On Tue, 13 Oct 2020 17:26:28 +0200, Kai Vehmanen wrote: > > A race exists between closing a PCM and update of ELD data. In > hdmi_pcm_close(), hinfo->nid value is modified without taking > spec->pcm_lock. If this happens concurrently while processing an ELD > update in hdmi_pcm_setup_pin(), converter assignment may be done > incorrectly. > > This bug was found by hitting a WARN_ON in snd_hda_spdif_ctls_assign() > in a HDMI receiver connection stress test: > > [2739.684569] WARNING: CPU: 5 PID: 2090 at sound/pci/hda/patch_hdmi.c:1898 check_non_pcm_per_cvt+0x41/0x50 [snd_hda_codec_hdmi] > ... > [2739.684707] Call Trace: > [2739.684720] update_eld+0x121/0x5a0 [snd_hda_codec_hdmi] > [2739.684736] hdmi_present_sense+0x21e/0x3b0 [snd_hda_codec_hdmi] > [2739.684750] check_presence_and_report+0x81/0xd0 [snd_hda_codec_hdmi] > [2739.684842] intel_audio_codec_enable+0x122/0x190 [i915] > > Fixes: 42b2987079ec ("ALSA: hda - hdmi playback without monitor in dynamic pcm bind mode") > Signed-off-by: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx> Applied now. Thanks. Takashi