Thanks for the reply :)
On 2018/10/3 23:54, Takashi Iwai wrote:
On Wed, 03 Oct 2018 14:50:25 +0200,
Jia-Ju Bai wrote:
CPU0:
snd_trident_hw_free
snd_trident_free_voice
line 3870: spin_lock_irqsave()
line 3881: voice->substream = NULL; [WRITE]
CPU1:
snd_trident_interrupt
line 3798: snd_pcm_period_elapsed(voice->substream); [READ]
As for voice->substream, the WRITE operation in CPU0 is performed
with holding a spinlock, but the READ operation in CPU1 is performed
without holding this spinlock, so there may exist a data race.
Thanks for the report.
The actual crash must be very unlikely, almost 0%, though.
snd_trident_hw_free() is called always after the PCM stream gets
stopped via trigger callback, i.e. at the moment, there is no
corresponding interrupt is generated for that voice entry.
How about the case that playback and capture are performed concurrently?
Namely, snd_trident_hw_free() is called for playback, and the interrupt
is generated for capture.
And the hardware is very old, I bet only a handful people still using
in the whole world :)
I have this hardware, so I am the one of these handful people ;)
Best wishes,
Jia-Ju Bai
