This is a note to let you know that I've just added the patch titled
soundwire: fix enumeration completion
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
soundwire-fix-enumeration-completion.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c40d6b3249b11d60e09d81530588f56233d9aa44 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan+linaro@xxxxxxxxxx>
Date: Wed, 5 Jul 2023 14:30:11 +0200
Subject: soundwire: fix enumeration completion
From: Johan Hovold <johan+linaro@xxxxxxxxxx>
commit c40d6b3249b11d60e09d81530588f56233d9aa44 upstream.
The soundwire subsystem uses two completion structures that allow
drivers to wait for soundwire device to become enumerated on the bus and
initialised by their drivers, respectively.
The code implementing the signalling is currently broken as it does not
signal all current and future waiters and also uses the wrong
reinitialisation function, which can potentially lead to memory
corruption if there are still waiters on the queue.
Not signalling future waiters specifically breaks sound card probe
deferrals as codec drivers can not tell that the soundwire device is
already attached when being reprobed. Some codec runtime PM
implementations suffer from similar problems as waiting for enumeration
during resume can also timeout despite the device already having been
enumerated.
Fixes: fb9469e54fa7 ("soundwire: bus: fix race condition with enumeration_complete signaling")
Fixes: a90def068127 ("soundwire: bus: fix race condition with initialization_complete signaling")
Cc: stable@xxxxxxxxxxxxxxx # 5.7
Cc: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Cc: Rander Wang <rander.wang@xxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230705123018.30903-2-johan+linaro@xxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/soundwire/bus.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -908,8 +908,8 @@ static void sdw_modify_slave_status(stru
"initializing enumeration and init completion for Slave %d\n",
slave->dev_num);
- init_completion(&slave->enumeration_complete);
- init_completion(&slave->initialization_complete);
+ reinit_completion(&slave->enumeration_complete);
+ reinit_completion(&slave->initialization_complete);
} else if ((status == SDW_SLAVE_ATTACHED) &&
(slave->status == SDW_SLAVE_UNATTACHED)) {
@@ -917,7 +917,7 @@ static void sdw_modify_slave_status(stru
"signaling enumeration completion for Slave %d\n",
slave->dev_num);
- complete(&slave->enumeration_complete);
+ complete_all(&slave->enumeration_complete);
}
slave->status = status;
mutex_unlock(&bus->bus_lock);
@@ -1941,7 +1941,7 @@ int sdw_handle_slave_status(struct sdw_b
"signaling initialization completion for Slave %d\n",
slave->dev_num);
- complete(&slave->initialization_complete);
+ complete_all(&slave->initialization_complete);
/*
* If the manager became pm_runtime active, the peripherals will be
Patches currently in stable-queue which might be from johan+linaro@xxxxxxxxxx are
queue-6.4/pm-sleep-wakeirq-fix-wake-irq-arming.patch
queue-6.4/soundwire-fix-enumeration-completion.patch
queue-6.4/serial-qcom-geni-drop-bogus-runtime-pm-state-update.patch
