On Tue, Oct 29, 2019 at 09:52:57PM +0100, Takashi Iwai wrote:
On Tue, 29 Oct 2019 20:10:50 +0100, From: Takashi Iwai tiwai@suse.de Subject: [PATCH] ALSA: hda - Fix mutex deadlock in HDMI codec driver
The commit ade49db337a9 ("ALSA: hda/hdmi - Allow audio component for AMD/ATI and Nvidia HDMI") introduced the spec->pcm_lock mutex lock to the whole generic_hdmi_init() function for avoiding the race with the audio component registration. However, this caused a dead lock when the unsolicited event is handled without the audio component, as the codec gets runtime-resumed in hdmi_present_sense() which is already inside the spec->pcm_lock in its caller.
For avoiding this deadlock, add a new mutex only for the audio component binding that is used in both generic_hdmi_init() and the audio notifier registration where the jack callbacks are handled / re-registered.
Fixes: ade49db337a9 ("ALSA: hda/hdmi - Allow audio component for AMD/ATI and Nvidia HDMI") Reported-by: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Takashi Iwai tiwai@suse.de
sound/pci/hda/patch_hdmi.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c index 795cbda32cbb..d9b5ba361409 100644 --- a/sound/pci/hda/patch_hdmi.c +++ b/sound/pci/hda/patch_hdmi.c @@ -145,6 +145,7 @@ struct hdmi_spec { struct snd_array pins; /* struct hdmi_spec_per_pin */ struct hdmi_pcm pcm_rec[16]; struct mutex pcm_lock;
- struct mutex bind_lock; /* for audio component binding */
Missing mutex_init() for this guy.
Tested-by: Ville Syrjälä ville.syrjala@linux.intel.com
/* pcm_bitmap means which pcms have been assigned to pins*/ unsigned long pcm_bitmap; int pcm_used; /* counter of pcm_rec[] */ @@ -2258,7 +2259,7 @@ static int generic_hdmi_init(struct hda_codec *codec) struct hdmi_spec *spec = codec->spec; int pin_idx;
- mutex_lock(&spec->pcm_lock);
- mutex_lock(&spec->bind_lock); spec->use_jack_detect = !codec->jackpoll_interval; for (pin_idx = 0; pin_idx < spec->num_pins; pin_idx++) { struct hdmi_spec_per_pin *per_pin = get_pin(spec, pin_idx);
@@ -2275,7 +2276,7 @@ static int generic_hdmi_init(struct hda_codec *codec) snd_hda_jack_detect_enable_callback(codec, pin_nid, jack_callback); }
- mutex_unlock(&spec->pcm_lock);
- mutex_unlock(&spec->bind_lock); return 0;
}
@@ -2451,7 +2452,7 @@ static void generic_acomp_notifier_set(struct drm_audio_component *acomp, int i;
spec = container_of(acomp->audio_ops, struct hdmi_spec, drm_audio_ops);
- mutex_lock(&spec->pcm_lock);
- mutex_lock(&spec->bind_lock); spec->use_acomp_notifier = use_acomp; spec->codec->relaxed_resume = use_acomp; /* reprogram each jack detection logic depending on the notifier */
@@ -2461,7 +2462,7 @@ static void generic_acomp_notifier_set(struct drm_audio_component *acomp, get_pin(spec, i)->pin_nid, use_acomp); }
- mutex_unlock(&spec->pcm_lock);
- mutex_unlock(&spec->bind_lock);
}
/* enable / disable the notifier via master bind / unbind */
2.16.4