4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Takashi Iwai <tiwai@xxxxxxx> commit 2deaeaf102d692cb6f764123b1df7aa118a8e97c upstream. The standard PCM chmap helper callbacks treat the NULL info->chmap as a fatal error and spews the kernel warning with stack trace when CONFIG_SND_DEBUG is on. This was OK, originally it was supposed to be always static and non-NULL. But, as the recent addition of Intel LPE audio driver shows, the chmap content may vary dynamically, and it can be even NULL when disconnected. The user still sees the kernel warning unnecessarily. For clearing such a confusion, this patch simply removes the snd_BUG_ON() in each place, just returns an error without warning. Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- sound/core/pcm_lib.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -2491,7 +2491,7 @@ static int pcm_chmap_ctl_get(struct snd_ struct snd_pcm_substream *substream; const struct snd_pcm_chmap_elem *map; - if (snd_BUG_ON(!info->chmap)) + if (!info->chmap) return -EINVAL; substream = snd_pcm_chmap_substream(info, idx); if (!substream) @@ -2523,7 +2523,7 @@ static int pcm_chmap_ctl_tlv(struct snd_ unsigned int __user *dst; int c, count = 0; - if (snd_BUG_ON(!info->chmap)) + if (!info->chmap) return -EINVAL; if (size < 8) return -ENOMEM;