Re: [PATCH] ALSA: hda - Fix race between PM ops and HDA init/probe

[Takashi Iwai <tiwai@suse.de>]

On Tue, 28 Jul 2015 22:29:56 +0200,
U. Artie Eoff wrote:
> 
> PM ops could be triggered before HDA is done initializing
> and cause PM to set HDA controller to D3Hot.  This can result
> in "CORB reset timeout#2, CORBRP = 65535" and "no codecs
> initialized".  Additionally, PM ops can be triggered before
> azx_probe_continue finishes (async probe).  This can result
> in a NULL deref kernel crash.
> 
> To fix this, avoid PM ops if !chip->running.
> 
> Signed-off-by: U. Artie Eoff <ullysses.a.eoff@intel.com>
> ---
>  sound/pci/hda/hda_intel.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
> index 735bdcb04ce8..c38c68f57938 100644
> --- a/sound/pci/hda/hda_intel.c
> +++ b/sound/pci/hda/hda_intel.c
> @@ -867,7 +867,7 @@ static int azx_suspend(struct device *dev)
>  
>  	chip = card->private_data;
>  	hda = container_of(chip, struct hda_intel, chip);
> -	if (chip->disabled || hda->init_failed)
> +	if (chip->disabled || hda->init_failed || !chip->running)

This is superfluous, as azx_runtime_idle() returns -EBUSY.

>  		return 0;
>  
>  	bus = azx_bus(chip);
> @@ -902,7 +902,7 @@ static int azx_resume(struct device *dev)
>  
>  	chip = card->private_data;
>  	hda = container_of(chip, struct hda_intel, chip);
> -	if (chip->disabled || hda->init_failed)
> +	if (chip->disabled || hda->init_failed || !chip->running)

Ditto.


Takashi

>  		return 0;
>  
>  	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
> @@ -1027,7 +1027,7 @@ static int azx_runtime_idle(struct device *dev)
>  		return 0;
>  
>  	if (!power_save_controller || !azx_has_pm_runtime(chip) ||
> -	    azx_bus(chip)->codec_powered)
> +	    azx_bus(chip)->codec_powered || !chip->running)
>  		return -EBUSY;
>  
>  	return 0;
> -- 
> 2.1.0
>