6.6-stable review patch. If anyone has any objections, please let me know.
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From: Neeraj Sanjay Kale neeraj.sanjaykale@nxp.com
[ Upstream commit 35237475384ab3622f63c3c09bdf6af6dacfe9c3 ]
This fixes the random kernel crash seen while removing the driver, when running the load/unload test over multiple iterations.
1) modprobe btnxpuart 2) hciconfig hci0 reset 3) hciconfig (check hci0 interface up with valid BD address) 4) modprobe -r btnxpuart Repeat steps 1 to 4
The ps_wakeup() call in btnxpuart_close() schedules the psdata->work(), which gets scheduled after module is removed, causing a kernel crash.
This hidden issue got highlighted after enabling Power Save by default in 4183a7be7700 (Bluetooth: btnxpuart: Enable Power Save feature on startup)
The new ps_cleanup() deasserts UART break immediately while closing serdev device, cancels any scheduled ps_work and destroys the ps_lock mutex.
[ 85.884604] Unable to handle kernel paging request at virtual address ffffd4a61638f258 [ 85.884624] Mem abort info: [ 85.884625] ESR = 0x0000000086000007 [ 85.884628] EC = 0x21: IABT (current EL), IL = 32 bits [ 85.884633] SET = 0, FnV = 0 [ 85.884636] EA = 0, S1PTW = 0 [ 85.884638] FSC = 0x07: level 3 translation fault [ 85.884642] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000041dd0000 [ 85.884646] [ffffd4a61638f258] pgd=1000000095fff003, p4d=1000000095fff003, pud=100000004823d003, pmd=100000004823e003, pte=0000000000000000 [ 85.884662] Internal error: Oops: 0000000086000007 [#1] PREEMPT SMP [ 85.890932] Modules linked in: algif_hash algif_skcipher af_alg overlay fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine authenc libdes crct10dif_ce polyval_ce polyval_generic snd_soc_imx_spdif snd_soc_imx_card snd_soc_ak5558 snd_soc_ak4458 caam secvio error snd_soc_fsl_spdif snd_soc_fsl_micfil snd_soc_fsl_sai snd_soc_fsl_utils gpio_ir_recv rc_core fuse [last unloaded: btnxpuart(O)] [ 85.927297] CPU: 1 PID: 67 Comm: kworker/1:3 Tainted: G O 6.1.36+g937b1be4345a #1 [ 85.936176] Hardware name: FSL i.MX8MM EVK board (DT) [ 85.936182] Workqueue: events 0xffffd4a61638f380 [ 85.936198] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 85.952817] pc : 0xffffd4a61638f258 [ 85.952823] lr : 0xffffd4a61638f258 [ 85.952827] sp : ffff8000084fbd70 [ 85.952829] x29: ffff8000084fbd70 x28: 0000000000000000 x27: 0000000000000000 [ 85.963112] x26: ffffd4a69133f000 x25: ffff4bf1c8540990 x24: ffff4bf215b87305 [ 85.963119] x23: ffff4bf215b87300 x22: ffff4bf1c85409d0 x21: ffff4bf1c8540970 [ 85.977382] x20: 0000000000000000 x19: ffff4bf1c8540880 x18: 0000000000000000 [ 85.977391] x17: 0000000000000000 x16: 0000000000000133 x15: 0000ffffe2217090 [ 85.977399] x14: 0000000000000001 x13: 0000000000000133 x12: 0000000000000139 [ 85.977407] x11: 0000000000000001 x10: 0000000000000a60 x9 : ffff8000084fbc50 [ 85.977417] x8 : ffff4bf215b7d000 x7 : ffff4bf215b83b40 x6 : 00000000000003e8 [ 85.977424] x5 : 00000000410fd030 x4 : 0000000000000000 x3 : 0000000000000000 [ 85.977432] x2 : 0000000000000000 x1 : ffff4bf1c4265880 x0 : 0000000000000000 [ 85.977443] Call trace: [ 85.977446] 0xffffd4a61638f258 [ 85.977451] 0xffffd4a61638f3e8 [ 85.977455] process_one_work+0x1d4/0x330 [ 85.977464] worker_thread+0x6c/0x430 [ 85.977471] kthread+0x108/0x10c [ 85.977476] ret_from_fork+0x10/0x20 [ 85.977488] Code: bad PC value [ 85.977491] ---[ end trace 0000000000000000 ]---
Preset since v6.9.11 Fixes: 86d55f124b52 ("Bluetooth: btnxpuart: Deasset UART break before closing serdev device") Signed-off-by: Neeraj Sanjay Kale neeraj.sanjaykale@nxp.com Reviewed-by: Paul Menzel pmenzel@molgen.mpg.de Signed-off-by: Luiz Augusto von Dentz luiz.von.dentz@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/bluetooth/btnxpuart.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-)
diff --git a/drivers/bluetooth/btnxpuart.c b/drivers/bluetooth/btnxpuart.c index f72086ee614fb..814dd966b1a45 100644 --- a/drivers/bluetooth/btnxpuart.c +++ b/drivers/bluetooth/btnxpuart.c @@ -438,6 +438,23 @@ static bool ps_wakeup(struct btnxpuart_dev *nxpdev) return false; }
+static void ps_cleanup(struct btnxpuart_dev *nxpdev) +{ + struct ps_data *psdata = &nxpdev->psdata; + u8 ps_state; + + mutex_lock(&psdata->ps_lock); + ps_state = psdata->ps_state; + mutex_unlock(&psdata->ps_lock); + + if (ps_state != PS_STATE_AWAKE) + ps_control(psdata->hdev, PS_STATE_AWAKE); + + ps_cancel_timer(nxpdev); + cancel_work_sync(&psdata->work); + mutex_destroy(&psdata->ps_lock); +} + static int send_ps_cmd(struct hci_dev *hdev, void *data) { struct btnxpuart_dev *nxpdev = hci_get_drvdata(hdev); @@ -1307,7 +1324,6 @@ static int btnxpuart_close(struct hci_dev *hdev) { struct btnxpuart_dev *nxpdev = hci_get_drvdata(hdev);
- ps_wakeup(nxpdev); serdev_device_close(nxpdev->serdev); skb_queue_purge(&nxpdev->txq); kfree_skb(nxpdev->rx_skb); @@ -1457,8 +1473,8 @@ static void nxp_serdev_remove(struct serdev_device *serdev) nxpdev->new_baudrate = nxpdev->fw_init_baudrate; nxp_set_baudrate_cmd(hdev, NULL); } - ps_cancel_timer(nxpdev); } + ps_cleanup(nxpdev); hci_unregister_dev(hdev); hci_free_dev(hdev); }