The DAPM lock must be held when accessing the DAPM graph status through sysfs or debugfs, otherwise concurrent changes to the graph can result in undefined behaviour.
Signed-off-by: Lars-Peter Clausen lars@metafoo.de --- sound/soc/soc-dapm.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index a47a8ce..1779430 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -1952,6 +1952,7 @@ static ssize_t dapm_widget_power_read_file(struct file *file, size_t count, loff_t *ppos) { struct snd_soc_dapm_widget *w = file->private_data; + struct snd_soc_card *card = w->dapm->card; char *buf; int in, out; ssize_t ret; @@ -1961,6 +1962,8 @@ static ssize_t dapm_widget_power_read_file(struct file *file, if (!buf) return -ENOMEM;
+ mutex_lock(&card->dapm_mutex); + /* Supply widgets are not handled by is_connected_{input,output}_ep() */ if (w->is_supply) { in = 0; @@ -2007,6 +2010,8 @@ static ssize_t dapm_widget_power_read_file(struct file *file, p->sink->name); }
+ mutex_unlock(&card->dapm_mutex); + ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
kfree(buf); @@ -2281,11 +2286,15 @@ static ssize_t dapm_widget_show(struct device *dev, struct snd_soc_pcm_runtime *rtd = dev_get_drvdata(dev); int i, count = 0;
+ mutex_lock(&rtd->card->dapm_mutex); + for (i = 0; i < rtd->num_codecs; i++) { struct snd_soc_codec *codec = rtd->codec_dais[i]->codec; count += dapm_widget_show_codec(codec, buf + count); }
+ mutex_unlock(&rtd->card->dapm_mutex); + return count; }