From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756792AbaKTWFM (ORCPT ); Thu, 20 Nov 2014 17:05:12 -0500 Received: from terminus.zytor.com ([198.137.202.10]:51422 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756141AbaKTWFK (ORCPT ); Thu, 20 Nov 2014 17:05:10 -0500 Date: Thu, 20 Nov 2014 14:04:26 -0800 From: tip-bot for Andy Lutomirski Message-ID: Cc: peterz@infradead.org, dzickus@redhat.com, mingo@kernel.org, luto@amacapital.net, davej@redhat.com, torvalds@linux-foundation.org, hpa@zytor.com, linux-kernel@vger.kernel.org, tglx@linutronix.de Reply-To: davej@redhat.com, luto@amacapital.net, linux-kernel@vger.kernel.org, hpa@zytor.com, torvalds@linux-foundation.org, peterz@infradead.org, dzickus@redhat.com, mingo@kernel.org, tglx@linutronix.de In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/urgent] x86, syscall: Fix _TIF_NOHZ handling in syscall_trace_enter_phase1 Git-Commit-ID: b5e212a3051b65e426a513901d9c7001681c7215 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: b5e212a3051b65e426a513901d9c7001681c7215 Gitweb: http://git.kernel.org/tip/b5e212a3051b65e426a513901d9c7001681c7215 Author: Andy Lutomirski AuthorDate: Wed, 19 Nov 2014 13:56:19 -0800 Committer: Thomas Gleixner CommitDate: Thu, 20 Nov 2014 23:01:53 +0100 x86, syscall: Fix _TIF_NOHZ handling in syscall_trace_enter_phase1 TIF_NOHZ is 19 (i.e. _TIF_SYSCALL_TRACE | _TIF_NOTIFY_RESUME | _TIF_SINGLESTEP), not (1<<19). This code is involved in Dave's trinity lockup, but I don't see why it would cause any of the problems he's seeing, except inadvertently by causing a different path through entry_64.S's syscall handling. Signed-off-by: Andy Lutomirski Cc: Don Zickus Cc: Peter Zijlstra Cc: Dave Jones Cc: Linus Torvalds Link: http://lkml.kernel.org/r/a6cd3b60a3f53afb6e1c8081b0ec30ff19003dd7.1416434075.git.luto@amacapital.net Signed-off-by: Thomas Gleixner --- arch/x86/kernel/ptrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index 749b0e4..e510618 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -1484,7 +1484,7 @@ unsigned long syscall_trace_enter_phase1(struct pt_regs *regs, u32 arch) */ if (work & _TIF_NOHZ) { user_exit(); - work &= ~TIF_NOHZ; + work &= ~_TIF_NOHZ; } #ifdef CONFIG_SECCOMP