6.6-stable review patch. If anyone has any objections, please let me know.
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From: Edmund Raile edmund.raile@protonmail.com
commit 6ccf9984d6be3c2f804087b736db05c2ec42664b upstream.
prepare resolution of AB/BA deadlock competition for substream lock: restore workqueue previously used for process context:
revert commit b5b519965c4c ("ALSA: firewire-lib: obsolete workqueue for period update")
Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/kwryofzdmjvzkuw6j3clftsxmoolynljztxqwg76hzeo4simnl... Signed-off-by: Edmund Raile edmund.raile@protonmail.com Reviewed-by: Takashi Sakamoto o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai tiwai@suse.de Link: https://patch.msgid.link/20240730195318.869840-2-edmund.raile@protonmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- sound/firewire/amdtp-stream.c | 15 +++++++++++++++ sound/firewire/amdtp-stream.h | 1 + 2 files changed, 16 insertions(+)
--- a/sound/firewire/amdtp-stream.c +++ b/sound/firewire/amdtp-stream.c @@ -77,6 +77,8 @@ // overrun. Actual device can skip more, then this module stops the packet streaming. #define IR_JUMBO_PAYLOAD_MAX_SKIP_CYCLES 5
+static void pcm_period_work(struct work_struct *work); + /** * amdtp_stream_init - initialize an AMDTP stream structure * @s: the AMDTP stream to initialize @@ -105,6 +107,7 @@ int amdtp_stream_init(struct amdtp_strea s->flags = flags; s->context = ERR_PTR(-1); mutex_init(&s->mutex); + INIT_WORK(&s->period_work, pcm_period_work); s->packet_index = 0;
init_waitqueue_head(&s->ready_wait); @@ -347,6 +350,7 @@ EXPORT_SYMBOL(amdtp_stream_get_max_paylo */ void amdtp_stream_pcm_prepare(struct amdtp_stream *s) { + cancel_work_sync(&s->period_work); s->pcm_buffer_pointer = 0; s->pcm_period_pointer = 0; } @@ -624,6 +628,16 @@ static void update_pcm_pointers(struct a } }
+static void pcm_period_work(struct work_struct *work) +{ + struct amdtp_stream *s = container_of(work, struct amdtp_stream, + period_work); + struct snd_pcm_substream *pcm = READ_ONCE(s->pcm); + + if (pcm) + snd_pcm_period_elapsed(pcm); +} + static int queue_packet(struct amdtp_stream *s, struct fw_iso_packet *params, bool sched_irq) { @@ -1912,6 +1926,7 @@ static void amdtp_stream_stop(struct amd return; }
+ cancel_work_sync(&s->period_work); fw_iso_context_stop(s->context); fw_iso_context_destroy(s->context); s->context = ERR_PTR(-1); --- a/sound/firewire/amdtp-stream.h +++ b/sound/firewire/amdtp-stream.h @@ -191,6 +191,7 @@ struct amdtp_stream {
/* For a PCM substream processing. */ struct snd_pcm_substream *pcm; + struct work_struct period_work; snd_pcm_uframes_t pcm_buffer_pointer; unsigned int pcm_period_pointer; unsigned int pcm_frame_multiplier;