From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753162AbaIIXki (ORCPT ); Tue, 9 Sep 2014 19:40:38 -0400 Received: from shards.monkeyblade.net ([149.20.54.216]:33854 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753123AbaIIXkh (ORCPT ); Tue, 9 Sep 2014 19:40:37 -0400 Date: Tue, 09 Sep 2014 16:40:35 -0700 (PDT) Message-Id: <20140909.164035.1538611197997884601.davem@davemloft.net> To: andreas@gaisler.com Cc: sparclinux@vger.kernel.org, sam@ravnborg.org, linux-kernel@vger.kernel.org, software@gaisler.com Subject: Re: [PATCH] sparc: leon: Fix race condition between leon_cycles_offset and timer_interrupt From: David Miller In-Reply-To: <1409324958-22902-1-git-send-email-andreas@gaisler.com> References: <1409324958-22902-1-git-send-email-andreas@gaisler.com> X-Mailer: Mew version 6.5 on Emacs 24.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.7 (shards.monkeyblade.net [149.20.54.216]); Tue, 09 Sep 2014 16:40:36 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andreas Larsson Date: Fri, 29 Aug 2014 17:09:18 +0200 > This makes sure that leon_cycles_offset takes the pending bit into > account and that leon_clear_clock_irq clears the pending bit. Otherwise, > if leon_cycles_offset is executed after the timer has wrapped but before > timer_interrupt has increased timer_cs_internal_counter, time can be > perceived to go backwards. > > Signed-off-by: Andreas Larsson Applied.