[ALSA] Fix possible deadlocks in sequencer at removal of ports
Fix possible rwsem deadlocks in sequencer code at removal of
sequencer ports. The list_lock of port group can be double
locked.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/core/seq/seq_ports.c b/sound/core/seq/seq_ports.c
index d881534..eefd1cf 100644
--- a/sound/core/seq/seq_ports.c
+++ b/sound/core/seq/seq_ports.c
@@ -245,9 +245,9 @@
list_del(&subs->dest_list);
else
list_del(&subs->src_list);
+ up_write(&agrp->list_mutex);
unsubscribe_port(c, aport, agrp, &subs->info, 1);
kfree(subs);
- up_write(&agrp->list_mutex);
snd_seq_port_unlock(aport);
snd_seq_client_unlock(c);
}