Merge tag 'v3.5-rc4' into drm-intel-next-queueddrm-intel-next-2012-06-21-merged

I want to merge the "no more fake agp on gen6+" patches into
drm-intel-next (well, the last pieces). But a patch in 3.5-rc4 also
adds a new use of dev->agp. Hence the backmarge to sort this out, for
otherwise drm-intel-next merged into Linus' tree would conflict in the
relevant code, things would compile but nicely OOPS at driver load :(

Conflicts in this merge are just simple cases of "both branches
changed/added lines at the same place". The only tricky part is to
keep the order correct wrt the unwind code in case of errors in
intel_ringbuffer.c (and the MI_DISPLAY_FLIP #defines in i915_reg.h
together, obviously).

Conflicts:
	drivers/gpu/drm/i915/i915_reg.h
	drivers/gpu/drm/i915/intel_ringbuffer.c

Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 31 insertions, 2 deletions

diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 57bc1fd35b3..b3c7fd55425 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -149,7 +149,12 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
 {
 	int nr;
 	int rc;
-	struct task_struct *task;
+	struct task_struct *task, *me = current;
+
+	/* Ignore SIGCHLD causing any terminated children to autoreap */
+	spin_lock_irq(&me->sighand->siglock);
+	me->sighand->action[SIGCHLD - 1].sa.sa_handler = SIG_IGN;
+	spin_unlock_irq(&me->sighand->siglock);
 
 	/*
 	 * The last thread in the cgroup-init thread group is terminating.
@@ -179,11 +184,31 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
 	}
 	read_unlock(&tasklist_lock);
 
+	/* Firstly reap the EXIT_ZOMBIE children we may have. */
 	do {
 		clear_thread_flag(TIF_SIGPENDING);
 		rc = sys_wait4(-1, NULL, __WALL, NULL);
 	} while (rc != -ECHILD);
 
+	/*
+	 * sys_wait4() above can't reap the TASK_DEAD children.
+	 * Make sure they all go away, see __unhash_process().
+	 */
+	for (;;) {
+		bool need_wait = false;
+
+		read_lock(&tasklist_lock);
+		if (!list_empty(&current->children)) {
+			__set_current_state(TASK_UNINTERRUPTIBLE);
+			need_wait = true;
+		}
+		read_unlock(&tasklist_lock);
+
+		if (!need_wait)
+			break;
+		schedule();
+	}
+
 	if (pid_ns->reboot)
 		current->signal->group_exit_code = pid_ns->reboot;
 
@@ -191,6 +216,7 @@ void zap_pid_ns_processes(struct pid_namespace *pid_ns)
 	return;
 }
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
 static int pid_ns_ctl_handler(struct ctl_table *table, int write,
 		void __user *buffer, size_t *lenp, loff_t *ppos)
 {
@@ -218,8 +244,8 @@ static struct ctl_table pid_ns_ctl_table[] = {
 	},
 	{ }
 };
-
 static struct ctl_path kern_path[] = { { .procname = "kernel", }, { } };
+#endif	/* CONFIG_CHECKPOINT_RESTORE */
 
 int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
 {
@@ -253,7 +279,10 @@ int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
 static __init int pid_namespaces_init(void)
 {
 	pid_ns_cachep = KMEM_CACHE(pid_namespace, SLAB_PANIC);
+
+#ifdef CONFIG_CHECKPOINT_RESTORE
 	register_sysctl_paths(kern_path, pid_ns_ctl_table);
+#endif
 	return 0;
 }