1 files changed, 13 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 71c0b6f98a62..1416485e278c 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1513,8 +1513,20 @@ void zap_page_range(struct vm_area_struct *vma, unsigned long start,
 	tlb_gather_mmu(&tlb, mm, start, end);
 	update_hiwater_rss(mm);
 	mmu_notifier_invalidate_range_start(mm, start, end);
-	for ( ; vma && vma->vm_start < end; vma = vma->vm_next)
+	for ( ; vma && vma->vm_start < end; vma = vma->vm_next) {
 		unmap_single_vma(&tlb, vma, start, end, NULL);
+
+		/*
+		 * zap_page_range does not specify whether mmap_sem should be
+		 * held for read or write. That allows parallel zap_page_range
+		 * operations to unmap a PTE and defer a flush meaning that
+		 * this call observes pte_none and fails to flush the TLB.
+		 * Rather than adding a complex API, ensure that no stale
+		 * TLB entries exist when this call returns.
+		 */
+		flush_tlb_range(vma, start, end);
+	}
+
 	mmu_notifier_invalidate_range_end(mm, start, end);
 	tlb_finish_mmu(&tlb, start, end);
 }