Assigning list pointers doesn't really work with doubly linked lists. Use

a remove-and-insert-all-items approach for now and remove the comments that
suggest manipulating list pointers.  Pointed out by Pedro Martelletto.

ok beck@, krw@, mikeb@

diff --git a/sys/uvm/uvm_aobj.c b/sys/uvm/uvm_aobj.c
index 5e900b6..6249c85 100644 (file)
--- a/sys/uvm/uvm_aobj.c
+++ b/sys/uvm/uvm_aobj.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: uvm_aobj.c,v 1.61 2014/04/13 23:14:15 tedu Exp $      */
+/*     $OpenBSD: uvm_aobj.c,v 1.62 2014/04/30 16:07:31 kettenis Exp $  */
 /*     $NetBSD: uvm_aobj.c,v 1.39 2001/02/18 21:19:08 chs Exp $        */
 
 /*
@@ -431,6 +431,7 @@ uao_shrink_hash(struct uvm_object *uobj, int pages)
 {
        struct uvm_aobj *aobj = (struct uvm_aobj *)uobj;
        struct uao_swhash *new_swhash;
+       struct uao_swhash_elt *elt;
        unsigned long new_hashmask;
        int i;
 
@@ -456,8 +457,13 @@ uao_shrink_hash(struct uvm_object *uobj, int pages)
         * Even though the hash table size is changing, the hash of the buckets
         * we are interested in copying should not change.
         */
-       for (i = 0; i < UAO_SWHASH_BUCKETS(aobj->u_pages); i++)
-               LIST_FIRST(&new_swhash[i]) = LIST_FIRST(&aobj->u_swhash[i]);
+       for (i = 0; i < UAO_SWHASH_BUCKETS(aobj->u_pages); i++) {
+               while (LIST_EMPTY(&aobj->u_swhash[i]) == 0) {
+                       elt = LIST_FIRST(&aobj->u_swhash[i]);
+                       LIST_REMOVE(elt, list);
+                       LIST_INSERT_HEAD(&new_swhash[i], elt, list);
+               }
+       }
 
        free(aobj->u_swhash, M_UVMAOBJ);
 
@@ -609,7 +615,6 @@ uao_grow_hash(struct uvm_object *uobj, int pages)
                return ENOMEM;
 
        for (i = 0; i < UAO_SWHASH_BUCKETS(aobj->u_pages); i++) {
-               /* XXX pedro: shouldn't copying the list pointers be enough? */
                while (LIST_EMPTY(&aobj->u_swhash[i]) == 0) {
                        elt = LIST_FIRST(&aobj->u_swhash[i]);
                        LIST_REMOVE(elt, list);