commit 90f1831ac98b677f523fe88e0486797953f9d0ee
author Mark Salyzyn <salyzyn@google.com> Tue Mar 05 12:00:10 2019 -0800
committer Mark Salyzyn <salyzyn@google.com> Wed Mar 06 08:25:36 2019 -0800
tree 4873844062ae124a1d9ce476c5b1472758fb4e60
parent dd7313ab0d6d44e0085c18fb861552cb7104c354

fs_mgr: remount: pull root device from fstab

For devices that do not support overlayfs that are system as root,
need to pull /dev/root device from / mount point in fstab.

Test: adb-remount-test.sh
Bug: 126256072
Change-Id: I198c0e8c60770508737318afde95db2966294ff5

fs_mgr/fs_mgr_remount.cpp

diff --git a/fs_mgr/fs_mgr_remount.cpp b/fs_mgr/fs_mgr_remount.cpp
index 6312734..bb85a37 100644
--- a/fs_mgr/fs_mgr_remount.cpp
+++ b/fs_mgr/fs_mgr_remount.cpp
@@ -346,11 +346,15 @@
                 break;
             }
             if ((mount_point == "/") && (rentry.mount_point == "/system")) {
-                if (blk_device != "/dev/root") blk_device = rentry.blk_device;
+                blk_device = rentry.blk_device;
                 mount_point = "/system";
                 break;
             }
         }
+        if (blk_device == "/dev/root") {
+            auto from_fstab = GetEntryForMountPoint(&fstab, mount_point);
+            if (from_fstab) blk_device = from_fstab->blk_device;
+        }
         fs_mgr_set_blk_ro(blk_device, false);
 
         // Now remount!