Hello Takashi Sakamoto,
This is a semi-automatic email about new static checker warnings.
The patch e8a40d9bcb23: "ALSA: firewire-lib: schedule work again when MIDI substream has rest of MIDI messages" from Oct 9, 2015, leads to the following Smatch complaint:
sound/firewire/lib.c:88 async_midi_port_callback() error: we previously assumed 'substream' could be null (see line 77)
sound/firewire/lib.c 76 77 if (rcode == RCODE_COMPLETE && substream != NULL) ^^^^^^^^^^^^^^^^^ Existing code assumes substream can be NULL.
78 snd_rawmidi_transmit_ack(substream, port->consume_bytes); 79 else if (!rcode_is_permanent_error(rcode)) 80 /* To start next transaction immediately for recovery. */ 81 port->next_ktime = ktime_set(0, 0); 82 else 83 /* Don't continue processing. */ 84 port->error = true; 85 86 port->idling = true; 87 88 if (!snd_rawmidi_transmit_empty(substream)) ^^^^^^^^^ Patch adds an unchecked dereference (inside the function call).
89 schedule_work(&port->work); 90 }
regards, dan carpenter