[alsa-devel] [PATCH] ASoC: dpcm: Make BE prepare possible in suspend state
During suspend/resume, there is a flow that if a driver does not support SNDRV_PCM_INFO_RESUME, it will fail at snd_pcm_resume(), and user space can then issue SNDRV_PCM_IOCTL_PREPARE to let audio continue to play.
However, in dpcm_be_dai_prepare() it only allows BEs to be prepared in state SND_SOC_DPCM_STATE_HW_PARAMS or SND_SOC_DPCM_STATE_STOP. The BE state will then stay in SND_SOC_DPCM_STATE_SUSPEND, consequently dpcm_be_dai_shutdown() is skipped in the end of playback and be_substream->runtime is not cleared while this runtime is actually freed by snd_pcm_detach_substream(). If another suspend comes, a NULL pointer dereference will happen in snd_pcm_suspend() when accessing BE substream's runtime.
Signed-off-by: Koro Chen koro.chen@mediatek.com --- sound/soc/soc-pcm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index 3173958..5c41a58 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -2117,7 +2117,8 @@ int dpcm_be_dai_prepare(struct snd_soc_pcm_runtime *fe, int stream) continue;
if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_PARAMS) && - (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP)) + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) && + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND)) continue;
dev_dbg(be->dev, "ASoC: prepare BE %s\n",
On Wed, 2015-10-28 at 10:15 +0800, Koro Chen wrote:
During suspend/resume, there is a flow that if a driver does not support SNDRV_PCM_INFO_RESUME, it will fail at snd_pcm_resume(), and user space can then issue SNDRV_PCM_IOCTL_PREPARE to let audio continue to play.
However, in dpcm_be_dai_prepare() it only allows BEs to be prepared in state SND_SOC_DPCM_STATE_HW_PARAMS or SND_SOC_DPCM_STATE_STOP. The BE state will then stay in SND_SOC_DPCM_STATE_SUSPEND, consequently dpcm_be_dai_shutdown() is skipped in the end of playback and be_substream->runtime is not cleared while this runtime is actually freed by snd_pcm_detach_substream(). If another suspend comes, a NULL pointer dereference will happen in snd_pcm_suspend() when accessing BE substream's runtime.
Signed-off-by: Koro Chen koro.chen@mediatek.com
Acked-by: Liam Girdwood liam.r.girdwood@linux.intel.com
The patch
ASoC: dpcm: Make BE prepare possible in suspend state
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 0fa0697af79f5c8b080f7a1b8af87fe3b422e746 Mon Sep 17 00:00:00 2001
From: Koro Chen koro.chen@mediatek.com Date: Wed, 28 Oct 2015 10:15:34 +0800 Subject: [PATCH] ASoC: dpcm: Make BE prepare possible in suspend state
During suspend/resume, there is a flow that if a driver does not support SNDRV_PCM_INFO_RESUME, it will fail at snd_pcm_resume(), and user space can then issue SNDRV_PCM_IOCTL_PREPARE to let audio continue to play.
However, in dpcm_be_dai_prepare() it only allows BEs to be prepared in state SND_SOC_DPCM_STATE_HW_PARAMS or SND_SOC_DPCM_STATE_STOP. The BE state will then stay in SND_SOC_DPCM_STATE_SUSPEND, consequently dpcm_be_dai_shutdown() is skipped in the end of playback and be_substream->runtime is not cleared while this runtime is actually freed by snd_pcm_detach_substream(). If another suspend comes, a NULL pointer dereference will happen in snd_pcm_suspend() when accessing BE substream's runtime.
Signed-off-by: Koro Chen koro.chen@mediatek.com Acked-by: Liam Girdwood liam.r.girdwood@linux.intel.com Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/soc-pcm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index 70e4b9d..9cf33b8 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -2068,7 +2068,8 @@ int dpcm_be_dai_prepare(struct snd_soc_pcm_runtime *fe, int stream) continue;
if ((be->dpcm[stream].state != SND_SOC_DPCM_STATE_HW_PARAMS) && - (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP)) + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_STOP) && + (be->dpcm[stream].state != SND_SOC_DPCM_STATE_SUSPEND)) continue;
dev_dbg(be->dev, "ASoC: prepare BE %s\n",
participants (3)
-
Koro Chen -
Liam Girdwood -
Mark Brown