From patchwork Wed Nov 18 14:51:52 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Slaby X-Patchwork-Id: 38749 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id DC4961007D1 for ; Thu, 19 Nov 2009 01:57:10 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757546AbZKROwD (ORCPT ); Wed, 18 Nov 2009 09:52:03 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755187AbZKROwC (ORCPT ); Wed, 18 Nov 2009 09:52:02 -0500 Received: from server1.wserver.cz ([82.113.45.157]:51261 "EHLO server1.wserver.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753962AbZKROv7 (ORCPT ); Wed, 18 Nov 2009 09:51:59 -0500 Received: from localhost.localdomain (unknown [82.113.46.245]) by server1.wserver.cz (Postfix) with ESMTP id 303D2C4D3A; Wed, 18 Nov 2009 16:00:56 +0100 (CET) From: Jiri Slaby To: jirislaby@gmail.com Cc: mingo@elte.hu, nhorman@tuxdriver.com, sfr@canb.auug.org.au, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, marcin.slusarz@gmail.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, torvalds@linux-foundation.org, Jiri Slaby , James Morris , Heiko Carstens , "David S. Miller" , sparclinux@vger.kernel.org Subject: [PATCH 06/16] SPARC: use ACCESS_ONCE for rlimits Date: Wed, 18 Nov 2009 15:51:52 +0100 Message-Id: <1258555922-2064-6-git-send-email-jslaby@novell.com> X-Mailer: git-send-email 1.6.4.2 In-Reply-To: <4B040A03.2020508@gmail.com> References: <4B040A03.2020508@gmail.com> Sender: sparclinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: sparclinux@vger.kernel.org Make sure compiler won't do weird things with limits. E.g. fetching them twice may return 2 different values after writable limits are implemented. Signed-off-by: Jiri Slaby Cc: James Morris Cc: Heiko Carstens Cc: Andrew Morton Cc: Ingo Molnar Cc: "David S. Miller" Cc: sparclinux@vger.kernel.org Acked-by: David S. Miller --- arch/sparc/kernel/sys_sparc_64.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c index e2d1024..004ed47 100644 --- a/arch/sparc/kernel/sys_sparc_64.c +++ b/arch/sparc/kernel/sys_sparc_64.c @@ -361,6 +361,7 @@ EXPORT_SYMBOL(get_fb_unmapped_area); void arch_pick_mmap_layout(struct mm_struct *mm) { unsigned long random_factor = 0UL; + unsigned long gap; if (current->flags & PF_RANDOMIZE) { random_factor = get_random_int(); @@ -375,9 +376,10 @@ void arch_pick_mmap_layout(struct mm_struct *mm) * Fall back to the standard layout if the personality * bit is set, or if the expected stack growth is unlimited: */ + gap = ACCESS_ONCE(current->signal->rlim[RLIMIT_STACK].rlim_cur); if (!test_thread_flag(TIF_32BIT) || (current->personality & ADDR_COMPAT_LAYOUT) || - current->signal->rlim[RLIMIT_STACK].rlim_cur == RLIM_INFINITY || + gap == RLIM_INFINITY || sysctl_legacy_va_layout) { mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; mm->get_unmapped_area = arch_get_unmapped_area; @@ -385,9 +387,7 @@ void arch_pick_mmap_layout(struct mm_struct *mm) } else { /* We know it's 32-bit */ unsigned long task_size = STACK_TOP32; - unsigned long gap; - gap = current->signal->rlim[RLIMIT_STACK].rlim_cur; if (gap < 128 * 1024 * 1024) gap = 128 * 1024 * 1024; if (gap > (task_size / 6 * 5))