diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index f2481cb..195de42 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -244,11 +244,21 @@
 	 */
 	VIRTUAL_BUG_ON(!is_vmalloc_or_module_addr(vmalloc_addr));
 
+	/*
+	 * Don't dereference bad PUD or PMD (below) entries. This will also
+	 * identify huge mappings, which we may encounter on architectures
+	 * that define CONFIG_HAVE_ARCH_HUGE_VMAP=y. Such regions will be
+	 * identified as vmalloc addresses by is_vmalloc_addr(), but are
+	 * not [unambiguously] associated with a struct page, so there is
+	 * no correct value to return for them.
+	 */
 	if (!pgd_none(*pgd)) {
 		pud_t *pud = pud_offset(pgd, addr);
-		if (!pud_none(*pud)) {
+		WARN_ON_ONCE(pud_bad(*pud));
+		if (!pud_none(*pud) && !pud_bad(*pud)) {
 			pmd_t *pmd = pmd_offset(pud, addr);
-			if (!pmd_none(*pmd)) {
+			WARN_ON_ONCE(pmd_bad(*pmd));
+			if (!pmd_none(*pmd) && !pmd_bad(*pmd)) {
 				pte_t *ptep, pte;
 
 				ptep = pte_offset_map(pmd, addr);