updated: log git diff on overlay init (#20476)

* updated: log git diff on overlay init

* add git diff param

* params

common/params_pyx.pyx

@@ -28,6 +28,7 @@ keys = {
   b"DisableUpdates": [TxType.PERSISTENT],
   b"DoUninstall": [TxType.CLEAR_ON_MANAGER_START],
   b"DongleId": [TxType.PERSISTENT],
+  b"GitDiff": [TxType.PERSISTENT],
   b"GitBranch": [TxType.PERSISTENT],
   b"GitCommit": [TxType.PERSISTENT],
   b"GitRemote": [TxType.PERSISTENT],

selfdrive/updated.py

@@ -164,7 +164,8 @@ def init_overlay() -> None:
 
   cloudlog.info("preparing new safe staging area")
 
-  Params().put("UpdateAvailable", "0")
+  params = Params()
+  params.put("UpdateAvailable", "0")
   set_consistent_flag(False)
   dismount_overlay()
   if os.path.isdir(STAGING_ROOT):
@@ -196,6 +197,10 @@ def init_overlay() -> None:
   else:
     run(mount_cmd)
 
+  git_diff = run(["git", "diff"], OVERLAY_MERGED, low_priority=True)
+  params.put("GitDiff", git_diff)
+  cloudlog.info(f"git diff output:\n{git_diff}")
+
 
 def finalize_update() -> None:
   """Take the current OverlayFS merged view and finalize a copy outside of