From 35bdafda40cc343ad2ba2cce105eba03a70241cc Mon Sep 17 00:00:00 2001

From: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>

Date: Fri, 31 Mar 2023 18:06:34 +0200

Subject: [PATCH] remoteproc: stm32_rproc: Add mutex protection for workqueue

Git-commit: 35bdafda40cc343ad2ba2cce105eba03a70241cc

Patch-mainline: v6.4-rc1

References: git-fixes

The workqueue may execute late even after remoteproc is stopped or

stopping, some resources (rpmsg device and endpoint) have been

released in rproc_stop_subdevices(), then rproc_vq_interrupt()

accessing these resources will cause kernel dump.

Call trace:

virtqueue_add_inbuf

virtqueue_add_inbuf

rpmsg_recv_single

rpmsg_recv_done

vring_interrupt

stm32_rproc_mb_vq_work

process_one_work

worker_thread

kthread

Suggested-by: Mathieu Poirier <mathieu.poirier@linaro.org>

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>

Link: https://lore.kernel.org/r/20230331160634.3113031-1-arnaud.pouliquen@foss.st.com

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/remoteproc/stm32_rproc.c | 8 ++++++++

 1 file changed, 8 insertions(+)

diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c

index 23c1690b8d73..8746cbb1f168 100644

--- a/drivers/remoteproc/stm32_rproc.c

+++ b/drivers/remoteproc/stm32_rproc.c

@@ -291,8 +291,16 @@ static void stm32_rproc_mb_vq_work(struct work_struct *work)

 	struct stm32_mbox *mb = container_of(work, struct stm32_mbox, vq_work);

 	struct rproc *rproc = dev_get_drvdata(mb->client.dev);

+	mutex_lock(&rproc->lock);

+

+	if (rproc->state != RPROC_RUNNING)

+		goto unlock_mutex;

+

 	if (rproc_vq_interrupt(rproc, mb->vq_id) == IRQ_NONE)

 		dev_dbg(&rproc->dev, "no message found in vq%d\n", mb->vq_id);

+

+unlock_mutex:

+	mutex_unlock(&rproc->lock);

 }

 static void stm32_rproc_mb_callback(struct mbox_client *cl, void *data)

-- 

2.35.3