W dniu 14.06.2022 o 20:17, Max Krummenacher pisze:
> From: Max Krummenacher <max.krummenacher@xxxxxxxxxxx>
>
> This reverts commit ff7f2926114d3a50f5ffe461a9bce8d761748da5.
>
> The commit ff7f2926114d ("Bluetooth: core: Fix missing power_on work
> cancel on HCI close") introduced between v5.18 and v5.19-rc1 makes
> going to suspend freeze. v5.19-rc2 is equally affected.
>
> This has been seen on a Colibri iMX6ULL WB which has a Marvell 8997
> based WiFi / Bluetooth module connected over SDIO.
> [...]
Hello,
commit ff7f2926114d ("Bluetooth: core: Fix missing power_on work cancel on HCI close")
causes problems also on my laptop (HP 17-by0001nw with a Realtek Bluetooth adapter).
I have Bluetooth disabled by default on startup (via systemd-rfkill.service ) and
vanilla kernel 5.19.0-rc5 fails to suspend (the screen turns black, but I am then able to
touch a trackpad and log in). Reverting that commit on top of 5.19.0-rc5 fixes the issue.
On bare 5.19.0-rc5, after startup, the kworker/u9:0+hci0 process hangs indefinitely
with this stacktrace (obtained through "cat /proc/163/stack" )
[<0>] __flush_work+0x143/0x220
[<0>] __cancel_work_timer+0x122/0x1a0
[<0>] cancel_work_sync+0x10/0x20
[<0>] hci_dev_close_sync+0x2a/0x550 [bluetooth]
[<0>] hci_dev_do_close+0x2a/0x60 [bluetooth]
[<0>] hci_power_on+0x91/0x200 [bluetooth]
[<0>] process_one_work+0x21c/0x3c0
[<0>] worker_thread+0x4a/0x3a0
[<0>] kthread+0xcf/0xf0
[<0>] ret_from_fork+0x22/0x30
It appears that the hci_power_on() function calls hci_dev_do_close() in this block:
if (hci_dev_test_flag(hdev, HCI_RFKILLED) ||
/* [...] */ ) {
hci_dev_clear_flag(hdev, HCI_AUTO_OFF);
hci_dev_do_close(hdev);
} else /* [...] */
which then calls hci_dev_close_sync(). With the problematic commit, that function
calls
cancel_work_sync(&hdev->power_on)
which tries to cancel the execution of the hci_power_on() function's itself, which leads to a deadlock.
When trying to suspend, the "/lib/systemd/systemd-sleep suspend" process hangs on
[<0>] hci_suspend_dev+0x87/0xf0 [bluetooth]
[<0>] hci_suspend_notifier+0x38/0x80 [bluetooth]
[<0>] notifier_call_chain_robust+0x5e/0xc0
[<0>] blocking_notifier_call_chain_robust+0x42/0x60
[<0>] pm_notifier_call_chain_robust+0x1d/0x40
[<0>] pm_suspend+0x116/0x5a0
[<0>] state_store+0x82/0xe0
[<0>] kobj_attr_store+0x12/0x20
[<0>] sysfs_kf_write+0x3e/0x50
[<0>] kernfs_fop_write_iter+0x138/0x1c0
[<0>] new_sync_write+0x104/0x180
[<0>] vfs_write+0x1d7/0x260
[<0>] ksys_write+0x67/0xe0
[<0>] __x64_sys_write+0x1a/0x20
[<0>] do_syscall_64+0x3b/0x90
[<0>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
My device is:
Bus 001 Device 005: ID 0bda:b00b Realtek Semiconductor Corp. Bluetooth Radio
So probably the
commit ff7f2926114d ("Bluetooth: core: Fix missing power_on work cancel on HCI close")
should be reverted or corrected.
Greetings,
Mateusz Jończyk
> Signed-off-by: Max Krummenacher <max.krummenacher@xxxxxxxxxxx>
> ---
>
> net/bluetooth/hci_core.c | 2 ++
> net/bluetooth/hci_sync.c | 1 -
> 2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 59a5c1341c26..19df3905c5f8 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -2675,6 +2675,8 @@ void hci_unregister_dev(struct hci_dev *hdev)
> list_del(&hdev->list);
> write_unlock(&hci_dev_list_lock);
>
> + cancel_work_sync(&hdev->power_on);
> +
> hci_cmd_sync_clear(hdev);
>
> if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks))
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 286d6767f017..1739e8cb3291 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -4088,7 +4088,6 @@ int hci_dev_close_sync(struct hci_dev *hdev)
>
> bt_dev_dbg(hdev, "");
>
> - cancel_work_sync(&hdev->power_on);
> cancel_delayed_work(&hdev->power_off);
> cancel_delayed_work(&hdev->ncmd_timer);
>
