3 files changed, 12 insertions, 2 deletions
diff --git a/sound/core/seq/oss/seq_oss.c b/sound/core/seq/oss/seq_oss.c
index 5f64d0d88320..e1f44fc86885 100644
--- a/sound/core/seq/oss/seq_oss.c
+++ b/sound/core/seq/oss/seq_oss.c
@@ -203,7 +203,7 @@ odev_poll(struct file *file, poll_table * wait)
 	struct seq_oss_devinfo *dp;
 	dp = file->private_data;
 	if (snd_BUG_ON(!dp))
-		return -ENXIO;
+		return EPOLLERR;
 	return snd_seq_oss_poll(dp, file, wait);
 }
 
diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 56ca78423040..6fd4b074b206 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -1101,7 +1101,7 @@ static __poll_t snd_seq_poll(struct file *file, poll_table * wait)
 
 	/* check client structures are in place */
 	if (snd_BUG_ON(!client))
-		return -ENXIO;
+		return EPOLLERR;
 
 	if ((snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT) &&
 	    client->data.user.fifo) {
diff --git a/sound/core/seq/seq_virmidi.c b/sound/core/seq/seq_virmidi.c
index 289ae6bb81d9..8ebbca554e99 100644
--- a/sound/core/seq/seq_virmidi.c
+++ b/sound/core/seq/seq_virmidi.c
@@ -163,6 +163,7 @@ static void snd_virmidi_output_trigger(struct snd_rawmidi_substream *substream,
 	int count, res;
 	unsigned char buf[32], *pbuf;
 	unsigned long flags;
+	bool check_resched = !in_atomic();
 
 	if (up) {
 		vmidi->trigger = 1;
@@ -200,6 +201,15 @@ static void snd_virmidi_output_trigger(struct snd_rawmidi_substream *substream,
 					vmidi->event.type = SNDRV_SEQ_EVENT_NONE;
 				}
 			}
+			if (!check_resched)
+				continue;
+			/* do temporary unlock & cond_resched() for avoiding
+			 * CPU soft lockup, which may happen via a write from
+			 * a huge rawmidi buffer
+			 */
+			spin_unlock_irqrestore(&substream->runtime->lock, flags);
+			cond_resched();
+			spin_lock_irqsave(&substream->runtime->lock, flags);
 		}
 	out:
 		spin_unlock_irqrestore(&substream->runtime->lock, flags);