diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index ef18f0d71b11ba6f44c4e6f379328cec875dcdea..8b75a04836b63dc3237bc4b0d44a67691e4e9817 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -951,7 +951,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v)
 		vma = vma->vm_next;
 	}
 
-	show_vma_header_prefix(m, priv->mm->mmap->vm_start,
+	show_vma_header_prefix(m, priv->mm->mmap ? priv->mm->mmap->vm_start : 0,
 			       last_vma_end, 0, 0, 0, 0);
 	seq_pad(m, ' ');
 	seq_puts(m, "[rollup]\n");