Index: sys/kern/kern_exec.c
===================================================================
--- sys/kern/kern_exec.c
+++ sys/kern/kern_exec.c
@@ -981,8 +981,10 @@
 	if (ma[0]->valid != VM_PAGE_BITS_ALL) {
 		vm_page_xbusy(ma[0]);
 		if (!vm_pager_has_page(object, 0, NULL, &after)) {
-			vm_page_unwire_noq(ma[0]);
-			vm_page_free(ma[0]);
+			if (vm_page_unwire_noq(ma[0]))
+				vm_page_free(ma[0]);
+			else
+				vm_page_xunbusy(ma[0]);
 			VM_OBJECT_WUNLOCK(object);
 			return (EIO);
 		}
@@ -1006,9 +1008,21 @@
 		initial_pagein = i;
 		rv = vm_pager_get_pages(object, ma, initial_pagein, NULL, NULL);
 		if (rv != VM_PAGER_OK) {
-			vm_page_unwire_noq(ma[0]);
-			for (i = 0; i < initial_pagein; i++)
-				vm_page_free(ma[i]);
+			if (vm_page_unwire_noq(ma[0]))
+				vm_page_free(ma[0]);
+			else
+				vm_page_xunbusy(ma[i]);
+			for (i = 1; i < initial_pagein; i++) {
+				/*
+				 * New wirings cannot be created while the
+				 * object is locked and the page is exclusively
+				 * busied.
+				 */
+				if (!vm_page_wired(ma[i]))
+					vm_page_free(ma[i]);
+				else
+					vm_page_xunbusy(ma[i]);
+			}
 			VM_OBJECT_WUNLOCK(object);
 			return (EIO);
 		}