 2013 04:46:23 -0700 (PDT) X-Received: by 10.66.170.138 with SMTP id am10mr2633983pac.51.1376653583205; Fri, 16 Aug 2013 04:46:23 -0700 (PDT) Received: from localhost ([122.172.193.46]) by mx.google.com with ESMTPSA id s6sm2928360pan.12.1969.12.31.16.00.00 (version=TLSv1.2 cipher=RC4-SHA bits=128/128); Fri, 16 Aug 2013 04:46:22 -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 , Tony Prisk Subject: [PATCH 25/25] tty: serial: vt8500: drop uart_port->lock before calling tty_flip_buffer_push() Date: Fri, 16 Aug 2013 17:13:26 +0530 Message-Id: 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: 209.85.212.53 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 Cc: Tony Prisk Signed-off-by: Viresh Kumar --- drivers/tty/serial/vt8500_serial.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c index 48af43d..b839b98 100644 --- a/drivers/tty/serial/vt8500_serial.c +++ b/drivers/tty/serial/vt8500_serial.c @@ -170,7 +170,9 @@ static void handle_rx(struct uart_port *port) tty_insert_flip_char(tport, c, flag); } + spin_unlock(&port->lock); tty_flip_buffer_push(tport); + spin_lock(&port->lock); } static void handle_tx(struct uart_port *port)