Changeset 6f9a9bc in mainline

Timestamp:

2006-06-06T01:04:01Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

874621f

Parents:

c74804f

Message:

Never ever walk a B+tree as you destroy it. Or vice versa.

File:

• generic/src/mm/as.c (modified) (3 diffs)

generic/src/mm/as.c

@@ -137 +137 @@
 {
         ipl_t ipl;
-        link_t *cur;
+        bool cond;
 
         ASSERT(as->refcount == 0);
@@ -145 +145 @@
          * it is safe not to lock its mutex.
          */
-         
         ipl = interrupts_disable();
         spinlock_lock(&inactive_as_with_asid_lock);
-
         if (as->asid != ASID_INVALID && as != AS_KERNEL) {
-                if (!as->cpu_refcount)
+                if (as != AS && as->cpu_refcount == 0)
                         list_remove(&as->inactive_as_with_asid_link);
                 asid_put(as->asid);
@@ -158 +156 @@
         /*
          * Destroy address space areas of the address space.
+         * The B+tee must be walked carefully because it is
+         * also being destroyed.
          */     
-        for (cur = as->as_area_btree.leaf_head.next; cur != &as->as_area_btree.leaf_head; cur = cur->next) {
+        for (cond = true; cond; ) {
                 btree_node_t *node;
-                int i;
-                
-                node = list_get_instance(cur, btree_node_t, leaf_link);
-                for (i = 0; i < node->keys; i++)
-                        as_area_destroy(as, node->key[i]);
+
+                ASSERT(!list_empty(&as->as_area_btree.leaf_head));
+                node = list_get_instance(as->as_area_btree.leaf_head.next, btree_node_t, leaf_link);
+
+                if ((cond = node->keys)) {
+                        as_area_destroy(as, node->key[0]);
+                }
         }