Re: [PATCH v5 0/2] mac80211: Trigger disconnect for STA during target hardware restart

From: Brian Norris
Date: Tue Mar 08 2022 - 13:13:38 EST


On Tue, Mar 08, 2022 at 05:23:23PM +0530, Youghandhar Chintala wrote:
> Currently in case of target hardware restart ,we just reconfig and
> re-enable the security keys and enable the network queues to start
> data traffic back from where it was interrupted.
>
> Many ath10k wifi chipsets have sequence numbers for the data
> packets assigned by firmware and the mac sequence number will
> restart from zero after target hardware restart leading to mismatch
> in the sequence number expected by the remote peer vs the sequence
> number of the frame sent by the target firmware.
>
> This mismatch in sequence number will cause out-of-order packets
> on the remote peer and all the frames sent by the device are dropped
> until we reach the sequence number which was sent before we restarted
> the target hardware
>
> In order to fix this, we trigger a disconnect in case of hardware
> restart. After this there will be a fresh connection and thereby
> avoiding the dropping of frames by remote peer.
>
> The right fix would be to pull the entire data path into the host
> which is not feasible or would need lots of complex/inefficient
> datapath changes.
>
> ---
> Changes from v3:
> - Fixed commit text errors
> - Remove excess space in "hardware restart"
> - Removed blank line between the function description and the arguments

For whatever it's worth, the series looks good to me:

Reviewed-by: Brian Norris <briannorris@xxxxxxxxxxxx>