The patch
device property: Fix usecount for of_graph_get_port_parent()
has been applied to the asoc tree at
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git
All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying to this mail.
Thanks, Mark
From c0a480d1acf7dc184f9f3e7cf724483b0d28dc2e Mon Sep 17 00:00:00 2001
From: Tony Lindgren tony@atomide.com Date: Fri, 28 Jul 2017 01:23:15 -0700 Subject: [PATCH] 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 --- drivers/of/property.c | 17 +++++++++++++++-- sound/soc/generic/audio-graph-card.c | 10 +++++----- sound/soc/generic/audio-graph-scu-card.c | 15 +++++++++------ sound/soc/generic/simple-card-utils.c | 8 +++----- sound/soc/soc-core.c | 2 ++ 5 files changed, 34 insertions(+), 18 deletions(-)
diff --git a/drivers/of/property.c b/drivers/of/property.c index eda50b4be934..067f9fab7b77 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c @@ -708,6 +708,15 @@ struct device_node *of_graph_get_port_parent(struct device_node *node) { unsigned int depth;
+ if (!node) + return NULL; + + /* + * Preserve usecount for passed in node as of_get_next_parent() + * will do of_node_put() on it. + */ + of_node_get(node); + /* Walk 3 levels up only if there is 'ports' node. */ for (depth = 3; depth && node; depth--) { node = of_get_next_parent(node); @@ -728,12 +737,16 @@ EXPORT_SYMBOL(of_graph_get_port_parent); struct device_node *of_graph_get_remote_port_parent( const struct device_node *node) { - struct device_node *np; + struct device_node *np, *pp;
/* Get remote endpoint node. */ np = of_graph_get_remote_endpoint(node);
- return of_graph_get_port_parent(np); + pp = of_graph_get_port_parent(np); + + of_node_put(np); + + return pp; } EXPORT_SYMBOL(of_graph_get_remote_port_parent);
diff --git a/sound/soc/generic/audio-graph-card.c b/sound/soc/generic/audio-graph-card.c index 105ec3a6e30d..de2550c7a96b 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; } 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); diff --git a/sound/soc/generic/simple-card-utils.c b/sound/soc/generic/simple-card-utils.c index 26d64fa40c9c..7d7ab4aee42e 100644 --- a/sound/soc/generic/simple-card-utils.c +++ b/sound/soc/generic/simple-card-utils.c @@ -263,6 +263,9 @@ static int asoc_simple_card_get_dai_id(struct device_node *ep) id = i; i++; } + + of_node_put(node); + if (id < 0) return -ENODEV;
@@ -282,11 +285,6 @@ int asoc_simple_card_parse_graph_dai(struct device_node *ep, if (!dai_name) return 0;
- /* - * of_graph_get_port_parent() will call - * of_node_put(). So, call of_node_get() here - */ - of_node_get(ep); node = of_graph_get_port_parent(ep);
/* Get dai->name */ diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index 921622a01944..0cf8498fa36c 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -4113,6 +4113,8 @@ int snd_soc_get_dai_id(struct device_node *ep) } mutex_unlock(&client_mutex);
+ of_node_put(node); + return ret; } EXPORT_SYMBOL_GPL(snd_soc_get_dai_id);