diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index d7e125b8d377..46112b50e32d 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -2794,6 +2794,44 @@ pmap_demote_pde_locked(pmap_t pmap, pd_entry_t *pde, vm_offset_t va,
 	return (TRUE);
 }
 
+/*
+ * pmap_remove_kernel_pde: Remove a kernel superpage mapping.
+ */
+static void
+pmap_remove_kernel_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
+{
+	pd_entry_t newpde;
+	vm_paddr_t mptepa;
+	vm_page_t mpte;
+
+	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+	mpte = pmap_lookup_pt_page(pmap, va);
+	if (mpte == NULL)
+		panic("pmap_remove_kernel_pde: Missing pt page.");
+
+	pmap_remove_pt_page(pmap, mpte);
+	mptepa = VM_PAGE_TO_PHYS(mpte);
+	newpde = mptepa | PG_M | PG_A | PG_RW | PG_V;
+
+	/*
+	 * Initialize the page table page.
+	 */
+	pagezero((void *)PHYS_TO_DMAP(mptepa));
+
+	/*
+	 * Demote the mapping.
+	 */
+	if (workaround_erratum383)
+		pmap_update_pde(pmap, va, pde, newpde);
+	else
+		pde_store(pde, newpde);
+
+	/*
+	 * Invalidate a stale recursive mapping of the page table page.
+	 */
+	pmap_invalidate_page(pmap, (vm_offset_t)vtopte(va));
+}
+
 /*
  * pmap_remove_pde: do the things to unmap a superpage in a process
  */
@@ -2837,8 +2875,7 @@ pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
 		}
 	}
 	if (pmap == kernel_pmap) {
-		if (!pmap_demote_pde_locked(pmap, pdq, sva, lockp))
-			panic("pmap_remove_pde: failed demotion");
+		pmap_remove_kernel_pde(pmap, pdq, sva);
 	} else {
 		mpte = pmap_lookup_pt_page(pmap, sva);
 		if (mpte != NULL) {
diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
index 955645805fc7..77b0235a97a9 100644
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -2772,6 +2772,44 @@ pmap_demote_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
 	return (TRUE);
 }
 
+/*
+ * Removes a 2- or 4MB page mapping from the kernel pmap.
+ */
+static void
+pmap_remove_kernel_pde(pmap_t pmap, pd_entry_t *pde, vm_offset_t va)
+{
+	pd_entry_t newpde;
+	vm_paddr_t mptepa;
+	vm_page_t mpte;
+
+	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+	mpte = pmap_lookup_pt_page(pmap, va);
+	if (mpte == NULL)
+		panic("pmap_remove_kernel_pde: Missing pt page.");
+
+	pmap_remove_pt_page(pmap, mpte);
+	mptepa = VM_PAGE_TO_PHYS(mpte);
+	newpde = mptepa | PG_M | PG_A | PG_RW | PG_V;
+
+	/*
+	 * Initialize the page table page.
+	 */
+	pagezero((void *)&KPTmap[i386_btop(trunc_4mpage(va))]);
+
+	/*
+	 * Remove the mapping.
+	 */
+	if (workaround_erratum383)
+		pmap_update_pde(pmap, va, pde, newpde);
+	else 
+		pmap_kenter_pde(va, newpde);
+
+	/*
+	 * Invalidate the recursive mapping of the page table page.
+	 */
+	pmap_invalidate_page(pmap, (vm_offset_t)vtopte(va));
+}
+
 /*
  * pmap_remove_pde: do the things to unmap a superpage in a process
  */
@@ -2814,8 +2852,7 @@ pmap_remove_pde(pmap_t pmap, pd_entry_t *pdq, vm_offset_t sva,
 		}
 	}
 	if (pmap == kernel_pmap) {
-		if (!pmap_demote_pde(pmap, pdq, sva))
-			panic("pmap_remove_pde: failed demotion");
+		pmap_remove_kernel_pde(pmap, pdq, sva);
 	} else {
 		mpte = pmap_lookup_pt_page(pmap, sva);
 		if (mpte != NULL) {