Merge tag 'arc-4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

[cascardo/linux.git] / fs / proc / task_mmu.c

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index f6fa99e..35b92d8 100644 (file)
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -147,7 +147,7 @@ m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
 static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
 {
        if (m->count < m->size) /* vma is copied successfully */
-               m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
+               m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
 }
 
 static void *m_start(struct seq_file *m, loff_t *ppos)
@@ -175,8 +175,10 @@ static void *m_start(struct seq_file *m, loff_t *ppos)
        priv->tail_vma = get_gate_vma(mm);
 
        if (last_addr) {
-               vma = find_vma(mm, last_addr);
-               if (vma && (vma = m_next_vma(priv, vma)))
+               vma = find_vma(mm, last_addr - 1);
+               if (vma && vma->vm_start <= last_addr)
+                       vma = m_next_vma(priv, vma);
+               if (vma)
                        return vma;
        }
 
@@ -264,24 +266,15 @@ static int do_maps_open(struct inode *inode, struct file *file,
  * /proc/PID/maps that is the stack of the main task.
  */
 static int is_stack(struct proc_maps_private *priv,
-                   struct vm_area_struct *vma, int is_pid)
+                   struct vm_area_struct *vma)
 {
-       int stack = 0;
-
-       if (is_pid) {
-               stack = vma->vm_start <= vma->vm_mm->start_stack &&
-                       vma->vm_end >= vma->vm_mm->start_stack;
-       } else {
-               struct inode *inode = priv->inode;
-               struct task_struct *task;
-
-               rcu_read_lock();
-               task = pid_task(proc_pid(inode), PIDTYPE_PID);
-               if (task)
-                       stack = vma_is_stack_for_task(vma, task);
-               rcu_read_unlock();
-       }
-       return stack;
+       /*
+        * We make no effort to guess what a given thread considers to be
+        * its "stack".  It's not even well-defined for programs written
+        * languages like Go.
+        */
+       return vma->vm_start <= vma->vm_mm->start_stack &&
+               vma->vm_end >= vma->vm_mm->start_stack;
 }
 
 static void
@@ -352,7 +345,7 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
                        goto done;
                }
 
-               if (is_stack(priv, vma, is_pid))
+               if (is_stack(priv, vma))
                        name = "[stack]";
        }
 
@@ -1070,7 +1063,7 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
                        }
                        mmu_notifier_invalidate_range_start(mm, 0, -1);
                }
-               walk_page_range(0, ~0UL, &clear_refs_walk);
+               walk_page_range(0, mm->highest_vm_end, &clear_refs_walk);
                if (type == CLEAR_REFS_SOFT_DIRTY)
                        mmu_notifier_invalidate_range_end(mm, 0, -1);
                flush_tlb_mm(mm);
@@ -1667,7 +1660,7 @@ static int show_numa_map(struct seq_file *m, void *v, int is_pid)
                seq_file_path(m, file, "\n\t= ");
        } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
                seq_puts(m, " heap");
-       } else if (is_stack(proc_priv, vma, is_pid)) {
+       } else if (is_stack(proc_priv, vma)) {
                seq_puts(m, " stack");
        }