Index: sys/compat/linux/linux_mmap.c
===================================================================
--- sys/compat/linux/linux_mmap.c
+++ sys/compat/linux/linux_mmap.c
@@ -176,7 +176,7 @@
 			 * mmap's return value.
 			 */
 			PROC_LOCK(p);
-			vms->vm_maxsaddr = (char *)p->p_sysent->sv_usrstack -
+			vms->vm_maxsaddr = (char *)vms->vm_stacktop -
 			    lim_cur_proc(p, RLIMIT_STACK);
 			PROC_UNLOCK(p);
 		}
Index: sys/kern/kern_resource.c
===================================================================
--- sys/kern/kern_resource.c
+++ sys/kern/kern_resource.c
@@ -760,12 +760,12 @@
 			if (limp->rlim_cur > oldssiz.rlim_cur) {
 				prot = p->p_sysent->sv_stackprot;
 				size = limp->rlim_cur - oldssiz.rlim_cur;
-				addr = p->p_sysent->sv_usrstack -
+				addr = p->p_vmspace->vm_stacktop -
 				    limp->rlim_cur;
 			} else {
 				prot = VM_PROT_NONE;
 				size = oldssiz.rlim_cur - limp->rlim_cur;
-				addr = p->p_sysent->sv_usrstack -
+				addr = p->p_vmspace->vm_stacktop -
 				    oldssiz.rlim_cur;
 			}
 			addr = trunc_page(addr);
Index: sys/vm/vm_map.c
===================================================================
--- sys/vm/vm_map.c
+++ sys/vm/vm_map.c
@@ -4664,7 +4664,7 @@
 	 * limit.
 	 */
 	is_procstack = addr >= (vm_offset_t)vm->vm_maxsaddr &&
-	    addr < (vm_offset_t)p->p_sysent->sv_usrstack;
+	    addr < (vm_offset_t)vm->vm_stacktop;
 	if (is_procstack && (ctob(vm->vm_ssize) + grow_amount > stacklim))
 		return (KERN_NO_SPACE);