This is a note to let you know that I've just added the patch titled Bluetooth: btmtksdio: Fix kernel oops in btmtksdio_interrupt to the 5.15-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: bluetooth-btmtksdio-fix-kernel-oops-in-btmtksdio_int.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 31e80bcd7113d4d058b15030692a9fbb09b1d361 Author: Yake Yang <yake.yang@xxxxxxxxxxxx> Date: Thu Mar 17 07:15:19 2022 +0800 Bluetooth: btmtksdio: Fix kernel oops in btmtksdio_interrupt [ Upstream commit b062a0b9c1dc1ff63094337dccfe1568d5b62023 ] Fix the following kernel oops in btmtksdio_interrrupt [ 14.339134] btmtksdio_interrupt+0x28/0x54 [ 14.339139] process_sdio_pending_irqs+0x68/0x1a0 [ 14.339144] sdio_irq_work+0x40/0x70 [ 14.339154] process_one_work+0x184/0x39c [ 14.339160] worker_thread+0x228/0x3e8 [ 14.339168] kthread+0x148/0x3ac [ 14.339176] ret_from_fork+0x10/0x30 That happened because hdev->power_on is already called before sdio_set_drvdata which btmtksdio_interrupt handler relies on is not properly set up. The details are shown as the below: hci_register_dev would run queue_work(hdev->req_workqueue, &hdev->power_on) as WQ_HIGHPRI workqueue_struct to complete the power-on sequeunce and thus hci_power_on may run before sdio_set_drvdata is done in btmtksdio_probe. The hci_dev_do_open in hci_power_on would initialize the device and enable the interrupt and thus it is possible that btmtksdio_interrupt is being called right before sdio_set_drvdata is filled out. When btmtksdio_interrupt is being called and sdio_set_drvdata is not filled , the kernel oops is going to happen because btmtksdio_interrupt access an uninitialized pointer. Fixes: 9aebfd4a2200 ("Bluetooth: mediatek: add support for MediaTek MT7663S and MT7668S SDIO devices") Reviewed-by: Mark Chen <markyawenchen@xxxxxxxxx> Co-developed-by: Sean Wang <sean.wang@xxxxxxxxxxxx> Signed-off-by: Sean Wang <sean.wang@xxxxxxxxxxxx> Signed-off-by: Yake Yang <yake.yang@xxxxxxxxxxxx> Signed-off-by: Marcel Holtmann <marcel@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/bluetooth/btmtksdio.c b/drivers/bluetooth/btmtksdio.c index 1cbdeca1fdc4..ff1f5dfbb6db 100644 --- a/drivers/bluetooth/btmtksdio.c +++ b/drivers/bluetooth/btmtksdio.c @@ -981,6 +981,8 @@ static int btmtksdio_probe(struct sdio_func *func, hdev->manufacturer = 70; set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks); + sdio_set_drvdata(func, bdev); + err = hci_register_dev(hdev); if (err < 0) { dev_err(&func->dev, "Can't register HCI device\n"); @@ -988,8 +990,6 @@ static int btmtksdio_probe(struct sdio_func *func, return err; } - sdio_set_drvdata(func, bdev); - /* pm_runtime_enable would be done after the firmware is being * downloaded because the core layer probably already enables * runtime PM for this func such as the case host->caps &