1 files changed, 19 insertions, 9 deletions

diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 74c5d9a3afae..3bdb44bde4b7 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -44,6 +44,10 @@ static inline void check_stack(void)
         if (this_size <= max_stack_size)
                 return;
 
+        /* we do not handle interrupt stacks yet */
+        if (!object_is_on_stack(&this_size))
+                return;
+
         raw_local_irq_save(flags);
         __raw_spin_lock(&max_stack_lock);
 
@@ -180,11 +184,16 @@ static struct file_operations stack_max_size_fops = {
 static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
-        long i = (long)m->private;
+        long i;
 
         (*pos)++;
 
-        i++;
+        if (v == SEQ_START_TOKEN)
+                i = 0;
+        else {
+                i = *(long *)v;
+                i++;
+        }
 
         if (i >= max_stack_trace.nr_entries ||
             stack_dump_trace[i] == ULONG_MAX)
@@ -197,12 +206,15 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
-        void *t = &m->private;
+        void *t = SEQ_START_TOKEN;
         loff_t l = 0;
 
         local_irq_disable();
         __raw_spin_lock(&max_stack_lock);
 
+        if (*pos == 0)
+                return SEQ_START_TOKEN;
+
         for (; t && l < *pos; t = t_next(m, t, &l))
                 ;
 
@@ -231,10 +243,10 @@ static int trace_lookup_stack(struct seq_file *m, long i)
 
 static int t_show(struct seq_file *m, void *v)
 {
-        long i = *(long *)v;
+        long i;
         int size;
 
-        if (i < 0) {
+        if (v == SEQ_START_TOKEN) {
                 seq_printf(m, "        Depth   Size      Location"
                            "    (%d entries)\n"
                            "        -----   ----      --------\n",
@@ -242,6 +254,8 @@ static int t_show(struct seq_file *m, void *v)
                 return 0;
         }
 
+        i = *(long *)v;
+
         if (i >= max_stack_trace.nr_entries ||
             stack_dump_trace[i] == ULONG_MAX)
                 return 0;
@@ -271,10 +285,6 @@ static int stack_trace_open(struct inode *inode, struct file *file)
         int ret;
 
         ret = seq_open(file, &stack_trace_seq_ops);
-        if (!ret) {
-                struct seq_file *m = file->private_data;
-                m->private = (void *)-1;
-        }
 
         return ret;
 }