azx_codec_configure() loops over the codecs found on the given controller via a linked list. The code used to work in the past, but in the current version, this may lead to an endless loop when a codec binding returns an error.

The culprit is that the snd_hda_codec_configure() unregisters the device upon error, and this eventually deletes the given codec object from the bus. Since the list is initialized via list_del_init(), the next object points to the same device itself. This behavior change was introduced at splitting the HD-audio code code, and forgotten to adapt it here.

For fixing this bug, just use a *_safe() version of list iteration.

Fixes: d068ebc25e6e ("ALSA: hda - Move some codes up to hdac_bus struct") Reported-by: Daniel Vetter daniel.vetter@ffwll.ch Cc: stable@vger.kernel.org Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/pci/hda/hda_codec.h | 2 ++ sound/pci/hda/hda_controller.c | 8 ++++++-- 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h index d6fb2d5d01a7..60ce1cfc300f 100644 --- a/sound/pci/hda/hda_codec.h +++ b/sound/pci/hda/hda_codec.h @@ -295,6 +295,8 @@ struct hda_codec {

#define list_for_each_codec(c, bus) \ list_for_each_entry(c, &(bus)->core.codec_list, core.list) +#define list_for_each_codec_safe(c, n, bus) \ + list_for_each_entry_safe(c, n, &(bus)->core.codec_list, core.list)

/* snd_hda_codec_read/write optional flags */ #define HDA_RW_NO_RESPONSE_FALLBACK (1 << 0) diff --git a/sound/pci/hda/hda_controller.c b/sound/pci/hda/hda_controller.c index 3715a5725613..1c60beb5b70a 100644 --- a/sound/pci/hda/hda_controller.c +++ b/sound/pci/hda/hda_controller.c @@ -1337,8 +1337,12 @@ EXPORT_SYMBOL_GPL(azx_probe_codecs); /* configure each codec instance */ int azx_codec_configure(struct azx *chip) { - struct hda_codec *codec; - list_for_each_codec(codec, &chip->bus) { + struct hda_codec *codec, *next; + + /* use _safe version here since snd_hda_codec_configure() deregisters + * the device upon error and deletes itself from the bus list. + */ + list_for_each_codec_safe(codec, next, &chip->bus) { snd_hda_codec_configure(codec); } return 0;

We used a on-demand i915 component binding for IvyBridge and SandyBridge HDMI codecs, but it has a potential problem of the nested module loading. For avoiding that situation, assure the i915 binding happening at the controller driver level for PCH controller devices, where the initialization is performed in a detached work, instead of calling from the codec driver probe.

Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/pci/hda/hda_intel.c | 4 ++-- sound/pci/hda/patch_hdmi.c | 17 +++++------------ 2 files changed, 7 insertions(+), 14 deletions(-)

diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 01eb1dc7b5b3..2db3203090ed 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -294,11 +294,11 @@ enum {

/* PCH up to IVB; no runtime PM */ #define AZX_DCAPS_INTEL_PCH_NOPM \ - (AZX_DCAPS_INTEL_PCH_BASE) + (AZX_DCAPS_INTEL_PCH_BASE | AZX_DCAPS_I915_POWERWELL)

/* PCH for HSW/BDW; with runtime PM */ #define AZX_DCAPS_INTEL_PCH \ - (AZX_DCAPS_INTEL_PCH_BASE | AZX_DCAPS_PM_RUNTIME) + (AZX_DCAPS_INTEL_PCH_NOPM | AZX_DCAPS_PM_RUNTIME)

/* HSW HDMI */ #define AZX_DCAPS_INTEL_HASWELL \ diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c index 90e4ff87445e..feed8e8de2af 100644 --- a/sound/pci/hda/patch_hdmi.c +++ b/sound/pci/hda/patch_hdmi.c @@ -174,7 +174,6 @@ struct hdmi_spec { /* i915/powerwell (Haswell+/Valleyview+) specific */ bool use_acomp_notifier; /* use i915 eld_notify callback for hotplug */ struct i915_audio_component_audio_ops i915_audio_ops; - bool i915_bound; /* was i915 bound in this driver? */

struct hdac_chmap chmap; hda_nid_t vendor_nid; @@ -2234,8 +2233,6 @@ static void generic_spec_free(struct hda_codec *codec) struct hdmi_spec *spec = codec->spec;

if (spec) { - if (spec->i915_bound) - snd_hdac_i915_exit(&codec->bus->core); hdmi_array_free(spec); kfree(spec); codec->spec = NULL; @@ -2607,21 +2604,17 @@ static int patch_i915_cpt_hdmi(struct hda_codec *codec) struct hdmi_spec *spec; int err;

- /* no i915 component should have been bound before this */ - if (WARN_ON(codec->bus->core.audio_component)) - return -EBUSY; + /* requires i915 binding */ + if (!codec->bus->core.audio_component) { + codec_info(codec, "No i915 binding for Intel HDMI/DP codec\n"); + return -ENODEV; + }

err = alloc_generic_hdmi(codec); if (err < 0) return err; spec = codec->spec;

- /* Try to bind with i915 now */ - err = snd_hdac_i915_init(&codec->bus->core); - if (err < 0) - goto error; - spec->i915_bound = true; - err = hdmi_parse_codec(codec); if (err < 0) goto error;

No functional change, just a slight reduction of lines.

Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/pci/hda/patch_hdmi.c | 87 ++++++++++++++++++---------------------------- 1 file changed, 34 insertions(+), 53 deletions(-)

diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c index feed8e8de2af..8704ea43381e 100644 --- a/sound/pci/hda/patch_hdmi.c +++ b/sound/pci/hda/patch_hdmi.c @@ -2503,19 +2503,41 @@ static void i915_pin_cvt_fixup(struct hda_codec *codec, } }

-/* Intel Haswell and onwards; audio component with eld notifier */ -static int intel_hsw_common_init(struct hda_codec *codec, hda_nid_t vendor_nid) +/* precondition and allocation for Intel codecs */ +static int alloc_intel_hdmi(struct hda_codec *codec) { - struct hdmi_spec *spec; - int err; - - /* HSW+ requires i915 binding */ + /* requires i915 binding */ if (!codec->bus->core.audio_component) { codec_info(codec, "No i915 binding for Intel HDMI/DP codec\n"); return -ENODEV; }

- err = alloc_generic_hdmi(codec); + return alloc_generic_hdmi(codec); +} + +/* parse and post-process for Intel codecs */ +static int parse_intel_hdmi(struct hda_codec *codec) +{ + int err; + + err = hdmi_parse_codec(codec); + if (err < 0) { + generic_spec_free(codec); + return err; + } + + generic_hdmi_init_per_pins(codec); + register_i915_notifier(codec); + return 0; +} + +/* Intel Haswell and onwards; audio component with eld notifier */ +static int intel_hsw_common_init(struct hda_codec *codec, hda_nid_t vendor_nid) +{ + struct hdmi_spec *spec; + int err; + + err = alloc_intel_hdmi(codec); if (err < 0) return err; spec = codec->spec; @@ -2539,15 +2561,7 @@ static int intel_hsw_common_init(struct hda_codec *codec, hda_nid_t vendor_nid) spec->ops.setup_stream = i915_hsw_setup_stream; spec->ops.pin_cvt_fixup = i915_pin_cvt_fixup;

- err = hdmi_parse_codec(codec); - if (err < 0) { - generic_spec_free(codec); - return err; - } - - generic_hdmi_init_per_pins(codec); - register_i915_notifier(codec); - return 0; + return parse_intel_hdmi(codec); }

static int patch_i915_hsw_hdmi(struct hda_codec *codec) @@ -2566,13 +2580,7 @@ static int patch_i915_byt_hdmi(struct hda_codec *codec) struct hdmi_spec *spec; int err;

- /* requires i915 binding */ - if (!codec->bus->core.audio_component) { - codec_info(codec, "No i915 binding for Intel HDMI/DP codec\n"); - return -ENODEV; - } - - err = alloc_generic_hdmi(codec); + err = alloc_intel_hdmi(codec); if (err < 0) return err; spec = codec->spec; @@ -2587,45 +2595,18 @@ static int patch_i915_byt_hdmi(struct hda_codec *codec)

spec->ops.pin_cvt_fixup = i915_pin_cvt_fixup;

- err = hdmi_parse_codec(codec); - if (err < 0) { - generic_spec_free(codec); - return err; - } - - generic_hdmi_init_per_pins(codec); - register_i915_notifier(codec); - return 0; + return parse_intel_hdmi(codec); }

/* Intel IronLake, SandyBridge and IvyBridge; with eld notifier */ static int patch_i915_cpt_hdmi(struct hda_codec *codec) { - struct hdmi_spec *spec; int err;

- /* requires i915 binding */ - if (!codec->bus->core.audio_component) { - codec_info(codec, "No i915 binding for Intel HDMI/DP codec\n"); - return -ENODEV; - } - - err = alloc_generic_hdmi(codec); + err = alloc_intel_hdmi(codec); if (err < 0) return err; - spec = codec->spec; - - err = hdmi_parse_codec(codec); - if (err < 0) - goto error; - - generic_hdmi_init_per_pins(codec); - register_i915_notifier(codec); - return 0; - - error: - generic_spec_free(codec); - return err; + return parse_intel_hdmi(codec); }

/*