From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755908Ab2CFQT6 (ORCPT ); Tue, 6 Mar 2012 11:19:58 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:14866 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755650Ab2CFQTu (ORCPT ); Tue, 6 Mar 2012 11:19:50 -0500 X-Authority-Analysis: v=2.0 cv=Wf+OmjdX c=1 sm=0 a=ZycB6UtQUfgMyuk2+PxD7w==:17 a=XQbtiDEiEegA:10 a=UBy9sU4F98IA:10 a=CZDfYd8cBUwA:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=VwQbUJbxAAAA:8 a=meVymXHHAAAA:8 a=koGQc5_6AAAA:8 a=r1SSx9MgkuVJm8cjJMoA:9 a=yFlQdl3_maAO-4_PlrcA:7 a=9AGU4-qqYIQA:10 a=dR6KtR_F_aoA:10 a=Zh68SRI7RUMA:10 a=jeBq3FmKZ4MA:10 a=ZycB6UtQUfgMyuk2+PxD7w==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.80.29 Message-Id: <20120306161946.377520329@goodmis.org> User-Agent: quilt/0.50-1 Date: Tue, 06 Mar 2012 11:16:43 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-rt-users Cc: Thomas Gleixner , Carsten Emde , John Kacur , stable-rt@vger.kernel.org Subject: [PATCH RT 07/25][RFC 3.0.23-rt39-rc1] x86: vdso: Remove bogus locking in update_vsyscall_tz() References: <20120306161636.491172179@goodmis.org> Content-Disposition: inline; filename=0007-x86-vdso-Remove-bogus-locking-in-update_vsyscall_tz.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner Changing the sequence count in update_vsyscall_tz() is completely pointless. The vdso code copies the data unprotected. There is no point to change this as sys_tz is nowhere protected at all. See sys_gettimeofday(). Signed-off-by: Thomas Gleixner Cc: stable-rt@vger.kernel.org Signed-off-by: Steven Rostedt --- arch/x86/kernel/vsyscall_64.c | 5 ----- 1 files changed, 0 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/vsyscall_64.c b/arch/x86/kernel/vsyscall_64.c index 0a7dc13..c378a18 100644 --- a/arch/x86/kernel/vsyscall_64.c +++ b/arch/x86/kernel/vsyscall_64.c @@ -58,12 +58,7 @@ DEFINE_VVAR(struct vsyscall_gtod_data, vsyscall_gtod_data) = void update_vsyscall_tz(void) { - unsigned long flags; - - write_seqlock_irqsave(&vsyscall_gtod_data.lock, flags); - /* sys_tz has changed */ vsyscall_gtod_data.sys_tz = sys_tz; - write_sequnlock_irqrestore(&vsyscall_gtod_data.lock, flags); } void update_vsyscall(struct timespec *wall_time, struct timespec *wtm, -- 1.7.8.3