[alsa-devel] [PATCH 0/2] PCM OSS fixes

[Lars-Peter Clausen]

On 01/08/2018 04:05 PM, Takashi Iwai wrote:
> On Mon, 08 Jan 2018 15:58:47 +0100,
> Lars-Peter Clausen wrote:
>>
>> On 01/08/2018 03:25 PM, Takashi Iwai wrote:
>>> Hi,
>>>
>>> this contains two fixes for PCM OSS bugs that have been triggered by
>>> syzbot.  These are simple and straightforward, and I'm going to queue
>>> for 4.15-rc8.
>>
>> I tried to reproduce the issue as well with the reproducer generated by
>> syzbot. But what syzbot reported was that the CPU didn't sleep for 140
>> seconds. But with a long write() we'll go to sleep in between frames. So
>> when I tried the lockup detector never triggered.
>>
>> Were you able to reproduce the same CPU lockup as syzbot?
> 
> Yes, I could reproduce RCU stalls with two reproducers
> (001a113ece5c2b600d05620b097a at google.com and
>  001a1147e1988b160a05620552eb at google.com)
> 
> The patches seem curing them, so far, in combination with other
> patches in for-linus branch of sound.git tree.
> 

Hm, interesting. Are you using aloop for the backend or real hardware?