--- /dev/null
+From a97cb0e7b3f4c6297fd857055ae8e895f402f501 Mon Sep 17 00:00:00 2001
+From: Peter Zijlstra <peterz@infradead.org>
+Date: Mon, 22 Jan 2018 11:39:47 +0100
+Subject: futex: Fix OWNER_DEAD fixup
+
+From: Peter Zijlstra <peterz@infradead.org>
+
+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 <geert@linux-m68k.org>
+Reported-by: Dave Jones <davej@codemonkey.org.uk>
+Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
+Cc: Andrew Morton <akpm@linux-foundation.org>
+Cc: Linus Torvalds <torvalds@linux-foundation.org>
+Cc: Paul E. McKenney <paulmck@us.ibm.com>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+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 <mingo@kernel.org>
+Cc: Ozkan Sezer <sezeroz@gmail.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ 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;