diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 80bb700..cf43261 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -115,7 +115,12 @@ static int elf_legacy_coredump = 0;
 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW, 
     &elf_legacy_coredump, 0, "");
 
-static int __elfN(nxstack) = 0;
+static int __elfN(nxstack) =
+#if defined(__amd64__) || defined(__powerpc__) /* both 64 and 32 bit */
+	1;
+#else
+	0;
+#endif
 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO,
     nxstack, CTLFLAG_RW, &__elfN(nxstack), 0,
     __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack");
diff --git a/sys/kern/kern_exec.c b/sys/kern/kern_exec.c
index c51cc39..2704bf1 100644
--- a/sys/kern/kern_exec.c
+++ b/sys/kern/kern_exec.c
@@ -1486,63 +1486,53 @@ exec_unregister(execsw_arg)
 	return (0);
 }
 
-static vm_object_t shared_page_obj;
-static int shared_page_free;
-
 int
-shared_page_fill(int size, int align, const char *data)
+shared_page_fill(struct sysentvec *sv, int size, int align, const char *data)
 {
+	vm_object_t obj;
 	vm_page_t m;
 	struct sf_buf *s;
 	vm_offset_t sk;
 	int res;
 
-	VM_OBJECT_LOCK(shared_page_obj);
-	m = vm_page_grab(shared_page_obj, 0, VM_ALLOC_RETRY);
-	res = roundup(shared_page_free, align);
-	if (res + size >= IDX_TO_OFF(shared_page_obj->size))
+	obj = sv->sv_shared_page_obj;
+	VM_OBJECT_LOCK(obj);
+	m = vm_page_grab(obj, 0, VM_ALLOC_RETRY);
+	res = roundup(sv->sv_shared_page_free, align);
+	if (res + size >= IDX_TO_OFF(obj->size))
 		res = -1;
 	else {
-		VM_OBJECT_UNLOCK(shared_page_obj);
+		VM_OBJECT_UNLOCK(obj);
 		s = sf_buf_alloc(m, SFB_DEFAULT);
 		sk = sf_buf_kva(s);
 		bcopy(data, (void *)(sk + res), size);
-		shared_page_free = res + size;
+		sv->sv_shared_page_free = res + size;
 		sf_buf_free(s);
-		VM_OBJECT_LOCK(shared_page_obj);
+		VM_OBJECT_LOCK(obj);
 	}
 	vm_page_wakeup(m);
-	VM_OBJECT_UNLOCK(shared_page_obj);
+	VM_OBJECT_UNLOCK(obj);
 	return (res);
 }
 
-static void
-shared_page_init(void *dummy __unused)
-{
-	vm_page_t m;
-
-	shared_page_obj = vm_pager_allocate(OBJT_PHYS, 0, PAGE_SIZE,
-	    VM_PROT_DEFAULT, 0, NULL);
-	VM_OBJECT_LOCK(shared_page_obj);
-	m = vm_page_grab(shared_page_obj, 0, VM_ALLOC_RETRY | VM_ALLOC_NOBUSY |
-	    VM_ALLOC_ZERO);
-	m->valid = VM_PAGE_BITS_ALL;
-	VM_OBJECT_UNLOCK(shared_page_obj);
-}
-
-SYSINIT(shp, SI_SUB_EXEC, SI_ORDER_FIRST, (sysinit_cfunc_t)shared_page_init,
-    NULL);
-
 void
 exec_sysvec_init(void *param)
 {
+	vm_object_t obj;
+	vm_page_t m;
 	struct sysentvec *sv;
 
 	sv = (struct sysentvec *)param;
-
-	if ((sv->sv_flags & SV_SHP) == 0)
+	if ((sv->sv_flags & SV_SHP) == 0 || sv->sv_shared_page_obj != NULL)
 		return;
-	sv->sv_shared_page_obj = shared_page_obj;
+
+	obj = sv->sv_shared_page_obj = vm_pager_allocate(OBJT_PHYS, 0,
+	    PAGE_SIZE, VM_PROT_DEFAULT, 0, NULL);
+	VM_OBJECT_LOCK(obj);
+	m = vm_page_grab(obj, 0, VM_ALLOC_RETRY | VM_ALLOC_NOBUSY |
+	    VM_ALLOC_ZERO);
+	m->valid = VM_PAGE_BITS_ALL;
+	VM_OBJECT_UNLOCK(obj);
 	sv->sv_sigcode_base = sv->sv_shared_page_base +
-	    shared_page_fill(*(sv->sv_szsigcode), 16, sv->sv_sigcode);
+	    shared_page_fill(sv, *(sv->sv_szsigcode), 16, sv->sv_sigcode);
 }
diff --git a/sys/sys/sysent.h b/sys/sys/sysent.h
index 90bce21..99afd13 100644
--- a/sys/sys/sysent.h
+++ b/sys/sys/sysent.h
@@ -125,6 +125,7 @@ struct sysentvec {
 	vm_offset_t	sv_shared_page_len;
 	vm_offset_t	sv_sigcode_base;
 	void		*sv_shared_page_obj;
+	int		sv_shared_page_free;
 	void		(*sv_schedtail)(struct thread *);
 };
 
@@ -235,7 +236,8 @@ int	lkmressys(struct thread *, struct nosys_args *);
 int	syscall_thread_enter(struct thread *td, struct sysent *se);
 void	syscall_thread_exit(struct thread *td, struct sysent *se);
 
-int shared_page_fill(int size, int align, const char *data);
+int shared_page_fill(struct sysentvec *sv, int size, int align,
+    const char *data);
 void exec_sysvec_init(void *param);
 
 #define INIT_SYSENTVEC(name, sv)					\