From c0a480d1acf7dc184f9f3e7cf724483b0d28dc2e Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Fri, 28 Jul 2017 01:23:15 -0700 Subject: 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 Reviewed-by: Rob Herring Tested-by: Antonio Borneo Tested-by: Kuninori Morimoto Signed-off-by: Mark Brown --- sound/soc/generic/audio-graph-scu-card.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'sound/soc/generic/audio-graph-scu-card.c') diff --git a/sound/soc/generic/audio-graph-scu-card.c b/sound/soc/generic/audio-graph-scu-card.c index dcd2df37bc3b..758ac06f3a99 100644 --- a/sound/soc/generic/audio-graph-scu-card.c +++ b/sound/soc/generic/audio-graph-scu-card.c @@ -215,7 +215,6 @@ static int asoc_graph_card_parse_of(struct graph_card_data *priv) codec_ep = of_graph_get_remote_endpoint(cpu_ep); rcpu_ep = of_graph_get_remote_endpoint(codec_ep); - of_node_put(cpu_port); of_node_put(cpu_ep); of_node_put(codec_ep); of_node_put(rcpu_ep); @@ -232,8 +231,10 @@ static int asoc_graph_card_parse_of(struct graph_card_data *priv) ret = asoc_simple_card_parse_daifmt(dev, cpu_ep, codec_ep, NULL, &daifmt); - if (ret < 0) + if (ret < 0) { + of_node_put(cpu_port); goto parse_of_err; + } } dai_idx = 0; @@ -250,7 +251,6 @@ static int asoc_graph_card_parse_of(struct graph_card_data *priv) codec_ep = of_graph_get_remote_endpoint(cpu_ep); codec_port = of_graph_get_port_parent(codec_ep); - of_node_put(cpu_port); of_node_put(cpu_ep); of_node_put(codec_ep); of_node_put(codec_port); @@ -266,13 +266,17 @@ static int asoc_graph_card_parse_of(struct graph_card_data *priv) /* Back-End (= Codec) */ ret = asoc_graph_card_dai_link_of(codec_ep, priv, daifmt, dai_idx++, 0); - if (ret < 0) + if (ret < 0) { + of_node_put(cpu_port); goto parse_of_err; + } } else { /* Front-End (= CPU) */ ret = asoc_graph_card_dai_link_of(cpu_ep, priv, daifmt, dai_idx++, 1); - if (ret < 0) + if (ret < 0) { + of_node_put(cpu_port); goto parse_of_err; + } } } } @@ -306,7 +310,6 @@ static int asoc_graph_get_dais_count(struct device *dev) codec_ep = of_graph_get_remote_endpoint(cpu_ep); codec_port = of_graph_get_port_parent(codec_ep); - of_node_put(cpu_port); of_node_put(cpu_ep); of_node_put(codec_ep); of_node_put(codec_port); -- cgit v1.2.3