On Wed, 29 Jul 2020 17:03:22 +0200, Ranjani Sridharan wrote: > > On Wed, 2020-07-29 at 09:48 +0200, Takashi Iwai wrote: > > On Wed, 29 Jul 2020 01:10:11 +0200, > > Ranjani Sridharan wrote: > > > When the ASoC card registration fails and the codec component > > > driver > > > never probes, the codec device is not initialized and therefore > > > memory for codec->wcaps is not allocated. This results in a NULL > > > pointer > > > dereference when the codec driver suspend callback is invoked > > > during > > > system suspend. Fix this by returning without performing any > > > actions > > > during codec suspend/resume if the card was not registered > > > successfully. > > > > > > Reviewed-by: Pierre-Louis Bossart < > > > pierre-louis.bossart@xxxxxxxxxxxxxxx> > > > Signed-off-by: Ranjani Sridharan <ranjani.sridharan@xxxxxxxxxxxxxxx > > > > > > > > The code changes look OK to apply, but I still wonder how the runtime > > PM gets invoked even if the device is not instantiated properly? > Hi Takashi, > > Its not runtime PM suspend but rather the system PM suspend callback > that is invoked when the system is suspended that ends up callling the > the runtime PM callback. So, the sequence is: > hda_codec_pm_suspend() > -> pm_runtime_force_suspend() > -> hda_codec_runtime_suspend() OK, but the problem is still same. The basic problem is that the hda_codec_driver_probe() is called for the hda_codec object that hasn't been initialized and bypasses to ext_ops.hdev_attach. So, we can factor out the fundamental part of snd_hda_codec_device_new() that is irrelevant with the card object and call it in hdac_hda_dev_probe(). Most of the legacy HD-audio codec can work without the card object, including suspend/resume. But this will be a more intensive surgery, and maybe not much worth for the corner case, so I already applied your patch as is. thanks, Takashi
