Re: [PATCH v2][next] wifi: ath6kl: wmi: Avoid -Wflex-array-member-not-at-end warning

[Gustavo A. R. Silva]

> > @@ -1652,7 +1656,7 @@ struct roam_ctrl_cmd {
> >   	union {
> >   		u8 bssid[ETH_ALEN]; /* WMI_FORCE_ROAM */
> >   		u8 roam_mode; /* WMI_SET_ROAM_MODE */
> > -		struct bss_bias_info bss; /* WMI_SET_HOST_BIAS */
> > +		struct bss_bias_info_hdr bss; /* WMI_SET_HOST_BIAS */
> >   		struct low_rssi_scan_params params; /* WMI_SET_LRSSI_SCAN_PARAMS
> >   						     */
> >   	} __packed info;
>
> That bss member appears to be completely unused
> (bssid, roam_mode, and params are used)
>
> So IMO the better solution is to remove bss from the union.
> And I think struct bss_bias and struct bss_bias_info can also be removed.

Even if they're not used, are you sure they aren't there simply	
to define the memory layout of struct roam_ctrl_cmd?

As Kees commented[1], struct roam_ctrl_cmd appears to be a
hardware interface... See below:

drivers/net/wireless/ath/ath6kl/wmi.c:
 755 /*
 756  * Mechanism to modify the roaming behavior in the firmware. The lower rssi
 757  * at which the station has to roam can be passed with
 758  * WMI_SET_LRSSI_SCAN_PARAMS. Subtract 96 from RSSI to get the signal level
 759  * in dBm.
 760  */
 761 int ath6kl_wmi_set_roam_lrssi_cmd(struct wmi *wmi, u8 lrssi)
 762 {
 763         struct sk_buff *skb;
 764         struct roam_ctrl_cmd *cmd;
 765
 766         skb = ath6kl_wmi_get_new_buf(sizeof(*cmd));
 767         if (!skb)
 768                 return -ENOMEM;
 769
 770         cmd = (struct roam_ctrl_cmd *) skb->data;
...
}

Thanks
-Gustavo

[1] https://lore.kernel.org/linux-hardening/202601151627.99DFE54@keescook/