[alsa-devel] oops during boot with CONFIG_SND_DYNAMIC_MINORS not set

[Takashi Iwai]

At Fri, 23 Aug 2013 00:56:01 +0300,
Stratos Karafotis wrote:
> 
> On 08/23/2013 12:23 AM, Takashi Iwai wrote:
> > At Thu, 22 Aug 2013 19:03:44 +0300,
> > Stratos Karafotis wrote:
> >>
> >> On 08/22/2013 10:59 AM, Takashi Iwai wrote:
> >>> At Thu, 22 Aug 2013 00:42:41 +0300,
> >>> Stratos Karafotis wrote:
> >>>>
> >>>> Hi,
> >>>>
> >>>> I get the following oops during boot when build with CONFIG_SND_DYNAMIC_MINORS
> >>>> not set (3.11-rc6).
> >>>> The issue is vanished building the kernel with CONFIG_SND_DYNAMIC_MINORS=y
> >>>> as suggested in printk message.
> >>>>
> >>>> Regards,
> >>>> Stratos
> >>>>
> >>>>
> >>>
> >>> Could you check the patch below?
> >>> Thanks!
> >>>
> >>>
> >>> Takashi
> >>>
> >>> ---
> >>> From: Takashi Iwai <tiwai at suse.de>
> >>> Subject: [PATCH] ALSA: hda - Fix NULL dereference with CONFIG_SND_DYNAMIC_MINORS=n
> >>>
> >>> Without the dynamic minor assignment, HDMI codec may have less PCM
> >>> instances than the number of pins, which eventually leads to Oops.
> >>>
> >>> Reported-by: Stratos Karafotis <stratosk at semaphore.gr>
> >>> Cc: <stable at vger.kernel.org>
> >>> Signed-off-by: Takashi Iwai <tiwai at suse.de>
> >>> ---
> >>>    sound/pci/hda/patch_hdmi.c | 3 +++
> >>>    1 file changed, 3 insertions(+)
> >>>
> >>> diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
> >>> index 030ca86..e2cb92b 100644
> >>> --- a/sound/pci/hda/patch_hdmi.c
> >>> +++ b/sound/pci/hda/patch_hdmi.c
> >>> @@ -1781,6 +1781,9 @@ static int generic_hdmi_build_controls(struct hda_codec *codec)
> >>>    		struct snd_pcm_chmap *chmap;
> >>>    		struct snd_kcontrol *kctl;
> >>>    		int i;
> >>> +
> >>> +		if (pin_idx >= codec->num_pcms)
> >>> +			break;
> >>>    		err = snd_pcm_add_chmap_ctls(codec->pcm_info[pin_idx].pcm,
> >>>    					     SNDRV_PCM_STREAM_PLAYBACK,
> >>>    					     NULL, 0, pin_idx, &chmap);
> >>>
> >>
> >> Hi,
> >>
> >> Unfortunately, still the same problem after applying your patch.
> > 
> > Bah, it's a wrong one.  The patch below should work better.
> > Sorry for inconvenience.
> 
> No problem! :)
> 
> Yes, no more oops with the latest patch.
> Tested with CONFIG_SND_DYNAMIC_MINORS=y and n.
> 
> There is an error -16 now (please see below), but I guess it's normal(?)

Yes, it's the expected behavior.
Thanks for quick tests!


Takashi

> Thanks,
> Stratos
> 
> 
> [   16.392453] ALSA sound/pci/hda/hda_codec.c:4506 Too many HDMI devices
> [   16.392457] ALSA sound/pci/hda/hda_codec.c:4508 Consider building the kernel with CONFIG_SND_DYNAMIC_MINORS=y
> [   16.392460] ALSA sound/pci/hda/hda_codec.c:4506 Too many HDMI devices
> [   16.392461] ALSA sound/pci/hda/hda_codec.c:4508 Consider building the kernel with CONFIG_SND_DYNAMIC_MINORS=y
> [   16.409640] ALSA sound/core/control.c:349 control 0:0:0:HDMI/DP Jack:0 is already present
> [   16.410627] hda_codec: cannot build controls for #3 (error -16)
> [   16.411683] input: HDA NVidia HDMI/DP as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input15
> [   16.411844] input: HDA NVidia HDMI/DP,pcm=7 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input16
> [   16.411986] input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input17
> [   19.682495] EXT4-fs (sda2): mounted filesystem with ordered data mode. Opts: (null)
> [   21.367420] FAT-fs (sda1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
> [   21.420191] EXT4-fs (dm-2): mounted filesystem with ordered data mode. Opts: (null)
> [   21.847085] type=1305 audit(1377207061.920:3): audit_pid=534 old=0 auid=4294967295 ses=4294967295
>  res=1
> [   22.164707] alsactl[549]: segfault at 1 ip 00007f6c8ad58a7d sp 00007fff19912de0 error 4 in libc-2.17.so[7f6c8ad10000+1b6000]
>