Re: next-0519 on thinkpad x60: sound related? window manager crash

From: Alex Xu (Hello71)
Date: Thu Jun 11 2020 - 10:56:34 EST


Excerpts from Takashi Iwai's message of June 9, 2020 11:12 am:
> On Tue, 09 Jun 2020 13:47:33 +0200,
> Christoph Hellwig wrote:
>>
>> Alex, can you try this patch?
>
> Also could you check whether just papering over the memset() call
> alone avoids the crash like below? For PulseAudio and dmix/dsnoop,
> it's the only code path that accesses the vmapped buffer, I believe.
>
> If this works more or less, I'll cook a more comprehensive fix.
>
>
> thanks,
>
> Takashi
>
> --- a/sound/core/pcm_native.c
> +++ b/sound/core/pcm_native.c
> @@ -754,9 +754,11 @@ static int snd_pcm_hw_params(struct snd_pcm_substream *substream,
> while (runtime->boundary * 2 <= LONG_MAX - runtime->buffer_size)
> runtime->boundary *= 2;
>
> +#if 0
> /* clear the buffer for avoiding possible kernel info leaks */
> if (runtime->dma_area && !substream->ops->copy_user)
> memset(runtime->dma_area, 0, runtime->dma_bytes);
> +#endif
>
> snd_pcm_timer_resolution_change(substream);
> snd_pcm_set_state(substream, SNDRV_PCM_STATE_SETUP);
>

Sorry, this patch doesn't work for me with SME off using abfbb29297c2.
David's newest submitted patch works for me, which I already replied to
separately.

Thanks,
Alex.