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* [PATCH 0/3] ASoC: stm32: spdifrx: fix race conditions
@ 2019-12-04 15:43 Olivier Moysan
  2019-12-04 15:43 ` [PATCH 1/3] ASoC: stm32: spdifrx: fix inconsistent lock state Olivier Moysan
                   ` (2 more replies)
  0 siblings, 3 replies; 7+ messages in thread
From: Olivier Moysan @ 2019-12-04 15:43 UTC (permalink / raw)
  To: lgirdwood, broonie, perex, tiwai, mcoquelin.stm32,
	alexandre.torgue, alsa-devel, linux-arm-kernel, linux-stm32,
	linux-kernel, olivier.moysan

This patchset fixes some race conditions on STM32 SPDIFRX driver.

Olivier Moysan (3):
  ASoC: stm32: spdifrx: fix inconsistent lock state
  ASoC: stm32: spdifrx: fix race condition in irq handler
  ASoC: stm32: spdifrx: fix input pin state management

 sound/soc/stm/stm32_spdifrx.c | 40 +++++++++++++++++++++++------------
 1 file changed, 26 insertions(+), 14 deletions(-)

-- 
2.17.1


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^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH 1/3] ASoC: stm32: spdifrx: fix inconsistent lock state
  2019-12-04 15:43 [PATCH 0/3] ASoC: stm32: spdifrx: fix race conditions Olivier Moysan
@ 2019-12-04 15:43 ` Olivier Moysan
  2019-12-25  0:09   ` Applied "ASoC: stm32: spdifrx: fix inconsistent lock state" to the asoc tree Mark Brown
  2019-12-04 15:43 ` [PATCH 2/3] ASoC: stm32: spdifrx: fix race condition in irq handler Olivier Moysan
  2019-12-04 15:43 ` [PATCH 3/3] ASoC: stm32: spdifrx: fix input pin state management Olivier Moysan
  2 siblings, 1 reply; 7+ messages in thread
From: Olivier Moysan @ 2019-12-04 15:43 UTC (permalink / raw)
  To: lgirdwood, broonie, perex, tiwai, mcoquelin.stm32,
	alexandre.torgue, alsa-devel, linux-arm-kernel, linux-stm32,
	linux-kernel, olivier.moysan

In current spdifrx driver locks may be requested as follows:
- request lock on iec capture control, when starting synchronization.
- request lock in interrupt context, when spdifrx stop is called
from IRQ handler.

Take lock with IRQs disabled, to avoid the possible deadlock.

Lockdep report:
[   74.278059] ================================
[   74.282306] WARNING: inconsistent lock state
[   74.290120] --------------------------------
...
[   74.314373]        CPU0
[   74.314377]        ----
[   74.314381]   lock(&(&spdifrx->lock)->rlock);
[   74.314396]   <Interrupt>
[   74.314400]     lock(&(&spdifrx->lock)->rlock);

Fixes: 03e4d5d56fa5 ("ASoC: stm32: Add SPDIFRX support")

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
---
 sound/soc/stm/stm32_spdifrx.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index 3fd28ee01675..9c6beb610c17 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -320,6 +320,7 @@ static void stm32_spdifrx_dma_ctrl_stop(struct stm32_spdifrx_data *spdifrx)
 static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 {
 	int cr, cr_mask, imr, ret;
+	unsigned long flags;
 
 	/* Enable IRQs */
 	imr = SPDIFRX_IMR_IFEIE | SPDIFRX_IMR_SYNCDIE | SPDIFRX_IMR_PERRIE;
@@ -327,7 +328,7 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 	if (ret)
 		return ret;
 
-	spin_lock(&spdifrx->lock);
+	spin_lock_irqsave(&spdifrx->lock, flags);
 
 	spdifrx->refcount++;
 
@@ -362,7 +363,7 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 				"Failed to start synchronization\n");
 	}
 
-	spin_unlock(&spdifrx->lock);
+	spin_unlock_irqrestore(&spdifrx->lock, flags);
 
 	return ret;
 }
@@ -370,11 +371,12 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
 {
 	int cr, cr_mask, reg;
+	unsigned long flags;
 
-	spin_lock(&spdifrx->lock);
+	spin_lock_irqsave(&spdifrx->lock, flags);
 
 	if (--spdifrx->refcount) {
-		spin_unlock(&spdifrx->lock);
+		spin_unlock_irqrestore(&spdifrx->lock, flags);
 		return;
 	}
 
@@ -393,7 +395,7 @@ static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_DR, &reg);
 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CSR, &reg);
 
-	spin_unlock(&spdifrx->lock);
+	spin_unlock_irqrestore(&spdifrx->lock, flags);
 }
 
 static int stm32_spdifrx_dma_ctrl_register(struct device *dev,
-- 
2.17.1


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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* [PATCH 2/3] ASoC: stm32: spdifrx: fix race condition in irq handler
  2019-12-04 15:43 [PATCH 0/3] ASoC: stm32: spdifrx: fix race conditions Olivier Moysan
  2019-12-04 15:43 ` [PATCH 1/3] ASoC: stm32: spdifrx: fix inconsistent lock state Olivier Moysan
@ 2019-12-04 15:43 ` Olivier Moysan
  2019-12-25  0:09   ` Applied "ASoC: stm32: spdifrx: fix race condition in irq handler" to the asoc tree Mark Brown
  2019-12-04 15:43 ` [PATCH 3/3] ASoC: stm32: spdifrx: fix input pin state management Olivier Moysan
  2 siblings, 1 reply; 7+ messages in thread
From: Olivier Moysan @ 2019-12-04 15:43 UTC (permalink / raw)
  To: lgirdwood, broonie, perex, tiwai, mcoquelin.stm32,
	alexandre.torgue, alsa-devel, linux-arm-kernel, linux-stm32,
	linux-kernel, olivier.moysan

When snd_pcm_stop() is called in interrupt routine,
substream context may have already been released.
Add protection on substream context.

Fixes: 03e4d5d56fa5 ("ASoC: stm32: Add SPDIFRX support")

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
---
 sound/soc/stm/stm32_spdifrx.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index 9c6beb610c17..3cb8e6db3eeb 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -220,6 +220,7 @@
  * @slave_config: dma slave channel runtime config pointer
  * @phys_addr: SPDIFRX registers physical base address
  * @lock: synchronization enabling lock
+ * @irq_lock: prevent race condition with IRQ on stream state
  * @cs: channel status buffer
  * @ub: user data buffer
  * @irq: SPDIFRX interrupt line
@@ -240,6 +241,7 @@ struct stm32_spdifrx_data {
 	struct dma_slave_config slave_config;
 	dma_addr_t phys_addr;
 	spinlock_t lock;  /* Sync enabling lock */
+	spinlock_t irq_lock; /* Prevent race condition on stream state */
 	unsigned char cs[SPDIFRX_CS_BYTES_NB];
 	unsigned char ub[SPDIFRX_UB_BYTES_NB];
 	int irq;
@@ -667,7 +669,6 @@ static const struct regmap_config stm32_h7_spdifrx_regmap_conf = {
 static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
 {
 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)devid;
-	struct snd_pcm_substream *substream = spdifrx->substream;
 	struct platform_device *pdev = spdifrx->pdev;
 	unsigned int cr, mask, sr, imr;
 	unsigned int flags, sync_state;
@@ -747,14 +748,19 @@ static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
 			return IRQ_HANDLED;
 		}
 
-		if (substream)
-			snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
+		spin_lock(&spdifrx->irq_lock);
+		if (spdifrx->substream)
+			snd_pcm_stop(spdifrx->substream,
+				     SNDRV_PCM_STATE_DISCONNECTED);
+		spin_unlock(&spdifrx->irq_lock);
 
 		return IRQ_HANDLED;
 	}
 
-	if (err_xrun && substream)
-		snd_pcm_stop_xrun(substream);
+	spin_lock(&spdifrx->irq_lock);
+	if (err_xrun && spdifrx->substream)
+		snd_pcm_stop_xrun(spdifrx->substream);
+	spin_unlock(&spdifrx->irq_lock);
 
 	return IRQ_HANDLED;
 }
@@ -763,9 +769,12 @@ static int stm32_spdifrx_startup(struct snd_pcm_substream *substream,
 				 struct snd_soc_dai *cpu_dai)
 {
 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+	unsigned long flags;
 	int ret;
 
+	spin_lock_irqsave(&spdifrx->irq_lock, flags);
 	spdifrx->substream = substream;
+	spin_unlock_irqrestore(&spdifrx->irq_lock, flags);
 
 	ret = clk_prepare_enable(spdifrx->kclk);
 	if (ret)
@@ -841,8 +850,12 @@ static void stm32_spdifrx_shutdown(struct snd_pcm_substream *substream,
 				   struct snd_soc_dai *cpu_dai)
 {
 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+	unsigned long flags;
 
+	spin_lock_irqsave(&spdifrx->irq_lock, flags);
 	spdifrx->substream = NULL;
+	spin_unlock_irqrestore(&spdifrx->irq_lock, flags);
+
 	clk_disable_unprepare(spdifrx->kclk);
 }
 
@@ -946,6 +959,7 @@ static int stm32_spdifrx_probe(struct platform_device *pdev)
 	spdifrx->pdev = pdev;
 	init_completion(&spdifrx->cs_completion);
 	spin_lock_init(&spdifrx->lock);
+	spin_lock_init(&spdifrx->irq_lock);
 
 	platform_set_drvdata(pdev, spdifrx);
 
-- 
2.17.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* [PATCH 3/3] ASoC: stm32: spdifrx: fix input pin state management
  2019-12-04 15:43 [PATCH 0/3] ASoC: stm32: spdifrx: fix race conditions Olivier Moysan
  2019-12-04 15:43 ` [PATCH 1/3] ASoC: stm32: spdifrx: fix inconsistent lock state Olivier Moysan
  2019-12-04 15:43 ` [PATCH 2/3] ASoC: stm32: spdifrx: fix race condition in irq handler Olivier Moysan
@ 2019-12-04 15:43 ` Olivier Moysan
  2019-12-25  0:09   ` Applied "ASoC: stm32: spdifrx: fix input pin state management" to the asoc tree Mark Brown
  2 siblings, 1 reply; 7+ messages in thread
From: Olivier Moysan @ 2019-12-04 15:43 UTC (permalink / raw)
  To: lgirdwood, broonie, perex, tiwai, mcoquelin.stm32,
	alexandre.torgue, alsa-devel, linux-arm-kernel, linux-stm32,
	linux-kernel, olivier.moysan

Changing input state in iec capture control is not safe,
as the pin state may be changed concurrently by ASoC
framework.
Remove pin state handling in iec capture control.

Note: This introduces a restriction on capture control,
when pin sleep state is defined in device tree. In this case
channel status can be captured only when an audio stream
capture is active.

Fixes: f68c2a682d44 ("ASoC: stm32: spdifrx: add power management")

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
---
 sound/soc/stm/stm32_spdifrx.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index 3cb8e6db3eeb..3769d9ce5dbe 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -12,7 +12,6 @@
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
-#include <linux/pinctrl/consumer.h>
 #include <linux/regmap.h>
 #include <linux/reset.h>
 
@@ -484,8 +483,6 @@ static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
 	memset(spdifrx->cs, 0, SPDIFRX_CS_BYTES_NB);
 	memset(spdifrx->ub, 0, SPDIFRX_UB_BYTES_NB);
 
-	pinctrl_pm_select_default_state(&spdifrx->pdev->dev);
-
 	ret = stm32_spdifrx_dma_ctrl_start(spdifrx);
 	if (ret < 0)
 		return ret;
@@ -517,7 +514,6 @@ static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
 
 end:
 	clk_disable_unprepare(spdifrx->kclk);
-	pinctrl_pm_select_sleep_state(&spdifrx->pdev->dev);
 
 	return ret;
 }
-- 
2.17.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* Applied "ASoC: stm32: spdifrx: fix input pin state management" to the asoc tree
  2019-12-04 15:43 ` [PATCH 3/3] ASoC: stm32: spdifrx: fix input pin state management Olivier Moysan
@ 2019-12-25  0:09   ` Mark Brown
  0 siblings, 0 replies; 7+ messages in thread
From: Mark Brown @ 2019-12-25  0:09 UTC (permalink / raw)
  To: Olivier Moysan
  Cc: alsa-devel, olivier.moysan, alexandre.torgue, tiwai,
	linux-kernel, lgirdwood, Mark Brown, mcoquelin.stm32, perex,
	linux-stm32, linux-arm-kernel

The patch

   ASoC: stm32: spdifrx: fix input pin state management

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 3b7658679d88b5628939f9bdc8e613f79cd821f9 Mon Sep 17 00:00:00 2001
From: Olivier Moysan <olivier.moysan@st.com>
Date: Wed, 4 Dec 2019 16:43:33 +0100
Subject: [PATCH] ASoC: stm32: spdifrx: fix input pin state management

Changing input state in iec capture control is not safe,
as the pin state may be changed concurrently by ASoC
framework.
Remove pin state handling in iec capture control.

Note: This introduces a restriction on capture control,
when pin sleep state is defined in device tree. In this case
channel status can be captured only when an audio stream
capture is active.

Fixes: f68c2a682d44 ("ASoC: stm32: spdifrx: add power management")

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Link: https://lore.kernel.org/r/20191204154333.7152-4-olivier.moysan@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/stm/stm32_spdifrx.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index 3cb8e6db3eeb..3769d9ce5dbe 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -12,7 +12,6 @@
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/of_platform.h>
-#include <linux/pinctrl/consumer.h>
 #include <linux/regmap.h>
 #include <linux/reset.h>
 
@@ -484,8 +483,6 @@ static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
 	memset(spdifrx->cs, 0, SPDIFRX_CS_BYTES_NB);
 	memset(spdifrx->ub, 0, SPDIFRX_UB_BYTES_NB);
 
-	pinctrl_pm_select_default_state(&spdifrx->pdev->dev);
-
 	ret = stm32_spdifrx_dma_ctrl_start(spdifrx);
 	if (ret < 0)
 		return ret;
@@ -517,7 +514,6 @@ static int stm32_spdifrx_get_ctrl_data(struct stm32_spdifrx_data *spdifrx)
 
 end:
 	clk_disable_unprepare(spdifrx->kclk);
-	pinctrl_pm_select_sleep_state(&spdifrx->pdev->dev);
 
 	return ret;
 }
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* Applied "ASoC: stm32: spdifrx: fix race condition in irq handler" to the asoc tree
  2019-12-04 15:43 ` [PATCH 2/3] ASoC: stm32: spdifrx: fix race condition in irq handler Olivier Moysan
@ 2019-12-25  0:09   ` Mark Brown
  0 siblings, 0 replies; 7+ messages in thread
From: Mark Brown @ 2019-12-25  0:09 UTC (permalink / raw)
  To: Olivier Moysan
  Cc: alsa-devel, olivier.moysan, alexandre.torgue, tiwai,
	linux-kernel, lgirdwood, Mark Brown, mcoquelin.stm32, perex,
	linux-stm32, linux-arm-kernel

The patch

   ASoC: stm32: spdifrx: fix race condition in irq handler

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 86e1956af4c863d653136fd6e5694adf2054dbaa Mon Sep 17 00:00:00 2001
From: Olivier Moysan <olivier.moysan@st.com>
Date: Wed, 4 Dec 2019 16:43:32 +0100
Subject: [PATCH] ASoC: stm32: spdifrx: fix race condition in irq handler

When snd_pcm_stop() is called in interrupt routine,
substream context may have already been released.
Add protection on substream context.

Fixes: 03e4d5d56fa5 ("ASoC: stm32: Add SPDIFRX support")

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Link: https://lore.kernel.org/r/20191204154333.7152-3-olivier.moysan@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/stm/stm32_spdifrx.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index 9c6beb610c17..3cb8e6db3eeb 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -220,6 +220,7 @@
  * @slave_config: dma slave channel runtime config pointer
  * @phys_addr: SPDIFRX registers physical base address
  * @lock: synchronization enabling lock
+ * @irq_lock: prevent race condition with IRQ on stream state
  * @cs: channel status buffer
  * @ub: user data buffer
  * @irq: SPDIFRX interrupt line
@@ -240,6 +241,7 @@ struct stm32_spdifrx_data {
 	struct dma_slave_config slave_config;
 	dma_addr_t phys_addr;
 	spinlock_t lock;  /* Sync enabling lock */
+	spinlock_t irq_lock; /* Prevent race condition on stream state */
 	unsigned char cs[SPDIFRX_CS_BYTES_NB];
 	unsigned char ub[SPDIFRX_UB_BYTES_NB];
 	int irq;
@@ -667,7 +669,6 @@ static const struct regmap_config stm32_h7_spdifrx_regmap_conf = {
 static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
 {
 	struct stm32_spdifrx_data *spdifrx = (struct stm32_spdifrx_data *)devid;
-	struct snd_pcm_substream *substream = spdifrx->substream;
 	struct platform_device *pdev = spdifrx->pdev;
 	unsigned int cr, mask, sr, imr;
 	unsigned int flags, sync_state;
@@ -747,14 +748,19 @@ static irqreturn_t stm32_spdifrx_isr(int irq, void *devid)
 			return IRQ_HANDLED;
 		}
 
-		if (substream)
-			snd_pcm_stop(substream, SNDRV_PCM_STATE_DISCONNECTED);
+		spin_lock(&spdifrx->irq_lock);
+		if (spdifrx->substream)
+			snd_pcm_stop(spdifrx->substream,
+				     SNDRV_PCM_STATE_DISCONNECTED);
+		spin_unlock(&spdifrx->irq_lock);
 
 		return IRQ_HANDLED;
 	}
 
-	if (err_xrun && substream)
-		snd_pcm_stop_xrun(substream);
+	spin_lock(&spdifrx->irq_lock);
+	if (err_xrun && spdifrx->substream)
+		snd_pcm_stop_xrun(spdifrx->substream);
+	spin_unlock(&spdifrx->irq_lock);
 
 	return IRQ_HANDLED;
 }
@@ -763,9 +769,12 @@ static int stm32_spdifrx_startup(struct snd_pcm_substream *substream,
 				 struct snd_soc_dai *cpu_dai)
 {
 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+	unsigned long flags;
 	int ret;
 
+	spin_lock_irqsave(&spdifrx->irq_lock, flags);
 	spdifrx->substream = substream;
+	spin_unlock_irqrestore(&spdifrx->irq_lock, flags);
 
 	ret = clk_prepare_enable(spdifrx->kclk);
 	if (ret)
@@ -841,8 +850,12 @@ static void stm32_spdifrx_shutdown(struct snd_pcm_substream *substream,
 				   struct snd_soc_dai *cpu_dai)
 {
 	struct stm32_spdifrx_data *spdifrx = snd_soc_dai_get_drvdata(cpu_dai);
+	unsigned long flags;
 
+	spin_lock_irqsave(&spdifrx->irq_lock, flags);
 	spdifrx->substream = NULL;
+	spin_unlock_irqrestore(&spdifrx->irq_lock, flags);
+
 	clk_disable_unprepare(spdifrx->kclk);
 }
 
@@ -946,6 +959,7 @@ static int stm32_spdifrx_probe(struct platform_device *pdev)
 	spdifrx->pdev = pdev;
 	init_completion(&spdifrx->cs_completion);
 	spin_lock_init(&spdifrx->lock);
+	spin_lock_init(&spdifrx->irq_lock);
 
 	platform_set_drvdata(pdev, spdifrx);
 
-- 
2.20.1


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^ permalink raw reply related	[flat|nested] 7+ messages in thread

* Applied "ASoC: stm32: spdifrx: fix inconsistent lock state" to the asoc tree
  2019-12-04 15:43 ` [PATCH 1/3] ASoC: stm32: spdifrx: fix inconsistent lock state Olivier Moysan
@ 2019-12-25  0:09   ` Mark Brown
  0 siblings, 0 replies; 7+ messages in thread
From: Mark Brown @ 2019-12-25  0:09 UTC (permalink / raw)
  To: Olivier Moysan
  Cc: alsa-devel, olivier.moysan, alexandre.torgue, tiwai,
	linux-kernel, lgirdwood, Mark Brown, mcoquelin.stm32, perex,
	linux-stm32, linux-arm-kernel

The patch

   ASoC: stm32: spdifrx: fix inconsistent lock state

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 2859b1784031b5709446af8f6039c467f136e67d Mon Sep 17 00:00:00 2001
From: Olivier Moysan <olivier.moysan@st.com>
Date: Wed, 4 Dec 2019 16:43:31 +0100
Subject: [PATCH] ASoC: stm32: spdifrx: fix inconsistent lock state

In current spdifrx driver locks may be requested as follows:
- request lock on iec capture control, when starting synchronization.
- request lock in interrupt context, when spdifrx stop is called
from IRQ handler.

Take lock with IRQs disabled, to avoid the possible deadlock.

Lockdep report:
[   74.278059] ================================
[   74.282306] WARNING: inconsistent lock state
[   74.290120] --------------------------------
...
[   74.314373]        CPU0
[   74.314377]        ----
[   74.314381]   lock(&(&spdifrx->lock)->rlock);
[   74.314396]   <Interrupt>
[   74.314400]     lock(&(&spdifrx->lock)->rlock);

Fixes: 03e4d5d56fa5 ("ASoC: stm32: Add SPDIFRX support")

Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Link: https://lore.kernel.org/r/20191204154333.7152-2-olivier.moysan@st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 sound/soc/stm/stm32_spdifrx.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/sound/soc/stm/stm32_spdifrx.c b/sound/soc/stm/stm32_spdifrx.c
index 3fd28ee01675..9c6beb610c17 100644
--- a/sound/soc/stm/stm32_spdifrx.c
+++ b/sound/soc/stm/stm32_spdifrx.c
@@ -320,6 +320,7 @@ static void stm32_spdifrx_dma_ctrl_stop(struct stm32_spdifrx_data *spdifrx)
 static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 {
 	int cr, cr_mask, imr, ret;
+	unsigned long flags;
 
 	/* Enable IRQs */
 	imr = SPDIFRX_IMR_IFEIE | SPDIFRX_IMR_SYNCDIE | SPDIFRX_IMR_PERRIE;
@@ -327,7 +328,7 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 	if (ret)
 		return ret;
 
-	spin_lock(&spdifrx->lock);
+	spin_lock_irqsave(&spdifrx->lock, flags);
 
 	spdifrx->refcount++;
 
@@ -362,7 +363,7 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 				"Failed to start synchronization\n");
 	}
 
-	spin_unlock(&spdifrx->lock);
+	spin_unlock_irqrestore(&spdifrx->lock, flags);
 
 	return ret;
 }
@@ -370,11 +371,12 @@ static int stm32_spdifrx_start_sync(struct stm32_spdifrx_data *spdifrx)
 static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
 {
 	int cr, cr_mask, reg;
+	unsigned long flags;
 
-	spin_lock(&spdifrx->lock);
+	spin_lock_irqsave(&spdifrx->lock, flags);
 
 	if (--spdifrx->refcount) {
-		spin_unlock(&spdifrx->lock);
+		spin_unlock_irqrestore(&spdifrx->lock, flags);
 		return;
 	}
 
@@ -393,7 +395,7 @@ static void stm32_spdifrx_stop(struct stm32_spdifrx_data *spdifrx)
 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_DR, &reg);
 	regmap_read(spdifrx->regmap, STM32_SPDIFRX_CSR, &reg);
 
-	spin_unlock(&spdifrx->lock);
+	spin_unlock_irqrestore(&spdifrx->lock, flags);
 }
 
 static int stm32_spdifrx_dma_ctrl_register(struct device *dev,
-- 
2.20.1


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^ permalink raw reply related	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2019-12-25  0:09 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-12-04 15:43 [PATCH 0/3] ASoC: stm32: spdifrx: fix race conditions Olivier Moysan
2019-12-04 15:43 ` [PATCH 1/3] ASoC: stm32: spdifrx: fix inconsistent lock state Olivier Moysan
2019-12-25  0:09   ` Applied "ASoC: stm32: spdifrx: fix inconsistent lock state" to the asoc tree Mark Brown
2019-12-04 15:43 ` [PATCH 2/3] ASoC: stm32: spdifrx: fix race condition in irq handler Olivier Moysan
2019-12-25  0:09   ` Applied "ASoC: stm32: spdifrx: fix race condition in irq handler" to the asoc tree Mark Brown
2019-12-04 15:43 ` [PATCH 3/3] ASoC: stm32: spdifrx: fix input pin state management Olivier Moysan
2019-12-25  0:09   ` Applied "ASoC: stm32: spdifrx: fix input pin state management" to the asoc tree Mark Brown

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