3 files changed, 22 insertions, 13 deletions

diff --git a/kernel/printk.c b/kernel/printk.c
index 357f714ddd49..267ce780abe8 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -87,12 +87,6 @@ static DEFINE_SEMAPHORE(console_sem);
 struct console *console_drivers;
 EXPORT_SYMBOL_GPL(console_drivers);
 
-#ifdef CONFIG_LOCKDEP
-static struct lockdep_map console_lock_dep_map = {
-        .name = "console_lock"
-};
-#endif
-
 /*
  * This is used for debugging the mess that is the VT code by
  * keeping track if we have the console semaphore held. It's
@@ -1924,7 +1918,6 @@ void console_lock(void)
                 return;
         console_locked = 1;
         console_may_schedule = 1;
-        mutex_acquire(&console_lock_dep_map, 0, 0, _RET_IP_);
 }
 EXPORT_SYMBOL(console_lock);
 
@@ -1946,7 +1939,6 @@ int console_trylock(void)
         }
         console_locked = 1;
         console_may_schedule = 0;
-        mutex_acquire(&console_lock_dep_map, 0, 1, _RET_IP_);
         return 1;
 }
 EXPORT_SYMBOL(console_trylock);
@@ -2107,7 +2099,6 @@ skip:
                 local_irq_restore(flags);
         }
         console_locked = 0;
-        mutex_release(&console_lock_dep_map, 1, _RET_IP_);
 
         /* Release the exclusive_console once it is used */
         if (unlikely(exclusive_console))
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index f6e5ec2932b4..c1cc7e17ff9d 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -40,8 +40,7 @@
 #ifdef CONFIG_RCU_NOCB_CPU
 static cpumask_var_t rcu_nocb_mask; /* CPUs to have callbacks offloaded. */
 static bool have_rcu_nocb_mask;     /* Was rcu_nocb_mask allocated? */
-static bool rcu_nocb_poll;          /* Offload kthread are to poll. */
-module_param(rcu_nocb_poll, bool, 0444);
+static bool __read_mostly rcu_nocb_poll;    /* Offload kthread are to poll. */
 static char __initdata nocb_buf[NR_CPUS * 5];
 #endif /* #ifdef CONFIG_RCU_NOCB_CPU */
 
@@ -2159,6 +2158,13 @@ static int __init rcu_nocb_setup(char *str)
 }
 __setup("rcu_nocbs=", rcu_nocb_setup);
 
+static int __init parse_rcu_nocb_poll(char *arg)
+{
+        rcu_nocb_poll = 1;
+        return 0;
+}
+early_param("rcu_nocb_poll", parse_rcu_nocb_poll);
+
 /* Is the specified CPU a no-CPUs CPU? */
 static bool is_nocb_cpu(int cpu)
 {
@@ -2366,10 +2372,11 @@ static int rcu_nocb_kthread(void *arg)
         for (;;) {
                 /* If not polling, wait for next batch of callbacks. */
                 if (!rcu_nocb_poll)
-                        wait_event(rdp->nocb_wq, rdp->nocb_head);
+                        wait_event_interruptible(rdp->nocb_wq, rdp->nocb_head);
                 list = ACCESS_ONCE(rdp->nocb_head);
                 if (!list) {
                         schedule_timeout_interruptible(1);
+                        flush_signals(current);
                         continue;
                 }
 
diff --git a/kernel/smp.c b/kernel/smp.c
index 29dd40a9f2f4..69f38bd98b42 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -33,6 +33,7 @@ struct call_function_data {
         struct call_single_data csd;
         atomic_t                refs;
         cpumask_var_t           cpumask;
+        cpumask_var_t           cpumask_ipi;
 };
 
 static DEFINE_PER_CPU_SHARED_ALIGNED(struct call_function_data, cfd_data);
@@ -56,6 +57,9 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
                 if (!zalloc_cpumask_var_node(&cfd->cpumask, GFP_KERNEL,
                                 cpu_to_node(cpu)))
                         return notifier_from_errno(-ENOMEM);
+                if (!zalloc_cpumask_var_node(&cfd->cpumask_ipi, GFP_KERNEL,
+                                cpu_to_node(cpu)))
+                        return notifier_from_errno(-ENOMEM);
                 break;
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -65,6 +69,7 @@ hotplug_cfd(struct notifier_block *nfb, unsigned long action, void *hcpu)
         case CPU_DEAD:
         case CPU_DEAD_FROZEN:
                 free_cpumask_var(cfd->cpumask);
+                free_cpumask_var(cfd->cpumask_ipi);
                 break;
 #endif
         };
@@ -526,6 +531,12 @@ void smp_call_function_many(const struct cpumask *mask,
                 return;
         }
 
+        /*
+         * After we put an entry into the list, data->cpumask
+         * may be cleared again when another CPU sends another IPI for
+         * a SMP function call, so data->cpumask will be zero.
+         */
+        cpumask_copy(data->cpumask_ipi, data->cpumask);
         raw_spin_lock_irqsave(&call_function.lock, flags);
         /*
          * Place entry at the _HEAD_ of the list, so that any cpu still
@@ -549,7 +560,7 @@ void smp_call_function_many(const struct cpumask *mask,
         smp_mb();
 
         /* Send a message to all CPUs in the map */
-        arch_send_call_function_ipi_mask(data->cpumask);
+        arch_send_call_function_ipi_mask(data->cpumask_ipi);
 
         /* Optionally wait for the CPUs to complete */
         if (wait)