在 compact.c 中添加对 copy_to_user 函数的外部声明，并调整编译选项以优化性能

kernel/kpm/compact.c

@@ -42,6 +42,15 @@ __visible __section(".data") static struct CompactAddressSymbol address_symbol [
     { "is_run_in_sukisu_ultra", (void*)1 }
 };
 
+#pragma GCC push_options
+#pragma GCC optimize ("flto")
+#pragma GCC visibility push(default)
+
+extern long copy_to_user(void __user *to, const void *from, unsigned long n);
+
+#pragma GCC visibility pop
+#pragma GCC pop_options
+
 __visible __section(".text") unsigned long sukisu_compact_find_symbol(const char* name) {
     int i;
     unsigned long addr;