• Youghandhar Chintala's avatar
    mac80211: Add support to trigger sta disconnect on hardware restart · 7d352ccf
    Youghandhar Chintala authored
    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 sta disconnect, in case of target
    hw 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 changes and
    will still be inefficient.
    
    Tested on ath10k using WCN3990, QCA6174
    Signed-off-by: default avatarYoughandhar Chintala <youghand@codeaurora.org>
    Link: https://lore.kernel.org/r/20220308115325.5246-2-youghand@codeaurora.orgSigned-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
    7d352ccf
util.c 125 KB