device property: Fix usecount for of_graph_get_port_parent()
Fix inconsistent use of of_graph_get_port_parent() where
asoc_simple_card_parse_graph_dai() does of_node_get() before
calling it while other callers do not. We can fix this by
not trashing the node passed to of_graph_get_port_parent().
Let's also make sure the callers have correct refcounts and remove
related incorrect of_node_put() calls for of_for_each_phandle
as that's done by of_phandle_iterator_next() except when
we break out of the loop early.
Let's fix both issues with a single patch to avoid kobject
refcounts getting messed up more if two patches are merged
separately.
Otherwise strange issues can happen caused by memory corruption
caused by too many kobject_del() calls such as:
BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:747
...
(___might_sleep)
(__mutex_lock)
(mutex_lock_nested)
(kernfs_remove)
(kobject_del)
(kobject_put)
(of_get_next_parent)
(of_graph_get_port_parent)
(asoc_simple_card_parse_graph_dai [snd_soc_simple_card_utils])
(asoc_graph_card_probe [snd_soc_audio_graph_card])
Fixes: 0ef472a973eb ("of_graph: add of_graph_get_port_parent()")
Fixes: 2692c1c63c29 ("ASoC: add audio-graph-card support")
Fixes: 1689333f8311 ("ASoC: simple-card-utils: add asoc_simple_card_parse_graph_dai()")
Signed-off-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Tested-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/generic/audio-graph-card.c b/sound/soc/generic/audio-graph-card.c
index 105ec3a..de2550c 100644
--- a/sound/soc/generic/audio-graph-card.c
+++ b/sound/soc/generic/audio-graph-card.c
@@ -224,9 +224,11 @@ static int asoc_graph_card_parse_of(struct graph_card_data *priv)
of_for_each_phandle(&it, rc, node, "dais", NULL, 0) {
ret = asoc_graph_card_dai_link_of(it.node, priv, idx++);
- of_node_put(it.node);
- if (ret < 0)
+ if (ret < 0) {
+ of_node_put(it.node);
+
return ret;
+ }
}
return asoc_simple_card_parse_card_name(card, NULL);
@@ -239,10 +241,8 @@ static int asoc_graph_get_dais_count(struct device *dev)
int count = 0;
int rc;
- of_for_each_phandle(&it, rc, node, "dais", NULL, 0) {
+ of_for_each_phandle(&it, rc, node, "dais", NULL, 0)
count++;
- of_node_put(it.node);
- }
return count;
}