diff --git a/Android.mk b/Android.mk
index 96af417..4a730b5 100644
--- a/Android.mk
+++ b/Android.mk
@@ -45,8 +45,8 @@
     $(TARGET_RECOVERY_UI_LIB)
 
 LOCAL_SHARED_LIBRARIES := \
-    libbase \
-    liblog \
+    libbase.recovery \
+    liblog.recovery \
     librecovery_ui.recovery
 
 include $(BUILD_SHARED_LIBRARY)
diff --git a/OWNERS b/OWNERS
index 79dd9f7..45c72e3 100644
--- a/OWNERS
+++ b/OWNERS
@@ -1,5 +1,4 @@
 elsk@google.com
-enh@google.com
 nhdo@google.com
 xunchang@google.com
-zhaojiac@google.com
+zhangkelvin@google.com
diff --git a/PREUPLOAD.cfg b/PREUPLOAD.cfg
index 28aa06f..023d48b 100644
--- a/PREUPLOAD.cfg
+++ b/PREUPLOAD.cfg
@@ -6,5 +6,6 @@
 clang_format = --commit ${PREUPLOAD_COMMIT} --style file --extensions c,h,cc,cpp
 
 [Hook Scripts]
+aosp_hook = ${REPO_ROOT}/frameworks/base/tools/aosp/aosp_sha.sh ${PREUPLOAD_COMMIT} "."
 checkstyle_hook = ${REPO_ROOT}/prebuilts/checkstyle/checkstyle.py --sha ${PREUPLOAD_COMMIT}
                   --file_whitelist tools/ updater_sample/
diff --git a/minui/graphics.cpp b/minui/graphics.cpp
index dce1e61..f25694a 100644
--- a/minui/graphics.cpp
+++ b/minui/graphics.cpp
@@ -42,6 +42,9 @@
 static GRSurface* gr_draw = nullptr;
 static GRRotation rotation = GRRotation::NONE;
 static PixelFormat pixel_format = PixelFormat::UNKNOWN;
+// The graphics backend list that provides fallback options for the default backend selection.
+// For example, it will fist try DRM, then try FBDEV if DRM is unavailable.
+constexpr auto default_backends = { GraphicsBackend::DRM, GraphicsBackend::FBDEV };
 
 static bool outside(int x, int y) {
   auto swapped = (rotation == GRRotation::LEFT || rotation == GRRotation::RIGHT);
@@ -340,7 +343,22 @@
   gr_draw = gr_backend->Flip();
 }
 
+std::unique_ptr<MinuiBackend> create_backend(GraphicsBackend backend) {
+  switch (backend) {
+    case GraphicsBackend::DRM:
+      return std::make_unique<MinuiBackendDrm>();
+    case GraphicsBackend::FBDEV:
+      return std::make_unique<MinuiBackendFbdev>();
+    default:
+      return nullptr;
+  }
+}
+
 int gr_init() {
+  return gr_init(default_backends);
+}
+
+int gr_init(std::initializer_list<GraphicsBackend> backends) {
   // pixel_format needs to be set before loading any resources or initializing backends.
   std::string format = android::base::GetProperty("ro.minui.pixel_format", "");
   if (format == "ABGR_8888") {
@@ -361,19 +379,22 @@
            ret);
   }
 
-  auto backend = std::unique_ptr<MinuiBackend>{ std::make_unique<MinuiBackendDrm>() };
-  gr_draw = backend->Init();
-
-  if (!gr_draw) {
-    backend = std::make_unique<MinuiBackendFbdev>();
-    gr_draw = backend->Init();
+  std::unique_ptr<MinuiBackend> minui_backend;
+  for (GraphicsBackend backend : backends) {
+    minui_backend = create_backend(backend);
+    if (!minui_backend) {
+      printf("gr_init: minui_backend %d is a nullptr\n", backend);
+      continue;
+    }
+    gr_draw = minui_backend->Init();
+    if (gr_draw) break;
   }
 
   if (!gr_draw) {
     return -1;
   }
 
-  gr_backend = backend.release();
+  gr_backend = minui_backend.release();
 
   int overscan_percent = android::base::GetIntProperty("ro.minui.overscan_percent", 0);
   overscan_offset_x = gr_draw->width * overscan_percent / 100;
diff --git a/minui/graphics_drm.cpp b/minui/graphics_drm.cpp
index 95759e3..9d31ff7 100644
--- a/minui/graphics_drm.cpp
+++ b/minui/graphics_drm.cpp
@@ -105,6 +105,8 @@
     perror("Failed to DRM_IOCTL_MODE_CREATE_DUMB");
     return nullptr;
   }
+  printf("Allocating buffer with resolution %d x %d pitch: %d bpp: %d, size: %llu\n", width, height,
+         create_dumb.pitch, create_dumb.bpp, create_dumb.size);
 
   // Cannot use std::make_unique to access non-public ctor.
   auto surface = std::unique_ptr<GRSurfaceDrm>(new GRSurfaceDrm(
@@ -128,13 +130,14 @@
     return nullptr;
   }
 
-  auto mmapped = mmap(nullptr, surface->height * surface->row_bytes, PROT_READ | PROT_WRITE,
-                      MAP_SHARED, drm_fd, map_dumb.offset);
+  auto mmapped =
+      mmap(nullptr, create_dumb.size, PROT_READ | PROT_WRITE, MAP_SHARED, drm_fd, map_dumb.offset);
   if (mmapped == MAP_FAILED) {
     perror("Failed to mmap()");
     return nullptr;
   }
   surface->mmapped_buffer_ = static_cast<uint8_t*>(mmapped);
+  printf("Framebuffer of size %llu allocated @ %p\n", create_dumb.size, surface->mmapped_buffer_);
   return surface;
 }
 
@@ -260,9 +263,16 @@
   /* If we still didn't find a connector, give up and return. */
   if (!main_monitor_connector) return nullptr;
 
+  for (int modes = 0; modes < main_monitor_connector->count_modes; modes++) {
+    printf("Display Mode %d resolution: %d x %d @ %d FPS\n", modes,
+           main_monitor_connector->modes[modes].hdisplay,
+           main_monitor_connector->modes[modes].vdisplay,
+           main_monitor_connector->modes[modes].vrefresh);
+  }
   *mode_index = 0;
   for (int modes = 0; modes < main_monitor_connector->count_modes; modes++) {
     if (main_monitor_connector->modes[modes].type & DRM_MODE_TYPE_PREFERRED) {
+      printf("Choosing display mode #%d\n", modes);
       *mode_index = modes;
       break;
     }
diff --git a/minui/graphics_fbdev.cpp b/minui/graphics_fbdev.cpp
index 2584017..0d0fabc 100644
--- a/minui/graphics_fbdev.cpp
+++ b/minui/graphics_fbdev.cpp
@@ -131,8 +131,6 @@
   SetDisplayedFramebuffer(0);
 
   printf("framebuffer: %d (%zu x %zu)\n", fb_fd.get(), gr_draw->width, gr_draw->height);
-
-  Blank(true);
   Blank(false);
 
   return gr_draw;
diff --git a/minui/include/minui/minui.h b/minui/include/minui/minui.h
index 163e41d..5470457 100644
--- a/minui/include/minui/minui.h
+++ b/minui/include/minui/minui.h
@@ -104,10 +104,19 @@
   ARGB = 4,
 };
 
-// Initializes the graphics backend and loads font file. Returns 0 on success, or -1 on error. Note
-// that the font initialization failure would be non-fatal, as caller may not need to draw any text
-// at all. Caller can check the font initialization result via gr_sys_font() as needed.
+enum class GraphicsBackend : int {
+  UNKNOWN = 0,
+  DRM = 1,
+  FBDEV = 2,
+};
+
+// Initializes the default graphics backend and loads font file. Returns 0 on success, or -1 on
+// error. Note that the font initialization failure would be non-fatal, as caller may not need to
+// draw any text at all. Caller can check the font initialization result via gr_sys_font() as
+// needed.
 int gr_init();
+// Supports backend selection for minui client.
+int gr_init(std::initializer_list<GraphicsBackend> backends);
 
 // Frees the allocated resources. The function is idempotent, and safe to be called if gr_init()
 // didn't finish successfully.
diff --git a/update_verifier/Android.bp b/update_verifier/Android.bp
index ff2eff9..220b007 100644
--- a/update_verifier/Android.bp
+++ b/update_verifier/Android.bp
@@ -33,6 +33,25 @@
     ],
 }
 
+python_library_host {
+    name: "care_map_proto_py",
+    srcs: [
+        "care_map.proto",
+    ],
+    proto: {type: "lite", canonical_path_from_root: false},
+    version: {
+        py2: {
+            enabled: true,
+        },
+        py3: {
+            enabled: true,
+        },
+    },
+    visibility: [
+        "//build/make/tools/releasetools:__subpackages__",
+    ],
+}
+
 cc_library_static {
     name: "libupdate_verifier",