diff options
| author | Takashi Iwai <tiwai@suse.de> | 2017-08-25 13:04:07 +0300 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2017-09-27 20:08:52 +0300 |
| commit | 5d61f0ba6524dcbad198126e5793157c8afdea91 (patch) | |
| tree | 279819f50b58c4c38efb13f3a41414354ecdb05d /sound/soc/soc-pcm.c | |
| parent | 2bd6bf03f4c1c59381d62c61d03f6cc3fe71f66e (diff) | |
| download | linux-5d61f0ba6524dcbad198126e5793157c8afdea91.tar.xz | |
ASoC: pcm: Sync delayed work before releasing resources
When ASoC driver is unbound dynamically during its operation (i.e. a
kind of hot-unplug), we may hit Oops due to the resource access after
the release by a delayed work, something like:
Unable to handle kernel paging request at virtual address dead000000000220
....
PC is at soc_dapm_dai_stream_event.isra.14+0x20/0xd0
LR is at snd_soc_dapm_stream_event+0x74/0xa8
....
[<ffff000008715610>] soc_dapm_dai_stream_event.isra.14+0x20/0xd0
[<ffff00000871989c>] snd_soc_dapm_stream_event+0x74/0xa8
[<ffff00000871b23c>] close_delayed_work+0x3c/0x50
[<ffff0000080bbd6c>] process_one_work+0x1ac/0x318
[<ffff0000080bbf20>] worker_thread+0x48/0x420
[<ffff0000080c201c>] kthread+0xfc/0x128
[<ffff0000080842f0>] ret_from_fork+0x10/0x18
For fixing the race, this patch adds a sync-point in pcm private_free
callback to finish the delayed work before actually releasing the
resources.
Reported-by: Hiep Cao Minh <cm-hiep@jinso.co.jp>
Reported-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'sound/soc/soc-pcm.c')
| -rw-r--r-- | sound/soc/soc-pcm.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c index 94b88b897c3b..c0f0b09cb433 100644 --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -2632,6 +2632,17 @@ static int dpcm_fe_dai_close(struct snd_pcm_substream *fe_substream) return ret; } +static void soc_pcm_private_free(struct snd_pcm *pcm) +{ + struct snd_soc_pcm_runtime *rtd = pcm->private_data; + struct snd_soc_platform *platform = rtd->platform; + + /* need to sync the delayed work before releasing resources */ + flush_delayed_work(&rtd->delayed_work); + if (platform->driver->pcm_free) + platform->driver->pcm_free(pcm); +} + /* create a new pcm */ int soc_new_pcm(struct snd_soc_pcm_runtime *rtd, int num) { @@ -2757,7 +2768,7 @@ int soc_new_pcm(struct snd_soc_pcm_runtime *rtd, int num) } } - pcm->private_free = platform->driver->pcm_free; + pcm->private_free = soc_pcm_private_free; out: dev_info(rtd->card->dev, "%s <-> %s mapping ok\n", (rtd->num_codecs > 1) ? "multicodec" : rtd->codec_dai->name, |