Hi,
Thank you for looking into it so quickly.
Dne četrtek, 08. marec 2018 ob 02:21:02 CET je Kuninori Morimoto napisal(a):
Hi Jernej
Thank you for your hard work
I found the issue. Commit be7ee5f32a9a ("ASoC: soc-generic-dmaengine-pcm:
replace platform to component") changes struct dmaengine_pcm: struct dmaengine_pcm {
struct dma_chan *chan[SNDRV_PCM_STREAM_LAST + 1]; const struct snd_dmaengine_pcm_config *config;
- struct snd_soc_platform platform;
struct snd_soc_component component;
unsigned int flags;
};
In snd_dmaengine_pcm_register(): ret = snd_soc_add_component(dev, &pcm->component,
&dmaengine_pcm_component, NULL, 0);And now, sun4i-codec first time returns -EPROBE_DEFER since driver for analog part is not yet loaded. Because of that, all components get destroyed.
snd_dmaengine_pcm_unregister() calls snd_soc_unregister_component() and that one calls __snd_soc_unregister_component() multiple times (until it fails).
Issue is that __snd_soc_unregister_component() uses kfree() on component pointer and that naturally can't succed since component was never kmalloc'ed since it is a part of a bigger structure - struct dmaengine_pcm.
What would be the best fix? Changing struct dmaengine_pcm to have pointer to a component, so it can be freed?
Ahh.. indeed. Good catch ! How about to add such flag ? This is just idea. No tested, No compiled, but can help you ?
One note here is that reusing "registered_as_component" flag is not good idea, because it will be removed when platform/codec were removed
diff --git a/include/sound/soc.h b/include/sound/soc.h index 1a73232..b9b1b4c 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -853,6 +853,7 @@ struct snd_soc_component { unsigned int ignore_pmdown_time:1; /* pmdown_time is ignored at stop */ unsigned int registered_as_component:1; unsigned int suspended:1; /* is in suspend PM state */
unsigned int alloced_component:1;
struct list_head list; struct list_head card_aux_list; /* for auxiliary bound components */
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index c0edac8..0e33bcf 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -3492,6 +3492,7 @@ int snd_soc_register_component(struct device *dev, if (!component) return -ENOMEM;
- component->alloced_component = 1; return snd_soc_add_component(dev, component, component_driver, dai_drv, num_dai);
} @@ -3523,7 +3524,9 @@ static int __snd_soc_unregister_component(struct device *dev)
if (found) { snd_soc_component_cleanup(component);
kfree(component);
if (component->alloced_component)kfree(component);}
return found;
I tested this patch and there is no crash anymore. If you will send it as a fix, you can add:
Reported-by: Jernej Skrabec jernej.skrabec@siol.net Tested-by: Jernej Skrabec jernej.skrabec@siol.net
Best regards, Jernej