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Diffstat (limited to 'kernel/jump_label.c')
-rw-r--r--kernel/jump_label.c77
1 files changed, 66 insertions, 11 deletions
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index 7be868bf25c6..3b79bd938330 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -39,6 +39,16 @@ struct jump_label_module_entry {
struct module *mod;
};
+void jump_label_lock(void)
+{
+ mutex_lock(&jump_label_mutex);
+}
+
+void jump_label_unlock(void)
+{
+ mutex_unlock(&jump_label_mutex);
+}
+
static int jump_label_cmp(const void *a, const void *b)
{
const struct jump_entry *jea = a;
@@ -152,7 +162,7 @@ void jump_label_update(unsigned long key, enum jump_label_type type)
struct jump_label_module_entry *e_module;
int count;
- mutex_lock(&jump_label_mutex);
+ jump_label_lock();
entry = get_jump_label_entry((jump_label_t)key);
if (entry) {
count = entry->nr_entries;
@@ -168,13 +178,14 @@ void jump_label_update(unsigned long key, enum jump_label_type type)
count = e_module->nr_entries;
iter = e_module->table;
while (count--) {
- if (kernel_text_address(iter->code))
+ if (iter->key &&
+ kernel_text_address(iter->code))
arch_jump_label_transform(iter, type);
iter++;
}
}
}
- mutex_unlock(&jump_label_mutex);
+ jump_label_unlock();
}
static int addr_conflict(struct jump_entry *entry, void *start, void *end)
@@ -231,6 +242,7 @@ out:
* overlaps with any of the jump label patch addresses. Code
* that wants to modify kernel text should first verify that
* it does not overlap with any of the jump label addresses.
+ * Caller must hold jump_label_mutex.
*
* returns 1 if there is an overlap, 0 otherwise
*/
@@ -241,7 +253,6 @@ int jump_label_text_reserved(void *start, void *end)
struct jump_entry *iter_stop = __start___jump_table;
int conflict = 0;
- mutex_lock(&jump_label_mutex);
iter = iter_start;
while (iter < iter_stop) {
if (addr_conflict(iter, start, end)) {
@@ -256,10 +267,16 @@ int jump_label_text_reserved(void *start, void *end)
conflict = module_conflict(start, end);
#endif
out:
- mutex_unlock(&jump_label_mutex);
return conflict;
}
+/*
+ * Not all archs need this.
+ */
+void __weak arch_jump_label_text_poke_early(jump_label_t addr)
+{
+}
+
static __init int init_jump_label(void)
{
int ret;
@@ -267,7 +284,7 @@ static __init int init_jump_label(void)
struct jump_entry *iter_stop = __stop___jump_table;
struct jump_entry *iter;
- mutex_lock(&jump_label_mutex);
+ jump_label_lock();
ret = build_jump_label_hashtable(__start___jump_table,
__stop___jump_table);
iter = iter_start;
@@ -275,7 +292,7 @@ static __init int init_jump_label(void)
arch_jump_label_text_poke_early(iter->code);
iter++;
}
- mutex_unlock(&jump_label_mutex);
+ jump_label_unlock();
return ret;
}
early_initcall(init_jump_label);
@@ -366,6 +383,39 @@ static void remove_jump_label_module(struct module *mod)
}
}
+static void remove_jump_label_module_init(struct module *mod)
+{
+ struct hlist_head *head;
+ struct hlist_node *node, *node_next, *module_node, *module_node_next;
+ struct jump_label_entry *e;
+ struct jump_label_module_entry *e_module;
+ struct jump_entry *iter;
+ int i, count;
+
+ /* if the module doesn't have jump label entries, just return */
+ if (!mod->num_jump_entries)
+ return;
+
+ for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
+ head = &jump_label_table[i];
+ hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
+ hlist_for_each_entry_safe(e_module, module_node,
+ module_node_next,
+ &(e->modules), hlist) {
+ if (e_module->mod != mod)
+ continue;
+ count = e_module->nr_entries;
+ iter = e_module->table;
+ while (count--) {
+ if (within_module_init(iter->code, mod))
+ iter->key = 0;
+ iter++;
+ }
+ }
+ }
+ }
+}
+
static int
jump_label_module_notify(struct notifier_block *self, unsigned long val,
void *data)
@@ -375,16 +425,21 @@ jump_label_module_notify(struct notifier_block *self, unsigned long val,
switch (val) {
case MODULE_STATE_COMING:
- mutex_lock(&jump_label_mutex);
+ jump_label_lock();
ret = add_jump_label_module(mod);
if (ret)
remove_jump_label_module(mod);
- mutex_unlock(&jump_label_mutex);
+ jump_label_unlock();
break;
case MODULE_STATE_GOING:
- mutex_lock(&jump_label_mutex);
+ jump_label_lock();
remove_jump_label_module(mod);
- mutex_unlock(&jump_label_mutex);
+ jump_label_unlock();
+ break;
+ case MODULE_STATE_LIVE:
+ jump_label_lock();
+ remove_jump_label_module_init(mod);
+ jump_label_unlock();
break;
}
return ret;

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