6 files changed, 34 insertions, 14 deletions

diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index 8a5c7d55ac9f..967e66143e11 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -360,8 +360,8 @@ EXPORT_SYMBOL_GPL(register_user_hw_breakpoint);
 int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr)
 {
         u64 old_addr = bp->attr.bp_addr;
+        u64 old_len = bp->attr.bp_len;
         int old_type = bp->attr.bp_type;
-        int old_len = bp->attr.bp_len;
         int err = 0;
 
         perf_event_disable(bp);
diff --git a/kernel/kfifo.c b/kernel/kfifo.c
index 498cabba225e..35edbe22e9a9 100644
--- a/kernel/kfifo.c
+++ b/kernel/kfifo.c
@@ -80,7 +80,7 @@ int kfifo_alloc(struct kfifo *fifo, unsigned int size, gfp_t gfp_mask)
 
         buffer = kmalloc(size, gfp_mask);
         if (!buffer) {
-                _kfifo_init(fifo, 0, 0);
+                _kfifo_init(fifo, NULL, 0);
                 return -ENOMEM;
         }
 
@@ -97,6 +97,7 @@ EXPORT_SYMBOL(kfifo_alloc);
 void kfifo_free(struct kfifo *fifo)
 {
         kfree(fifo->buffer);
+        _kfifo_init(fifo, NULL, 0);
 }
 EXPORT_SYMBOL(kfifo_free);
 
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index d27746bd3a06..2b19297742cb 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -4580,7 +4580,7 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
         if (attr->type >= PERF_TYPE_MAX)
                 return -EINVAL;
 
-        if (attr->__reserved_1 || attr->__reserved_2)
+        if (attr->__reserved_1)
                 return -EINVAL;
 
         if (attr->sample_type & ~(PERF_SAMPLE_MAX-1))
diff --git a/kernel/softirq.c b/kernel/softirq.c
index a09502e2ef75..7c1a67ef0274 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -500,22 +500,17 @@ EXPORT_SYMBOL(tasklet_kill);
  */
 
 /*
- * The trampoline is called when the hrtimer expires. If this is
- * called from the hrtimer interrupt then we schedule the tasklet as
- * the timer callback function expects to run in softirq context. If
- * it's called in softirq context anyway (i.e. high resolution timers
- * disabled) then the hrtimer callback is called right away.
+ * The trampoline is called when the hrtimer expires. It schedules a tasklet
+ * to run __tasklet_hrtimer_trampoline() which in turn will call the intended
+ * hrtimer callback, but from softirq context.
  */
 static enum hrtimer_restart __hrtimer_tasklet_trampoline(struct hrtimer *timer)
 {
         struct tasklet_hrtimer *ttimer =
                 container_of(timer, struct tasklet_hrtimer, timer);
 
-        if (hrtimer_is_hres_active(timer)) {
-                tasklet_hi_schedule(&ttimer->tasklet);
-                return HRTIMER_NORESTART;
-        }
-        return ttimer->function(timer);
+        tasklet_hi_schedule(&ttimer->tasklet);
+        return HRTIMER_NORESTART;
 }
 
 /*
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 6ea90c0e2c96..50b1b8239806 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -689,7 +689,7 @@ static int create_trace_probe(int argc, char **argv)
                         return -EINVAL;
                 }
                 /* an address specified */
-                ret = strict_strtoul(&argv[0][2], 0, (unsigned long *)&addr);
+                ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr);
                 if (ret) {
                         pr_info("Failed to parse address.\n");
                         return ret;
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 678a5120ee30..f4bc9b27de5f 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -157,6 +157,7 @@ stack_max_size_write(struct file *filp, const char __user *ubuf,
         unsigned long val, flags;
         char buf[64];
         int ret;
+        int cpu;
 
         if (count >= sizeof(buf))
                 return -EINVAL;
@@ -171,9 +172,20 @@ stack_max_size_write(struct file *filp, const char __user *ubuf,
                 return ret;
 
         local_irq_save(flags);
+
+        /*
+         * In case we trace inside arch_spin_lock() or after (NMI),
+         * we will cause circular lock, so we also need to increase
+         * the percpu trace_active here.
+         */
+        cpu = smp_processor_id();
+        per_cpu(trace_active, cpu)++;
+
         arch_spin_lock(&max_stack_lock);
         *ptr = val;
         arch_spin_unlock(&max_stack_lock);
+
+        per_cpu(trace_active, cpu)--;
         local_irq_restore(flags);
 
         return count;
@@ -206,7 +218,13 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
+        int cpu;
+
         local_irq_disable();
+
+        cpu = smp_processor_id();
+        per_cpu(trace_active, cpu)++;
+
         arch_spin_lock(&max_stack_lock);
 
         if (*pos == 0)
@@ -217,7 +235,13 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 
 static void t_stop(struct seq_file *m, void *p)
 {
+        int cpu;
+
         arch_spin_unlock(&max_stack_lock);
+
+        cpu = smp_processor_id();
+        per_cpu(trace_active, cpu)--;
+
         local_irq_enable();
 }