On Tue, 18 Jun 2019 06:19:15 +0200, Ranjani Sridharan wrote:
On Mon, 2019-06-17 at 23:36 +0200, Takashi Iwai wrote:
On Mon, 17 Jun 2019 22:51:42 +0200, Ranjani Sridharan wrote:
On Mon, 2019-06-17 at 13:36 +0200, Amadeusz Sławiński wrote:
When we unload Skylake driver we may end up calling hdac_component_master_unbind(), it uses acomp->audio_ops, which we set in hdmi_codec_probe(), so we need to set it to NULL in hdmi_codec_remove(), otherwise we will dereference no longer existing pointer.
Hi Amadeusz,
It looks like the audio_ops should be deleted snd_hdac_acomp_exit().
It's a different one. The codec driver registers / de-registers the notifier at its probe/remove, while the controller driver takes care of snd_hdac_acomp_init(). snd_hdac_acomp_exit() is usually not needed to be called explicitly, as it's managed via devres.
Makes sense, thanks Takashi. But I am still wondering why we havent seen this issue with SOF yet. We run the module unload/reload stress test as well and havent seen this yet.
Usually this isn't a problem as the controller is removed at first. But if the codec is unbound at first by some reason, it can be a problem without unregistering, I guess.
Takashi
Thanks, Ranjani
Takashi
Also, this doesnt seem to be the case with when the SOF driver is removed. Could you please give a bit more context on what error you see when this happens?
Thanks, Ranjani
Signed-off-by: Amadeusz Sławiński < amadeuszx.slawinski@linux.intel.com>
sound/soc/codecs/hdac_hdmi.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/sound/soc/codecs/hdac_hdmi.c b/sound/soc/codecs/hdac_hdmi.c index 911bb6e2a1ac..9ee1bff548d8 100644 --- a/sound/soc/codecs/hdac_hdmi.c +++ b/sound/soc/codecs/hdac_hdmi.c @@ -1890,6 +1890,12 @@ static void hdmi_codec_remove(struct snd_soc_component *component) { struct hdac_hdmi_priv *hdmi = snd_soc_component_get_drvdata(component); struct hdac_device *hdev = hdmi->hdev;
- int ret;
- ret = snd_hdac_acomp_register_notifier(hdev->bus, NULL);
- if (ret < 0)
dev_err(&hdev->dev, "notifier unregister failed: err:%d\n",
ret);pm_runtime_disable(&hdev->dev);
}