6.17-stable review patch. If anyone has any objections, please let me know.
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From: Jeffrey Hugo quic_jhugo@quicinc.com
[ Upstream commit fd6e385528d8f85993b7bfc6430576136bb14c65 ]
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: 5f8df5c6def6 ("accel/qaic: Add bootlog debugfs") Signed-off-by: Jeffrey Hugo quic_jhugo@quicinc.com Signed-off-by: Youssef Samir youssef.abdulrahman@oss.qualcomm.com Reviewed-by: Jeff Hugo jeff.hugo@oss.qualcomm.com Reviewed-by: Carl Vanderlip carl.vanderlip@oss.qualcomm.com Signed-off-by: Jeff Hugo jeff.hugo@oss.qualcomm.com Link: https://lore.kernel.org/r/20251007115750.332169-1-youssef.abdulrahman@oss.qu... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/accel/qaic/qaic_debugfs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/accel/qaic/qaic_debugfs.c b/drivers/accel/qaic/qaic_debugfs.c index a991b8198dc40..8dc4fe5bb560e 100644 --- a/drivers/accel/qaic/qaic_debugfs.c +++ b/drivers/accel/qaic/qaic_debugfs.c @@ -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: