[PATCH] ASoC: simple-card: Fix refcount underflow

[PATCH] ASoC: simple-card: Fix refcount underflow

[Daniel Baluta]

of_get_child_by_name() takes a reference we'll need to drop
later so when we substitute in top we need to take a reference
as well as just assigning.

Without this patch we hit the following error:

[    1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
[    1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
[    1.266807] Workqueue: events deferred_probe_work_func
[    1.271950] Call trace:
[    1.274406]  dump_backtrace+0x0/0x158
[    1.278074]  show_stack+0x14/0x20
[    1.281396]  dump_stack+0xa8/0xcc
[    1.284717]  of_node_release+0xb0/0xc8
[    1.288474]  kobject_put+0x74/0xf0
[    1.291879]  of_node_put+0x14/0x28
[    1.295286]  __of_get_next_child+0x44/0x70
[    1.299387]  of_get_next_child+0x3c/0x60
[    1.303315]  simple_for_each_link+0x1dc/0x230
[    1.307676]  simple_probe+0x80/0x540
[    1.311256]  platform_drv_probe+0x50/0xa0

This patch is based on an earlier version posted by Kuninori Morimoto
and commit message includes explanations from Mark Brown.

https://patchwork.kernel.org/patch/10814255/

Reported-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
---
 sound/soc/generic/simple-card.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c
index 08df261024cf..dc18c4492955 100644
--- a/sound/soc/generic/simple-card.c
+++ b/sound/soc/generic/simple-card.c
@@ -445,7 +445,7 @@ static int simple_for_each_link(struct simple_priv *priv,
 	/* Check if it has dai-link */
 	node = of_get_child_by_name(top, PREFIX "dai-link");
 	if (!node) {
-		node = top;
+		node = of_node_get(top);
 		is_top = 1;
 	}
 
-- 
2.17.1

Re: [PATCH] ASoC: simple-card: Fix refcount underflow

[Kuninori Morimoto]

Hi Daniel, Mark

> of_get_child_by_name() takes a reference we'll need to drop
> later so when we substitute in top we need to take a reference
> as well as just assigning.
> 
> Without this patch we hit the following error:
> 
> [    1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
> [    1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
> [    1.266807] Workqueue: events deferred_probe_work_func
> [    1.271950] Call trace:
> [    1.274406]  dump_backtrace+0x0/0x158
> [    1.278074]  show_stack+0x14/0x20
> [    1.281396]  dump_stack+0xa8/0xcc
> [    1.284717]  of_node_release+0xb0/0xc8
> [    1.288474]  kobject_put+0x74/0xf0
> [    1.291879]  of_node_put+0x14/0x28
> [    1.295286]  __of_get_next_child+0x44/0x70
> [    1.299387]  of_get_next_child+0x3c/0x60
> [    1.303315]  simple_for_each_link+0x1dc/0x230
> [    1.307676]  simple_probe+0x80/0x540
> [    1.311256]  platform_drv_probe+0x50/0xa0
> 
> This patch is based on an earlier version posted by Kuninori Morimoto
> and commit message includes explanations from Mark Brown.
> 
> https://patchwork.kernel.org/patch/10814255/
> 
> Reported-by: Vicente Bergas <vicencb@gmail.com>
> Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
> ---

I'm not sure which one is correct in this case

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

or

Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

>  sound/soc/generic/simple-card.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c
> index 08df261024cf..dc18c4492955 100644
> --- a/sound/soc/generic/simple-card.c
> +++ b/sound/soc/generic/simple-card.c
> @@ -445,7 +445,7 @@ static int simple_for_each_link(struct simple_priv *priv,
>  	/* Check if it has dai-link */
>  	node = of_get_child_by_name(top, PREFIX "dai-link");
>  	if (!node) {
> -		node = top;
> +		node = of_node_get(top);
>  		is_top = 1;
>  	}
>  
> -- 
> 2.17.1
> 

Re: [PATCH] ASoC: simple-card: Fix refcount underflow

[Kuninori Morimoto]

Hi Daniel, Mark, again

> > of_get_child_by_name() takes a reference we'll need to drop
> > later so when we substitute in top we need to take a reference
> > as well as just assigning.
> > 
> > Without this patch we hit the following error:
> > 
> > [    1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
> > [    1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
> > [    1.266807] Workqueue: events deferred_probe_work_func
> > [    1.271950] Call trace:
> > [    1.274406]  dump_backtrace+0x0/0x158
> > [    1.278074]  show_stack+0x14/0x20
> > [    1.281396]  dump_stack+0xa8/0xcc
> > [    1.284717]  of_node_release+0xb0/0xc8
> > [    1.288474]  kobject_put+0x74/0xf0
> > [    1.291879]  of_node_put+0x14/0x28
> > [    1.295286]  __of_get_next_child+0x44/0x70
> > [    1.299387]  of_get_next_child+0x3c/0x60
> > [    1.303315]  simple_for_each_link+0x1dc/0x230
> > [    1.307676]  simple_probe+0x80/0x540
> > [    1.311256]  platform_drv_probe+0x50/0xa0
> > 
> > This patch is based on an earlier version posted by Kuninori Morimoto
> > and commit message includes explanations from Mark Brown.
> > 
> > https://patchwork.kernel.org/patch/10814255/
> > 
> > Reported-by: Vicente Bergas <vicencb@gmail.com>
> > Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
> > ---
> 
> I'm not sure which one is correct in this case
> 
> Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> 
> or
> 
> Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

And we want to add

Fixes: commit da215354eb55c ("ASoC: simple-card: merge simple-scu-card")

Re: [PATCH] ASoC: simple-card: Fix refcount underflow

[Daniel Baluta]

On Mon, 2019-02-18 at 10:37 +0900, Kuninori Morimoto wrote:
> Hi Daniel, Mark, again
> 
> > > of_get_child_by_name() takes a reference we'll need to drop
> > > later so when we substitute in top we need to take a reference
> > > as well as just assigning.
> > > 
> > > Without this patch we hit the following error:
> > > 
> > > [    1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
> > > [    1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
> > > [    1.266807] Workqueue: events deferred_probe_work_func
> > > [    1.271950] Call trace:
> > > [    1.274406]  dump_backtrace+0x0/0x158
> > > [    1.278074]  show_stack+0x14/0x20
> > > [    1.281396]  dump_stack+0xa8/0xcc
> > > [    1.284717]  of_node_release+0xb0/0xc8
> > > [    1.288474]  kobject_put+0x74/0xf0
> > > [    1.291879]  of_node_put+0x14/0x28
> > > [    1.295286]  __of_get_next_child+0x44/0x70
> > > [    1.299387]  of_get_next_child+0x3c/0x60
> > > [    1.303315]  simple_for_each_link+0x1dc/0x230
> > > [    1.307676]  simple_probe+0x80/0x540
> > > [    1.311256]  platform_drv_probe+0x50/0xa0
> > > 
> > > This patch is based on an earlier version posted by Kuninori
> > > Morimoto
> > > and commit message includes explanations from Mark Brown.
> > > 
> > > 
https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.kernel.org%2Fpatch%2F10814255%2F&data=02%7C01%7Cdaniel.baluta%40nxp.com%7Ced1b7adc66a546c1bb4608d69541aaf8%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C636860506617983174&sdata=hTsurDLdtLAtTw0a5v%2FrSsleSawAP2yiVPl87%2BHCzTI%3D&reserved=0
> > > 
> > > Reported-by: Vicente Bergas <vicencb@gmail.com>
> > > Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
> > > ---
> > 
> > I'm not sure which one is correct in this case
> > 
> > Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> > 
> > or
> > 
> > Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> 
> And we want to add
> 
> Fixes: commit da215354eb55c ("ASoC: simple-card: merge simple-scu-
> card")
> 

Thanks! I thought about adding this but the current patch will not
cleanly apply because of:

2d01a84605a55c ("ASoC: simple-card: reduce naming prefix")

Re: [PATCH] ASoC: simple-card: Fix refcount underflow

[Takashi Iwai]

On Mon, 18 Feb 2019 08:06:19 +0100,
Daniel Baluta wrote:
> 
> On Mon, 2019-02-18 at 10:37 +0900, Kuninori Morimoto wrote:
> > Hi Daniel, Mark, again
> > 
> > > > of_get_child_by_name() takes a reference we'll need to drop
> > > > later so when we substitute in top we need to take a reference
> > > > as well as just assigning.
> > > > 
> > > > Without this patch we hit the following error:
> > > > 
> > > > [    1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
> > > > [    1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
> > > > [    1.266807] Workqueue: events deferred_probe_work_func
> > > > [    1.271950] Call trace:
> > > > [    1.274406]  dump_backtrace+0x0/0x158
> > > > [    1.278074]  show_stack+0x14/0x20
> > > > [    1.281396]  dump_stack+0xa8/0xcc
> > > > [    1.284717]  of_node_release+0xb0/0xc8
> > > > [    1.288474]  kobject_put+0x74/0xf0
> > > > [    1.291879]  of_node_put+0x14/0x28
> > > > [    1.295286]  __of_get_next_child+0x44/0x70
> > > > [    1.299387]  of_get_next_child+0x3c/0x60
> > > > [    1.303315]  simple_for_each_link+0x1dc/0x230
> > > > [    1.307676]  simple_probe+0x80/0x540
> > > > [    1.311256]  platform_drv_probe+0x50/0xa0
> > > > 
> > > > This patch is based on an earlier version posted by Kuninori
> > > > Morimoto
> > > > and commit message includes explanations from Mark Brown.
> > > > 
> > > > 
> https://emea01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.kernel.org%2Fpatch%2F10814255%2F&data=02%7C01%7Cdaniel.baluta%40nxp.com%7Ced1b7adc66a546c1bb4608d69541aaf8%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C636860506617983174&sdata=hTsurDLdtLAtTw0a5v%2FrSsleSawAP2yiVPl87%2BHCzTI%3D&reserved=0
> > > > 
> > > > Reported-by: Vicente Bergas <vicencb@gmail.com>
> > > > Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
> > > > ---
> > > 
> > > I'm not sure which one is correct in this case
> > > 
> > > Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> > > 
> > > or
> > > 
> > > Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> > 
> > And we want to add
> > 
> > Fixes: commit da215354eb55c ("ASoC: simple-card: merge simple-scu-
> > card")
> > 
> 
> Thanks! I thought about adding this but the current patch will not
> cleanly apply because of:
> 
> 2d01a84605a55c ("ASoC: simple-card: reduce naming prefix")

Yeah, it's a bit tricky because of the code change at this time.

At best, send two patches, once for 5.0 and once for 5.1, and let Mark
apply both of them and do the empty merge from 5.0 to 5.1, or let him
resolve the merge conflict by applying manually the 5.1 patch.


thanks,

Takashi

Re: [PATCH] ASoC: simple-card: Fix refcount underflow

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 970 bytes --]

On Mon, Feb 18, 2019 at 08:52:26AM +0100, Takashi Iwai wrote:
> Daniel Baluta wrote:

> > > Fixes: commit da215354eb55c ("ASoC: simple-card: merge simple-scu-
> > > card")

> > Thanks! I thought about adding this but the current patch will not
> > cleanly apply because of:

> > 2d01a84605a55c ("ASoC: simple-card: reduce naming prefix")

That doesn't matter for fixes tags.  However...

> Yeah, it's a bit tricky because of the code change at this time.

> At best, send two patches, once for 5.0 and once for 5.1, and let Mark
> apply both of them and do the empty merge from 5.0 to 5.1, or let him
> resolve the merge conflict by applying manually the 5.1 patch.

...since this is something that needs to be fixed for v5.0 we need a
patch that can be applied on v5.0 (and has been tested by someone who
sees the issue there).  Takashi's plan seems like a good way to do that,
if you could send a patch against my for-5.0 branch (or just Linus'
tree) that'd be great.

[-- Attachment #2: signature.asc --]
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Re: [alsa-devel] [PATCH] ASoC: simple-card: Fix refcount underflow

[Daniel Baluta]

On Mon, Feb 18, 2019 at 7:50 PM Mark Brown <broonie@kernel.org> wrote:
>
> On Mon, Feb 18, 2019 at 08:52:26AM +0100, Takashi Iwai wrote:
> > Daniel Baluta wrote:
>
> > > > Fixes: commit da215354eb55c ("ASoC: simple-card: merge simple-scu-
> > > > card")
>
> > > Thanks! I thought about adding this but the current patch will not
> > > cleanly apply because of:
>
> > > 2d01a84605a55c ("ASoC: simple-card: reduce naming prefix")
>
> That doesn't matter for fixes tags.  However...
>
> > Yeah, it's a bit tricky because of the code change at this time.
>
> > At best, send two patches, once for 5.0 and once for 5.1, and let Mark
> > apply both of them and do the empty merge from 5.0 to 5.1, or let him
> > resolve the merge conflict by applying manually the 5.1 patch.
>
> ...since this is something that needs to be fixed for v5.0 we need a
> patch that can be applied on v5.0 (and has been tested by someone who
> sees the issue there).  Takashi's plan seems like a good way to do that,
> if you could send a patch against my for-5.0 branch (or just Linus'
> tree) that'd be great.

for-5.0 branch Kuninori's patch works fine:

https://patchwork.kernel.org/patch/10814255/

for-5.1 branch and later my patch works fine:

https://patchwork.kernel.org/patch/10817449/

Would you want me to change the patch for 5.0 to have an identical commit
message as the one for 5.1?

Re: [alsa-devel] [PATCH] ASoC: simple-card: Fix refcount underflow

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 252 bytes --]

On Mon, Feb 18, 2019 at 08:00:48PM +0200, Daniel Baluta wrote:

> Would you want me to change the patch for 5.0 to have an identical commit
> message as the one for 5.1?

No, that's fine - since Morimoto-san's patch has been tested I'll just use
that.

[-- Attachment #2: signature.asc --]
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Applied "ASoC: simple-card: Fix refcount underflow" to the asoc tree

[Mark Brown]

The patch

   ASoC: simple-card: Fix refcount underflow

has been applied to the asoc tree at

   https://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 461d854c0dba3cdf63cce37ffb9423eca0793a47 Mon Sep 17 00:00:00 2001
From: Daniel Baluta <daniel.baluta@nxp.com>
Date: Sat, 16 Feb 2019 10:09:42 +0000
Subject: [PATCH] ASoC: simple-card: Fix refcount underflow

of_get_child_by_name() takes a reference we'll need to drop
later so when we substitute in top we need to take a reference
as well as just assigning.

Without this patch we hit the following error:

[    1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
[    1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
[    1.266807] Workqueue: events deferred_probe_work_func
[    1.271950] Call trace:
[    1.274406]  dump_backtrace+0x0/0x158
[    1.278074]  show_stack+0x14/0x20
[    1.281396]  dump_stack+0xa8/0xcc
[    1.284717]  of_node_release+0xb0/0xc8
[    1.288474]  kobject_put+0x74/0xf0
[    1.291879]  of_node_put+0x14/0x28
[    1.295286]  __of_get_next_child+0x44/0x70
[    1.299387]  of_get_next_child+0x3c/0x60
[    1.303315]  simple_for_each_link+0x1dc/0x230
[    1.307676]  simple_probe+0x80/0x540
[    1.311256]  platform_drv_probe+0x50/0xa0

This patch is based on an earlier version posted by Kuninori Morimoto
and commit message includes explanations from Mark Brown.

https://patchwork.kernel.org/patch/10814255/

Reported-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/generic/simple-card.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c
index 08df261024cf..dc18c4492955 100644
--- a/sound/soc/generic/simple-card.c
+++ b/sound/soc/generic/simple-card.c
@@ -445,7 +445,7 @@ static int simple_for_each_link(struct simple_priv *priv,
 	/* Check if it has dai-link */
 	node = of_get_child_by_name(top, PREFIX "dai-link");
 	if (!node) {
-		node = top;
+		node = of_node_get(top);
 		is_top = 1;
 	}
 
-- 
2.20.1

Applied "ASoC: simple-card: Fix refcount underflow" to the asoc tree

[Mark Brown]

The patch

   ASoC: simple-card: Fix refcount underflow

has been applied to the asoc tree at

   https://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 461d854c0dba3cdf63cce37ffb9423eca0793a47 Mon Sep 17 00:00:00 2001
From: Daniel Baluta <daniel.baluta@nxp.com>
Date: Sat, 16 Feb 2019 10:09:42 +0000
Subject: [PATCH] ASoC: simple-card: Fix refcount underflow

of_get_child_by_name() takes a reference we'll need to drop
later so when we substitute in top we need to take a reference
as well as just assigning.

Without this patch we hit the following error:

[    1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
[    1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
[    1.266807] Workqueue: events deferred_probe_work_func
[    1.271950] Call trace:
[    1.274406]  dump_backtrace+0x0/0x158
[    1.278074]  show_stack+0x14/0x20
[    1.281396]  dump_stack+0xa8/0xcc
[    1.284717]  of_node_release+0xb0/0xc8
[    1.288474]  kobject_put+0x74/0xf0
[    1.291879]  of_node_put+0x14/0x28
[    1.295286]  __of_get_next_child+0x44/0x70
[    1.299387]  of_get_next_child+0x3c/0x60
[    1.303315]  simple_for_each_link+0x1dc/0x230
[    1.307676]  simple_probe+0x80/0x540
[    1.311256]  platform_drv_probe+0x50/0xa0

This patch is based on an earlier version posted by Kuninori Morimoto
and commit message includes explanations from Mark Brown.

https://patchwork.kernel.org/patch/10814255/

Reported-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/generic/simple-card.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c
index 08df261024cf..dc18c4492955 100644
--- a/sound/soc/generic/simple-card.c
+++ b/sound/soc/generic/simple-card.c
@@ -445,7 +445,7 @@ static int simple_for_each_link(struct simple_priv *priv,
 	/* Check if it has dai-link */
 	node = of_get_child_by_name(top, PREFIX "dai-link");
 	if (!node) {
-		node = top;
+		node = of_node_get(top);
 		is_top = 1;
 	}
 
-- 
2.20.1