Merge 4.4.255 into android-4.4-p

Changes in 4.4.255
	ACPI: sysfs: Prefer "compatible" modalias
	wext: fix NULL-ptr-dereference with cfg80211's lack of commit()
	net: usb: qmi_wwan: added support for Thales Cinterion PLSx3 modem family
	KVM: x86/pmu: Fix HW_REF_CPU_CYCLES event pseudo-encoding in intel_arch_events[]
	mt7601u: fix kernel crash unplugging the device
	mt7601u: fix rx buffer refcounting
	y2038: futex: Move compat implementation into futex.c
	futex: Move futex exit handling into futex code
	futex: Replace PF_EXITPIDONE with a state
	exit/exec: Seperate mm_release()
	futex: Split futex_mm_release() for exit/exec
	futex: Set task::futex_state to DEAD right after handling futex exit
	futex: Mark the begin of futex exit explicitly
	futex: Sanitize exit state handling
	futex: Provide state handling for exec() as well
	futex: Add mutex around futex exit
	futex: Provide distinct return value when owner is exiting
	futex: Prevent exit livelock
	ARM: imx: build suspend-imx6.S with arm instruction set
	netfilter: nft_dynset: add timeout extension to template
	xfrm: Fix oops in xfrm_replay_advance_bmp
	RDMA/cxgb4: Fix the reported max_recv_sge value
	mac80211: pause TX while changing interface type
	can: dev: prevent potential information leak in can_fill_info()
	iommu/vt-d: Gracefully handle DMAR units with no supported address widths
	iommu/vt-d: Don't dereference iommu_device if IOMMU_API is not built
	NFC: fix resource leak when target index is invalid
	NFC: fix possible resource leak
	Linux 4.4.255

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I33bac27670b3cd649e2c8c1ce42efff148f8f202

1 files changed, 15 insertions, 25 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index f7e3c2721238..56fda05f5137 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -914,24 +914,8 @@ static int wait_for_vfork_done(struct task_struct *child,
  * restoring the old one. . .
  * Eric Biederman 10 January 1998
  */
-void mm_release(struct task_struct *tsk, struct mm_struct *mm)
+static void mm_release(struct task_struct *tsk, struct mm_struct *mm)
 {
-	/* Get rid of any futexes when releasing the mm */
-#ifdef CONFIG_FUTEX
-	if (unlikely(tsk->robust_list)) {
-		exit_robust_list(tsk);
-		tsk->robust_list = NULL;
-	}
-#ifdef CONFIG_COMPAT
-	if (unlikely(tsk->compat_robust_list)) {
-		compat_exit_robust_list(tsk);
-		tsk->compat_robust_list = NULL;
-	}
-#endif
-	if (unlikely(!list_empty(&tsk->pi_state_list)))
-		exit_pi_state_list(tsk);
-#endif
-
 	uprobe_free_utask(tsk);
 
 	/* Get rid of any cached register state */
@@ -964,6 +948,18 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
 		complete_vfork_done(tsk);
 }
 
+void exit_mm_release(struct task_struct *tsk, struct mm_struct *mm)
+{
+	futex_exit_release(tsk);
+	mm_release(tsk, mm);
+}
+
+void exec_mm_release(struct task_struct *tsk, struct mm_struct *mm)
+{
+	futex_exec_release(tsk);
+	mm_release(tsk, mm);
+}
+
 /*
  * Allocate a new mm structure and copy contents from the
  * mm structure of the passed in task structure.
@@ -1540,14 +1536,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 #ifdef CONFIG_BLOCK
 	p->plug = NULL;
 #endif
-#ifdef CONFIG_FUTEX
-	p->robust_list = NULL;
-#ifdef CONFIG_COMPAT
-	p->compat_robust_list = NULL;
-#endif
-	INIT_LIST_HEAD(&p->pi_state_list);
-	p->pi_state_cache = NULL;
-#endif
+	futex_init_task(p);
+
 	/*
 	 * sigaltstack should be cleared when sharing the same VM
 	 */