The recently introduced coef_mutex for Realtek codec seems causing a deadlock when the relevant code is invoked from the power-off state; then the HD-audio core tries to power-up internally, and this kicks off the codec runtime PM code that tries to take the same coef_mutex.

In order to avoid the deadlock, do the temporary power up/down around the coef_mutex acquisition and release. This assures that the power-up sequence runs before the mutex, hence no re-entrance will happen.

Fixes: b837a9f5ab3b ("ALSA: hda: realtek: Fix race at concurrent COEF updates") Reported-and-tested-by: Julian Wollrath jwollrath@web.de Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220214132838.4db10fca@schienar Signed-off-by: Takashi Iwai tiwai@suse.de --- sound/pci/hda/patch_realtek.c | 39 +++++++++++++++++++++-------------- 1 file changed, 24 insertions(+), 15 deletions(-)

diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c index 9473fb76ff19..3a42457984e9 100644 --- a/sound/pci/hda/patch_realtek.c +++ b/sound/pci/hda/patch_realtek.c @@ -138,6 +138,22 @@ struct alc_spec { * COEF access helper functions */

+static void coef_mutex_lock(struct hda_codec *codec) +{ + struct alc_spec *spec = codec->spec; + + snd_hda_power_up_pm(codec); + mutex_lock(&spec->coef_mutex); +} + +static void coef_mutex_unlock(struct hda_codec *codec) +{ + struct alc_spec *spec = codec->spec; + + mutex_unlock(&spec->coef_mutex); + snd_hda_power_down_pm(codec); +} + static int __alc_read_coefex_idx(struct hda_codec *codec, hda_nid_t nid, unsigned int coef_idx) { @@ -151,12 +167,11 @@ static int __alc_read_coefex_idx(struct hda_codec *codec, hda_nid_t nid, static int alc_read_coefex_idx(struct hda_codec *codec, hda_nid_t nid, unsigned int coef_idx) { - struct alc_spec *spec = codec->spec; unsigned int val;

- mutex_lock(&spec->coef_mutex); + coef_mutex_lock(codec); val = __alc_read_coefex_idx(codec, nid, coef_idx); - mutex_unlock(&spec->coef_mutex); + coef_mutex_unlock(codec); return val; }

@@ -173,11 +188,9 @@ static void __alc_write_coefex_idx(struct hda_codec *codec, hda_nid_t nid, static void alc_write_coefex_idx(struct hda_codec *codec, hda_nid_t nid, unsigned int coef_idx, unsigned int coef_val) { - struct alc_spec *spec = codec->spec; - - mutex_lock(&spec->coef_mutex); + coef_mutex_lock(codec); __alc_write_coefex_idx(codec, nid, coef_idx, coef_val); - mutex_unlock(&spec->coef_mutex); + coef_mutex_unlock(codec); }

#define alc_write_coef_idx(codec, coef_idx, coef_val) \ @@ -198,11 +211,9 @@ static void alc_update_coefex_idx(struct hda_codec *codec, hda_nid_t nid, unsigned int coef_idx, unsigned int mask, unsigned int bits_set) { - struct alc_spec *spec = codec->spec; - - mutex_lock(&spec->coef_mutex); + coef_mutex_lock(codec); __alc_update_coefex_idx(codec, nid, coef_idx, mask, bits_set); - mutex_unlock(&spec->coef_mutex); + coef_mutex_unlock(codec); }

#define alc_update_coef_idx(codec, coef_idx, mask, bits_set) \ @@ -235,9 +246,7 @@ struct coef_fw { static void alc_process_coef_fw(struct hda_codec *codec, const struct coef_fw *fw) { - struct alc_spec *spec = codec->spec; - - mutex_lock(&spec->coef_mutex); + coef_mutex_lock(codec); for (; fw->nid; fw++) { if (fw->mask == (unsigned short)-1) __alc_write_coefex_idx(codec, fw->nid, fw->idx, fw->val); @@ -245,7 +254,7 @@ static void alc_process_coef_fw(struct hda_codec *codec, __alc_update_coefex_idx(codec, fw->nid, fw->idx, fw->mask, fw->val); } - mutex_unlock(&spec->coef_mutex); + coef_mutex_unlock(codec); }

/*