[ActivityManager] Prevent application holding AMS lock
Symptom:
Watchdog timeout.
Reproduce code:
String action = "lets.deadlock";
Uri baseUri = Uri.parse("content://i.am.bad");
Uri uri = ContentUris.withAppendedId(baseUri, 1);
Intent intent = new Intent(action, uri);
sendStickyBroadcast(intent);
IntentFilter filter = new IntentFilter(action);
filter.addDataScheme(baseUri.getScheme());
filter.addDataAuthority(baseUri.getAuthority(), null);
filter.addDataPath(uri.getPath(), 0);
registerReceiver(null, filter);
In target provider's getType:
Invoke AMS function will result deadlock.
Or sleep a long time will also trigger watchdog timeout.
Root Cause:
If broadcast is sticky with content scheme intent.
Register receiver will trigger access provider when
matching intent with IntentFilter, and it executes
in ActivityManagerService's lock.
Solution:
Obtain necessary data to local to split lock block.
Change-Id: I0fb94472cdc478997e40ba2a60a988c5f53badb2
1 file changed