At Mon, 10 Sep 2012 23:00:39 +0800, Daniel J Blueman wrote:
On 10 September 2012 16:29, Takashi Iwai tiwai@suse.de wrote:
At Mon, 10 Sep 2012 09:46:43 +0200, Takashi Iwai wrote:
At Sun, 9 Sep 2012 13:02:16 +0800, Daniel J Blueman wrote:
With a non-specialised Cirrus HDA codec, it's readily possible to cause a kernel oops as root with 3.6-rc kernels [1].
patch_cirrus.c:
static int cs_init(struct hda_codec *codec) { struct cs_spec *spec = codec->spec;
/* init_verb sequence for C0/C1/C2 errata*/ snd_hda_sequence_write(codec, cs_errata_init_verbs); snd_hda_sequence_write(codec, cs_coef_init_verbs); if (spec->gpio_mask) { snd_hda_codec_write(codec, 0x01, 0, AC_VERB_SET_GPIO_MASK, spec->gpio_mask);Here, spec is NULL, so loading spec->gpio_mask causes a fatal pagefault at address 0x180 (ie the offset of gpio_mask in the struct). I was going to prepare a patch to guard for this, but since spec is expected in so many places, there is a likely a behavioural issue preventing a spec struct being generated.
Let me know for further testing and debug.
It's because of calling a leftover callback. The patch below should fix the issue. I'll queue it up to for-linus branch.
Oops, a wrong patch. The corrected one below.
[...]
Superb; this fixes the issue nicely.
Thanks Takashi!
OK, thanks for confirmation!
Takashi