[PATCH v2] Bluetooth: btnxpuart: Fix btnxpuart_close

From: Francesco Dolcini
Date: Mon Mar 04 2024 - 13:14:56 EST


From: Marcel Ziswiler <marcel.ziswiler@xxxxxxxxxxx>

Fix scheduling while atomic BUG in btnxpuart_close(), properly
purge the transmit queue and free the receive skb.

[ 10.973809] BUG: scheduling while atomic: kworker/u9:0/80/0x00000002
..
[ 10.980740] CPU: 3 PID: 80 Comm: kworker/u9:0 Not tainted 6.8.0-rc7-0.0.0-devel-00005-g61fdfceacf09 #1
[ 10.980751] Hardware name: Toradex Verdin AM62 WB on Dahlia Board (DT)
[ 10.980760] Workqueue: hci0 hci_power_off [bluetooth]
[ 10.981169] Call trace:
..
[ 10.981363] uart_update_mctrl+0x58/0x78
[ 10.981373] uart_dtr_rts+0x104/0x114
[ 10.981381] tty_port_shutdown+0xd4/0xdc
[ 10.981396] tty_port_close+0x40/0xbc
[ 10.981407] uart_close+0x34/0x9c
[ 10.981414] ttyport_close+0x50/0x94
[ 10.981430] serdev_device_close+0x40/0x50
[ 10.981442] btnxpuart_close+0x24/0x98 [btnxpuart]
[ 10.981469] hci_dev_close_sync+0x2d8/0x718 [bluetooth]
[ 10.981728] hci_dev_do_close+0x2c/0x70 [bluetooth]
[ 10.981862] hci_power_off+0x20/0x64 [bluetooth]

Fixes: 689ca16e5232 ("Bluetooth: NXP: Add protocol support for NXP Bluetooth chipsets")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@xxxxxxxxxxx>
Reviewed-by: Neeraj Sanjay Kale <neeraj.sanjaykale@xxxxxxx>
[ fd: reword commit message ]
Signed-off-by: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>
---
v2:
- reword commit message
- added rb neeraj
v1: https://lore.kernel.org/all/20231018145540.34014-2-marcel@xxxxxxxxxxxx/
---
drivers/bluetooth/btnxpuart.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/bluetooth/btnxpuart.c b/drivers/bluetooth/btnxpuart.c
index 55b6e3dcd4ec..0b93c2ff29e4 100644
--- a/drivers/bluetooth/btnxpuart.c
+++ b/drivers/bluetooth/btnxpuart.c
@@ -1252,6 +1252,9 @@ static int btnxpuart_close(struct hci_dev *hdev)

ps_wakeup(nxpdev);
serdev_device_close(nxpdev->serdev);
+ skb_queue_purge(&nxpdev->txq);
+ kfree_skb(nxpdev->rx_skb);
+ nxpdev->rx_skb = NULL;
clear_bit(BTNXPUART_SERDEV_OPEN, &nxpdev->tx_state);
return 0;
}
--
2.39.2