The FILE_LOCK() implementation uses "pool mutex" under the hood, which means it should only be used as a leaf level mutex. The fdrop_locked() code wants to be called with FILE_LOCK() held, but the fdrop_locked() implementation calls mtx_lock(&Giant) before calling FILE_UNLOCK(). In addition to violating the proper usage of the "pool mutex", there is also the potential for a lock order violation. The close() implementation grabs Giant and eventually calls fdrop(), which calls FILE_LOCK() immediately before calling fdrop_locked(). If another caller of fdrop_locked() calls FILE_LOCK() without grabbing Giant first, then the lock order will be reversed when fdrop_locked() grabs Giant.
It looks like fdrop_locked() should require that Giant be grabbed by the caller before fdrop_locked() is called. _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "[EMAIL PROTECTED]"
