[PATCH v2] ath10k: fix wmi mgmt tx queue full due to race condition

[Brian Norris]

On Mon, Dec 21, 2020 at 10:34 PM Miaoqing Pan <miaoqing at codeaurora.org> wrote:
>
> Failed to transmit wmi management frames:
>
> [84977.840894] ath10k_snoc a000000.wifi: wmi mgmt tx queue is full
> [84977.840913] ath10k_snoc a000000.wifi: failed to transmit packet, dropping: -28
> [84977.840924] ath10k_snoc a000000.wifi: failed to submit frame: -28
> [84977.840932] ath10k_snoc a000000.wifi: failed to transmit frame: -28
>
> This issue is caused by race condition between skb_dequeue and
> __skb_queue_tail. The queue of ‘wmi_mgmt_tx_queue’ is protected by a
> different lock: ar->data_lock vs list->lock, the result is no protection.

Reviewed-by: Brian Norris <briannorris at chromium.org>