Commit fd6e3855 authored by Jeff Hugo's avatar Jeff Hugo
Browse files

accel/qaic: Fix bootlog initialization ordering 



As soon as we queue MHI buffers to receive the bootlog from the device,
we could be receiving data. Therefore all the resources needed to
process that data need to be setup prior to queuing the buffers.

We currently initialize some of the resources after queuing the buffers
which creates a race between the probe() and any data that comes back
from the device. If the uninitialized resources are accessed, we could
see page faults.

Fix the init ordering to close the race.

Fixes: 5f8df5c6 ("accel/qaic: Add bootlog debugfs")
Signed-off-by: default avatarJeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: default avatarYoussef Samir <youssef.abdulrahman@oss.qualcomm.com>
Reviewed-by: default avatarJeff Hugo <jeff.hugo@oss.qualcomm.com>
Reviewed-by: default avatarCarl Vanderlip <carl.vanderlip@oss.qualcomm.com>
Signed-off-by: default avatarJeff Hugo <jeff.hugo@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20251007115750.332169-1-youssef.abdulrahman@oss.qualcomm.com
parent 48a71076

drivers/accel/qaic/qaic_debugfs.c

+3 −2
Original line number Diff line number Diff line
@@ -218,6 +218,9 @@ static int qaic_bootlog_mhi_probe(struct mhi_device *mhi_dev, const struct mhi_d 
	if (ret)

		goto destroy_workqueue;



	dev_set_drvdata(&mhi_dev->dev, qdev);

	qdev->bootlog_ch = mhi_dev;



	for (i = 0; i < BOOTLOG_POOL_SIZE; i++) {

		msg = devm_kzalloc(&qdev->pdev->dev, sizeof(*msg), GFP_KERNEL);

		if (!msg) {
@@ -233,8 +236,6 @@ static int qaic_bootlog_mhi_probe(struct mhi_device *mhi_dev, const struct mhi_d 
			goto mhi_unprepare;

	}



	dev_set_drvdata(&mhi_dev->dev, qdev);

	qdev->bootlog_ch = mhi_dev;

	return 0;



mhi_unprepare: