Re: 2.6.25-rc8-mm1 -- BUG: bad unlock balance detected!

["Miles Lane" <miles.lane@gmail.com>]

Thanks Frederik!  This patch seems to have done the trick.

         Miles

On Thu, Apr 3, 2008 at 5:58 AM, Frederik Deweerdt <deweerdt@free.fr> wrote:
> [Trimmed CC a bit, add Takashi Iwai]
>  Hi,
>
>
> On Wed, Apr 02, 2008 at 08:19:29AM -0400, Miles Lane wrote:
>  > [   48.765906] [ BUG: bad unlock balance detected! ]
>  > [   48.765912] -------------------------------------
>  > [   48.765918] pulseaudio/4277 is trying to release lock
>  > (&codec->spdif_mutex) at:
>  > [   48.765930] [<c03031b7>] mutex_unlock+0x8/0xa
>  > [   48.765945] but there are no more locks to release!
>  > [   48.765950]
>  > [   48.765952] other info that might help us debug this:
>  > [   48.765959] 2 locks held by pulseaudio/4277:
>  > [   48.765965]  #0:  (&pcm->open_mutex){--..}, at: [<f89f134b>]
>  > snd_pcm_open+0xc1/0x1ba [snd_pcm]
>  > [   48.766003]  #1:  (&chip->open_mutex){--..}, at: [<f8b4f13d>]
>  > azx_pcm_open+0x36/0x184 [snd_hda_intel]
>  > [   48.766057]
>  > [   48.766059] stack backtrace:
>  > [   48.766066] Pid: 4277, comm: pulseaudio Not tainted 2.6.25-rc8-mm1 #12
>  > [   48.766086]  [<c013afc6>] print_unlock_inbalance_bug+0xce/0xd8
>  > [   48.766107]  [<c0109e1c>] ? save_stack_trace+0x1d/0x3b
>  > [   48.766130]  [<c012f54e>] ? __kernel_text_address+0x1b/0x27
>  > [   48.766146]  [<c0104533>] ? dump_trace+0xcd/0xd9
>  > [   48.766160]  [<c0109d9e>] ? save_stack_address+0x0/0x2c
>  > [   48.766176]  [<c013b80a>] ? find_usage_backwards+0xa4/0xc3
>  > [   48.766193]  [<c013cfb5>] lock_release_non_nested+0x84/0x120
>  > [   48.766209]  [<c03031b7>] ? mutex_unlock+0x8/0xa
>  > [   48.766222]  [<c013d1bb>] lock_release+0x16a/0x199
>  > [   48.766238]  [<c0303137>] __mutex_unlock_slowpath+0xa9/0x121
>  > [   48.766252]  [<c03031b7>] mutex_unlock+0x8/0xa
>  > [   48.766263]  [<f8b4ffd8>] snd_hda_multi_out_analog_open+0xd3/0xef
>  > [snd_hda_intel]
>  The following patch should fix it. The buggy code comes from
>  git-alsa-tiwai.patch .
>
>  Regards,
>  Frederik
>
>
>  diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
>  index 689d177..a6be6e3 100644
>  --- a/sound/pci/hda/hda_codec.c
>  +++ b/sound/pci/hda/hda_codec.c
>  @@ -2665,8 +2665,8 @@ int snd_hda_multi_out_analog_open(struct hda_codec *codec,
>                         if (mout->spdif_maxbps < hinfo->maxbps)
>                                 hinfo->maxbps = mout->spdif_maxbps;
>                 }
>  +               mutex_unlock(&codec->spdif_mutex);
>         }
>  -       mutex_unlock(&codec->spdif_mutex);
>         return snd_pcm_hw_constraint_step(substream->runtime, 0,
>                                           SNDRV_PCM_HW_PARAM_CHANNELS, 2);
>   }
>