Sven Eckelmann <sven@xxxxxxxxxxxxx> wrote:
> The driver_data area of ieee80211_tx_info is used in ath11k for
> ath11k_skb_cb. The first function in the TX patch which rewrites it to
> ath11k_skb_cb is already ath11k_mac_op_tx. No one else in the code path
> must use it for something else before it reinitializes it. Otherwise the
> data has to be considered uninitialized or corrupt.
>
> But the ieee80211_tx_info.control shares exactly the same area as
> ieee80211_tx_info.driver_data and ath11k is still using it. This results in
> best case in a
>
> ath11k c000000.wifi1: no vif found for mgmt frame, flags 0x0
>
> or (slightly worse) in a kernel oops.
>
> Instead, the interesting data must be moved first into the ath11k_skb_cb
> and ieee80211_tx_info.control must then not be used anymore.
>
> Tested-on: IPQ8074 hw2.0 WLAN.HK.2.4.0.1.r1-00026-QCAHKSWPL_SILICONZ-2
>
> Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")
> Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx>
> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
3 patches applied to ath-next branch of ath.git, thanks.
f4d291b43f80 ath11k: Don't cast ath11k_skb_cb to ieee80211_tx_info.control
5da7acfec5ec ath11k: Reset ath11k_skb_cb before setting new flags
d35d1375493b ath11k: Build check size of ath11k_skb_cb
--
https://patchwork.kernel.org/project/linux-wireless/patch/20201119154235.263250-1-sven@xxxxxxxxxxxxx/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
