Merge tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees...

[linux-2.6-block.git] / kernel / module.c

diff --git a/kernel/module.c b/kernel/module.c
index 307272679a55ae7a5122c053cdd2a3cc53bec55c..68469b37d61a0c87e6a78a53006334cdcef8b7d5 100644 (file)
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -3516,6 +3516,11 @@ static noinline int do_init_module(struct module *mod)
         * walking this with preempt disabled.  In all the failure paths, we
         * call synchronize_sched(), but we don't want to slow down the success
         * path, so use actual RCU here.
+        * Note that module_alloc() on most architectures creates W+X page
+        * mappings which won't be cleaned up until do_free_init() runs.  Any
+        * code such as mark_rodata_ro() which depends on those mappings to
+        * be cleaned up needs to sync with the queued work - ie
+        * rcu_barrier_sched()
         */
        call_rcu_sched(&freeinit->rcu, do_free_init);
        mutex_unlock(&module_mutex);