[PATCH for v6.13-rc] ASoC: SOF: Intel: hda-dai: Do not release the link DMA on STOP

[PATCH for v6.13-rc] ASoC: SOF: Intel: hda-dai: Do not release the link DMA on STOP

[Peter Ujfalusi]

The linkDMA should not be released on stop trigger since a stream re-start
might happen without closing of the stream. This leaves a short time for
other streams to 'steal' the linkDMA since it has been released.

This issue is not easy to reproduce under normal conditions as usually
after stop the stream is closed, or the same stream is restarted, but if
another stream got in between the stop and start, like this:
aplay -Dhw:0,3 -c2 -r48000 -fS32_LE /dev/zero -d 120
CTRL+z
aplay -Dhw:0,0 -c2 -r48000 -fS32_LE /dev/zero -d 120

then the link DMA channels will be mixed up, resulting firmware error or
crash.

Fixes: ab5593793e90 ("ASoC: SOF: Intel: hda: Always clean up link DMA during stop")
Cc: stable@vger.kernel.org
Closes: https://github.com/thesofproject/sof/issues/9695
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
---
 sound/soc/sof/intel/hda-dai.c | 25 +++++++++++++++++++------
 sound/soc/sof/intel/hda.h     |  2 --
 2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/sound/soc/sof/intel/hda-dai.c b/sound/soc/sof/intel/hda-dai.c
index 1b218d77f292..da12aabc1bb8 100644
--- a/sound/soc/sof/intel/hda-dai.c
+++ b/sound/soc/sof/intel/hda-dai.c
@@ -103,8 +103,10 @@ hda_dai_get_ops(struct snd_pcm_substream *substream, struct snd_soc_dai *cpu_dai
 	return sdai->platform_private;
 }
 
-int hda_link_dma_cleanup(struct snd_pcm_substream *substream, struct hdac_ext_stream *hext_stream,
-			 struct snd_soc_dai *cpu_dai)
+static int
+hda_link_dma_cleanup(struct snd_pcm_substream *substream,
+		     struct hdac_ext_stream *hext_stream,
+		     struct snd_soc_dai *cpu_dai, bool release)
 {
 	const struct hda_dai_widget_dma_ops *ops = hda_dai_get_ops(substream, cpu_dai);
 	struct sof_intel_hda_stream *hda_stream;
@@ -128,6 +130,17 @@ int hda_link_dma_cleanup(struct snd_pcm_substream *substream, struct hdac_ext_st
 		snd_hdac_ext_bus_link_clear_stream_id(hlink, stream_tag);
 	}
 
+	if (!release) {
+		/*
+		 * Force stream reconfiguration without releasing the channel on
+		 * subsequent stream restart (without free), including LinkDMA
+		 * reset.
+		 * The stream is released via hda_dai_hw_free()
+		 */
+		hext_stream->link_prepared = 0;
+		return 0;
+	}
+
 	if (ops->release_hext_stream)
 		ops->release_hext_stream(sdev, cpu_dai, substream);
 
@@ -211,7 +224,7 @@ static int __maybe_unused hda_dai_hw_free(struct snd_pcm_substream *substream,
 	if (!hext_stream)
 		return 0;
 
-	return hda_link_dma_cleanup(substream, hext_stream, cpu_dai);
+	return hda_link_dma_cleanup(substream, hext_stream, cpu_dai, true);
 }
 
 static int __maybe_unused hda_dai_hw_params_data(struct snd_pcm_substream *substream,
@@ -304,7 +317,8 @@ static int __maybe_unused hda_dai_trigger(struct snd_pcm_substream *substream, i
 	switch (cmd) {
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
-		ret = hda_link_dma_cleanup(substream, hext_stream, dai);
+		ret = hda_link_dma_cleanup(substream, hext_stream, dai,
+					   cmd == SNDRV_PCM_TRIGGER_STOP ? false : true);
 		if (ret < 0) {
 			dev_err(sdev->dev, "%s: failed to clean up link DMA\n", __func__);
 			return ret;
@@ -672,8 +686,7 @@ static int hda_dai_suspend(struct hdac_bus *bus)
 			}
 
 			ret = hda_link_dma_cleanup(hext_stream->link_substream,
-						   hext_stream,
-						   cpu_dai);
+						   hext_stream, cpu_dai, true);
 			if (ret < 0)
 				return ret;
 		}
diff --git a/sound/soc/sof/intel/hda.h b/sound/soc/sof/intel/hda.h
index 22bd9c3c8216..ee4ccc1a5490 100644
--- a/sound/soc/sof/intel/hda.h
+++ b/sound/soc/sof/intel/hda.h
@@ -1038,8 +1038,6 @@ const struct hda_dai_widget_dma_ops *
 hda_select_dai_widget_ops(struct snd_sof_dev *sdev, struct snd_sof_widget *swidget);
 int hda_dai_config(struct snd_soc_dapm_widget *w, unsigned int flags,
 		   struct snd_sof_dai_config_data *data);
-int hda_link_dma_cleanup(struct snd_pcm_substream *substream, struct hdac_ext_stream *hext_stream,
-			 struct snd_soc_dai *cpu_dai);
 
 static inline struct snd_sof_dev *widget_to_sdev(struct snd_soc_dapm_widget *w)
 {
-- 
2.47.1

Re: [PATCH for v6.13-rc] ASoC: SOF: Intel: hda-dai: Do not release the link DMA on STOP

[Mark Brown]

On Tue, 17 Dec 2024 11:10:19 +0200, Peter Ujfalusi wrote:
> The linkDMA should not be released on stop trigger since a stream re-start
> might happen without closing of the stream. This leaves a short time for
> other streams to 'steal' the linkDMA since it has been released.
> 
> This issue is not easy to reproduce under normal conditions as usually
> after stop the stream is closed, or the same stream is restarted, but if
> another stream got in between the stop and start, like this:
> aplay -Dhw:0,3 -c2 -r48000 -fS32_LE /dev/zero -d 120
> CTRL+z
> aplay -Dhw:0,0 -c2 -r48000 -fS32_LE /dev/zero -d 120
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/1] ASoC: SOF: Intel: hda-dai: Do not release the link DMA on STOP
      commit: e8d0ba147d901022bcb69da8d8fd817f84e9f3ca

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