From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:52708 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752337AbeAaPYa (ORCPT ); Wed, 31 Jan 2018 10:24:30 -0500 Subject: Patch "futex: Fix OWNER_DEAD fixup" has been added to the 4.14-stable tree To: peterz@infradead.org, akpm@linux-foundation.org, davej@codemonkey.org.uk, geert@linux-m68k.org, gregkh@linuxfoundation.org, mingo@kernel.org, paulmck@us.ibm.com, sezeroz@gmail.com, tglx@linutronix.de, torvalds@linux-foundation.org Cc: , From: Date: Wed, 31 Jan 2018 16:24:26 +0100 Message-ID: <151741226637161@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled futex: Fix OWNER_DEAD fixup to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: futex-fix-owner_dead-fixup.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From a97cb0e7b3f4c6297fd857055ae8e895f402f501 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 22 Jan 2018 11:39:47 +0100 Subject: futex: Fix OWNER_DEAD fixup From: Peter Zijlstra commit a97cb0e7b3f4c6297fd857055ae8e895f402f501 upstream. Both Geert and DaveJ reported that the recent futex commit: c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex") introduced a problem with setting OWNER_DEAD. We set the bit on an uninitialized variable and then entirely optimize it away as a dead-store. Move the setting of the bit to where it is more useful. Reported-by: Geert Uytterhoeven Reported-by: Dave Jones Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex") Link: http://lkml.kernel.org/r/20180122103947.GD2228@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar Cc: Ozkan Sezer Signed-off-by: Greg Kroah-Hartman --- kernel/futex.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2311,9 +2311,6 @@ static int fixup_pi_state_owner(u32 __us raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); oldowner = pi_state->owner; - /* Owner died? */ - if (!pi_state->owner) - newtid |= FUTEX_OWNER_DIED; /* * We are here because either: @@ -2374,6 +2371,9 @@ retry: } newtid = task_pid_vnr(newowner) | FUTEX_WAITERS; + /* Owner died? */ + if (!pi_state->owner) + newtid |= FUTEX_OWNER_DIED; if (get_futex_value_locked(&uval, uaddr)) goto handle_fault; Patches currently in stable-queue which might be from peterz@infradead.org are queue-4.14/futex-fix-owner_dead-fixup.patch