diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 49bf325325c0..7d14511c20ad 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -5218,6 +5218,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
 	bool adjust_reservation;
 	unsigned long last_addr_mask;
 
+	i_mmap_assert_write_locked(vma->vm_file->f_mapping);
 	WARN_ON(!is_vm_hugetlb_page(vma));
 	BUG_ON(start & ~huge_page_mask(h));
 	BUG_ON(end & ~huge_page_mask(h));
@@ -5309,7 +5310,10 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
 
 		/*
 		 * Restore the reservation for anonymous page, otherwise the
-		 * backing page could be stolen by someone.
+		 * backing page could be stolen by someone. Restore only on the
+		 * last unmap, otherwise the owner could empty its resv map
+		 * while the folio is still mapped by a child. Note that holding
+		 * i_mmap_lock_write is needed to check the number of mappings.
 		 * If there we are freeing a surplus, do not set the restore
 		 * reservation bit.
 		 */
@@ -5317,7 +5321,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
 
 		spin_lock_irq(&hugetlb_lock);
 		if (!h->surplus_huge_pages && __vma_private_lock(vma) &&
-		    folio_test_anon(folio)) {
+		    !folio_mapped(folio) && folio_test_anon(folio)) {
 			folio_set_hugetlb_restore_reserve(folio);
 			/* Reservation to be adjusted after the spin lock */
 			adjust_reservation = true;