Merge "libutils: clearer abort on overflow." into tm-dev
diff --git a/init/bootchart.cpp b/init/bootchart.cpp
index b7db9b6..f46fb09 100644
--- a/init/bootchart.cpp
+++ b/init/bootchart.cpp
@@ -140,6 +140,20 @@
 static void bootchart_thread_main() {
   LOG(INFO) << "Bootcharting started";
 
+  // Unshare the mount namespace of this thread so that the init process itself can switch
+  // the mount namespace later while this thread is still running.
+  // Otherwise, setns() call invoked as part of `enter_default_mount_ns` fails with EINVAL.
+  //
+  // Note that after unshare()'ing the mount namespace from the main thread, this thread won't
+  // receive mount/unmount events from the other mount namespace unless the events are happening
+  // from under a sharable mount.
+  //
+  // The bootchart thread is safe to unshare the mount namespace because it only reads from /proc
+  // and write to /data which are not private mounts.
+  if (unshare(CLONE_NEWNS) == -1) {
+      PLOG(ERROR) << "Cannot create mount namespace";
+      return;
+  }
   // Open log files.
   auto stat_log = fopen_unique("/data/bootchart/proc_stat.log", "we");
   if (!stat_log) return;