| From 305a0ade180981686eec1f92aa6252a7c6ebb1cf Mon Sep 17 00:00:00 2001 |
| From: Takashi Iwai <tiwai@suse.de> |
| Date: Wed, 30 Jan 2019 17:46:03 +0100 |
| Subject: ALSA: hda - Serialize codec registrations |
| |
| From: Takashi Iwai <tiwai@suse.de> |
| |
| commit 305a0ade180981686eec1f92aa6252a7c6ebb1cf upstream. |
| |
| In the current code, the codec registration may happen both at the |
| codec bind time and the end of the controller probe time. In a rare |
| occasion, they race with each other, leading to Oops due to the still |
| uninitialized card device. |
| |
| This patch introduces a simple flag to prevent the codec registration |
| at the codec bind time as long as the controller probe is going on. |
| The controller probe invokes snd_card_register() that does the whole |
| registration task, and we don't need to register each piece |
| beforehand. |
| |
| Cc: <stable@vger.kernel.org> |
| Signed-off-by: Takashi Iwai <tiwai@suse.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| sound/pci/hda/hda_bind.c | 3 ++- |
| sound/pci/hda/hda_codec.h | 1 + |
| sound/pci/hda/hda_intel.c | 2 ++ |
| 3 files changed, 5 insertions(+), 1 deletion(-) |
| |
| --- a/sound/pci/hda/hda_bind.c |
| +++ b/sound/pci/hda/hda_bind.c |
| @@ -109,7 +109,8 @@ static int hda_codec_driver_probe(struct |
| err = snd_hda_codec_build_controls(codec); |
| if (err < 0) |
| goto error_module; |
| - if (codec->card->registered) { |
| + /* only register after the bus probe finished; otherwise it's racy */ |
| + if (!codec->bus->bus_probing && codec->card->registered) { |
| err = snd_card_register(codec->card); |
| if (err < 0) |
| goto error_module; |
| --- a/sound/pci/hda/hda_codec.h |
| +++ b/sound/pci/hda/hda_codec.h |
| @@ -68,6 +68,7 @@ struct hda_bus { |
| unsigned int response_reset:1; /* controller was reset */ |
| unsigned int in_reset:1; /* during reset operation */ |
| unsigned int no_response_fallback:1; /* don't fallback at RIRB error */ |
| + unsigned int bus_probing :1; /* during probing process */ |
| |
| int primary_dig_out_type; /* primary digital out PCM type */ |
| unsigned int mixer_assigned; /* codec addr for mixer name */ |
| --- a/sound/pci/hda/hda_intel.c |
| +++ b/sound/pci/hda/hda_intel.c |
| @@ -2100,6 +2100,7 @@ static int azx_probe_continue(struct azx |
| int val; |
| int err; |
| |
| + to_hda_bus(bus)->bus_probing = 1; |
| hda->probe_continued = 1; |
| |
| /* Request display power well for the HDA controller or codec. For |
| @@ -2200,6 +2201,7 @@ i915_power_fail: |
| if (err < 0) |
| hda->init_failed = 1; |
| complete_all(&hda->probe_wait); |
| + to_hda_bus(bus)->bus_probing = 0; |
| return err; |
| } |
| |
