firmware: log exceptions in debug mode (no silent unhandled exceptions)

src/apps/fido_u2f/__init__.py

@@ -416,8 +416,10 @@ class ConfirmContent(ui.Widget):
             try:
                 namepart = name.lower().replace(" ", "_")
                 icon = res.load("apps/fido_u2f/res/u2f_%s.toif" % namepart)
-            except Exception:
+            except Exception as e:
                 icon = res.load("apps/fido_u2f/res/u2f_generic.toif")
+                if __debug__:
+                    log.exception(__name__, e)
         else:
             name = "%s...%s" % (
                 hexlify(self.app_id[:4]).decode(),

src/boot.py

@@ -1,4 +1,4 @@
-from trezor import config, loop, res, ui
+from trezor import config, log, loop, res, ui
 from trezor.pin import pin_to_int, show_pin_timeout
 
 from apps.common.request_pin import request_pin
@@ -18,8 +18,9 @@ async def bootscreen():
                     return
                 else:
                     label = "Wrong PIN, enter again"
-        except:  # noqa: E722
-            pass
+        except Exception as e:
+            if __debug__:
+                log.exception(__name__, e)
 
 
 async def lockscreen():

src/trezor/loop.py

@@ -261,6 +261,8 @@ class spawn(Syscall):
             result = await child
         except Exception as e:
             self._finish(child, index, e)
+            if __debug__:
+                log.exception(__name__, e)
         else:
             self._finish(child, index, result)
 

src/trezor/messages/__init__.py

@@ -29,4 +29,8 @@ def get_type(wire_type):
 
 # build reverse table of wire types
 for msg_name in dir(MessageType):
+    # Modules contain internal variables that may cause exception here.
+    # No Message begins with underscore so it's safe to skip those.
+    if (msg_name[0] == '_'):
+        continue
     type_to_name[getattr(MessageType, msg_name)] = msg_name