sound/pci/hda/hda_codec.c:3433 snd_hda_codec_write_cache() error: we previously assumed 'c' could be null (see line 3430)

sound/pci/hda/hda_codec.c:3433 snd_hda_codec_write_cache() error: we previously assumed 'c' could be null (see line 3430)

[Fengguang Wu]

Hi Takashi,

FYI, there are new smatch warnings show up in

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-unstable.git master
head:   02e5aa7b459f69538d4ec88658d064816a7692d6
commit: 95836563e7f636fc57732f5e687ca2f170eb674f ALSA: hda - Introduce cache & flush cmd / amp writes
date:   33 hours ago

sound/pci/hda/hda_codec.c:3433 snd_hda_codec_write_cache() error: we previously assumed 'c' could be null (see line 3430)

vim +/c +3433 sound/pci/hda/hda_codec.c

aa2936f5 Takashi Iwai 2009-05-26  3424  	/* parm may contain the verb stuff for get/set amp */
aa2936f5 Takashi Iwai 2009-05-26  3425  	verb = verb | (parm >> 8);
aa2936f5 Takashi Iwai 2009-05-26  3426  	parm &= 0xff;
aa2936f5 Takashi Iwai 2009-05-26  3427  	key = build_cmd_cache_key(nid, verb);
aa2936f5 Takashi Iwai 2009-05-26  3428  	mutex_lock(&codec->bus->cmd_mutex);
aa2936f5 Takashi Iwai 2009-05-26  3429  	c = get_alloc_hash(&codec->cmd_cache, key);
aa2936f5 Takashi Iwai 2009-05-26 @3430  	if (c)
aa2936f5 Takashi Iwai 2009-05-26  3431  		c->val = parm;
95836563 Takashi Iwai 2012-12-13  3432  	if (codec->cached_write)
95836563 Takashi Iwai 2012-12-13 @3433  		c->dirty = 1;
aa2936f5 Takashi Iwai 2009-05-26  3434  	mutex_unlock(&codec->bus->cmd_mutex);
aa2936f5 Takashi Iwai 2009-05-26  3435  	return 0;
b3ac5636 Takashi Iwai 2007-08-10  3436  }

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0-DAY kernel build testing backend         Open Source Technology Center
Fengguang Wu, Yuanhan Liu                              Intel Corporation