On Thursday 21 January 2016 12:56:01 Sven Eckelmann wrote:
Just installed in on some hardware (2x OM5P + OpenWrt 44654 + compat-wireless 2015-10-26) and enabled BATMAN_V.
[ 168.540000] CPU 0 Unable to handle kernel paging request at virtual address fffffff0, epc == 86d8301c, ra == 86d8301c [ 168.550000] Oops[#1]: [ 168.550000] CPU: 0 PID: 265 Comm: kworker/u2:2 Tainted: P 3.18.8 #1 [ 168.550000] Workqueue: bat_events batadv_v_elp_throughput_metric_update [batman_adv]
[..]
[ 168.550000] epc : 86d8301c batadv_v_elp_throughput_metric_update+0x20/0x58 [batman_adv] [ 168.550000] Tainted: P [ 168.550000] ra : 86d8301c batadv_v_elp_throughput_metric_update+0x20/0x58 [batman_adv]
Who knew that struct station_info changed in v3.18-6219-g6de3980, v3.18-6235-gb51f3be and v3.18-6217-ga76b194? Wieder keiner!? :)
So what basically happened was a stack corruption causing the return address to be bogus. This only happened because the kernel version of cfg80211.h (which is used to compile batman-adv) is different than the version in the mac80211 package (which is used at runtime) I have now synced that structure between the OpenWrt kernel and the used compat-wireless, rebuild my OpenWrt and tried again. I hope this helps anyone trying to use B.A.T.M.A.N. V on OpenWrt.
@Felix, would it be ok for you when I propose a "*-sync-cfg80211-station_info.patch" for the 3.18 generic kernel patches? Or do you have a good idea how to force the openwrt-routing batman-adv package against the cfg80211.h of compat-wireless?
Kind regards, Sven