Re: Logitech USB headset not working in 3.6-rc3

[Daniel Mack]

This is a multi-part message in MIME format.On 29.08.2012 15:29, Takashi Iwai wrote:
> At Wed, 29 Aug 2012 13:26:25 +0200,
> Daniel Mack wrote:
>>
>> [1  <text/plain; ISO-8859-1 (7bit)>]
>> On 25.08.2012 14:17, Josh Boyer wrote:
>>> On Sat, Aug 25, 2012 at 02:13:58PM +0200, Daniel Mack wrote:
>>>> On 25.08.2012 14:07, Bruno Wolff III wrote:
>>>>> On Sat, Aug 25, 2012 at 14:02:51 +0200,
>>>>>    Daniel Mack <zonque@xxxxxxxxx> wrote:
>>>>>>
>>>>>> Can you revert commit e9ba389c5 ("ALSA: usb-audio: Fix
>>>>>> scheduling-while-atomic bug in PCM capture stream") and see if that
>>>>>
>>>>> I can try that, but it takes a long time to build a new kernel on my 
>>>>> old hardware.
>>>>>
>>>>>> helps? If not, can you summarize again which kernels still work for you
>>>>>> and which don't?
>>>>>
>>>>> The latest kernel that works is 3.6.0-0.rc2.git1.2.fc18. The earliest that 
>>>>> doesn't work is 3.6.0-0.rc2.git2.1.fc18.
>>>>>
>>>>
>>>> The report you sent doesn't look like it could be caused by e9ba389c5.
>>>> It fixes a kernel Ooops. But as it is the only relevant patch in that
>>>> area, it would be interesting if reverting it fixes anything.
>>>
>>> Yep, agreed.  If this revert kernel doesn't work, we're likely down to a
>>> git bisect, Bruno.
>>>
>>>> Btw - thanks a lot for testing -rc kernels, much appreciated!
>>>
>>> Indeed!
>>
>> Could you please try this patch on top of Takashi's? Thanks again!
>>
>>
>> Daniel
>>
>> [2 0001-ALSA-snd-usb-Fix-URB-cancellation-at-stream-start.patch <text/x-patch (7bit)>]
>> >From 6617bb2463ae3fad21390b59cc2a71f96b9e9ca8 Mon Sep 17 00:00:00 2001
>> From: Daniel Mack <zonque@xxxxxxxxx>
>> Date: Wed, 29 Aug 2012 13:17:05 +0200
>> Subject: [PATCH] ALSA: snd-usb: Fix URB cancellation at stream start
>>
>> Commit e9ba389c5 ("ALSA: usb-audio: Fix scheduling-while-atomic bug in
>> PCM capture stream") fixed a scheduling-while-atomic bug that happened
>> when snd_usb_endpoint_start was called from the trigger callback, which
>> is an atmic context. However, the patch breaks the idea of the endpoints
>> reference counting, which is the reason why the driver has been
>> refactored lately.
>>
>> Revert that commit and let snd_usb_endpoint_start() take care of the URB
>> cancellation again. As this function is called from both atomic and
>> non-atomic context, add a flag to denote whether the function may sleep.
>>
>> Signed-off-by: Daniel Mack <zonque@xxxxxxxxx>
>> Cc: stable@xxxxxxxxxx [3.5+]
>> ---
>>  sound/usb/endpoint.c | 10 ++++++++--
>>  sound/usb/endpoint.h |  2 +-
>>  sound/usb/pcm.c      | 13 +++++--------
>>  3 files changed, 14 insertions(+), 11 deletions(-)
>>
>> diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
>> index c411812..678456c 100644
>> --- a/sound/usb/endpoint.c
>> +++ b/sound/usb/endpoint.c
>> @@ -799,7 +799,9 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
>>  /**
>>   * snd_usb_endpoint_start: start an snd_usb_endpoint
>>   *
>> - * @ep: the endpoint to start
>> + * @ep:		the endpoint to start
>> + * @can_sleep:	flag indicating whether the operation is executed in
>> + * 		non-atomic context
>>   *
>>   * A call to this function will increment the use count of the endpoint.
>>   * In case it is not already running, the URBs for this endpoint will be
>> @@ -809,7 +811,7 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
>>   *
>>   * Returns an error if the URB submission failed, 0 in all other cases.
>>   */
>> -int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
>> +int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep)
>>  {
>>  	int err;
>>  	unsigned int i;
>> @@ -821,6 +823,10 @@ int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
>>  	if (++ep->use_count != 1)
>>  		return 0;
>>  
>> +	/* just to be sure */
>> +	deactivate_urbs(ep, 0, can_sleep);
>> +	wait_clear_urbs(ep);
> 
> It'd be safer to protect the call of wait_clear_urbs() when
> can_sleep=0.

Right. New patch attached.