mm_for_maps: shift down_read(mmap_sem) to the caller

[mirror_ubuntu-zesty-kernel.git] / fs / proc / task_mmu.c

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 6f61b7cc32e0e09c39aea2dd31cf64e2bc049060..9bd8be1d235c2b420e348d25e801bdce88efd977 100644 (file)
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -119,6 +119,7 @@ static void *m_start(struct seq_file *m, loff_t *pos)
        mm = mm_for_maps(priv->task);
        if (!mm)
                return NULL;
+       down_read(&mm->mmap_sem);
 
        tail_vma = get_gate_vma(priv->task);
        priv->tail_vma = tail_vma;