diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index f51dadd1ce43..d9633e5a5ddd 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -884,7 +884,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v)
 		last_vma_end = vma->vm_end;
 	}
 
-	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");