Hi, I'm seeing the following warning while roaming to APs operating on different bands. [ 9033.238676] Call Trace: [ 9033.238684] [<ffffffff81064f8b>] warn_slowpath_common+0x7b/0xc0 [ 9033.238688] [<ffffffff81064fe4>] warn_slowpath_null+0x14/0x20 [ 9033.238697] [<ffffffffa0558233>] rate_control_send_low+0xd3/0x140 [mac80211] [ 9033.238704] [<ffffffffa059a9e8>] ath_get_rate+0x48/0x570 [ath9k] [ 9033.238709] [<ffffffff812b3a9c>] ? put_dec+0x10c/0x110 [ 9033.238712] [<ffffffff812b3d8e>] ? number+0x2ee/0x320 [ 9033.238721] [<ffffffffa055805e>] rate_control_get_rate+0x8e/0x190 [mac80211] [ 9033.238730] [<ffffffffa056191c>] invoke_tx_handlers+0xa4c/0x1220 [mac80211] [ 9033.238735] [<ffffffff812b6000>] ? vsnprintf+0x1d0/0x5f0 [ 9033.238744] [<ffffffffa0562175>] ieee80211_tx+0x85/0x240 [mac80211] [ 9033.238749] [<ffffffff814680d0>] ? skb_release_data+0xd0/0xe0 [ 9033.238752] [<ffffffff81469fa2>] ? pskb_expand_head+0x152/0x1e0 [ 9033.238762] [<ffffffffa05623e0>] ieee80211_xmit+0xb0/0x1c0 [mac80211] [ 9033.238765] [<ffffffff81468210>] ? __alloc_skb+0x80/0x190 [ 9033.238774] [<ffffffffa0562544>] ieee80211_tx_skb+0x54/0x70 [mac80211] [ 9033.238782] [<ffffffffa054d26d>] ieee80211_send_delba+0x11d/0x190 [mac80211] [ 9033.238791] [<ffffffffa054e779>] ___ieee80211_stop_rx_ba_session+0x119/0x140 [mac80211] [ 9033.238799] [<ffffffffa054e7f0>] __ieee80211_stop_rx_ba_session+0x50/0x70 [mac80211] [ 9033.238807] [<ffffffffa054d583>] ieee80211_sta_tear_down_BA_sessions+0x43/0x50 [mac80211] [ 9033.238815] [<ffffffffa055276b>] ieee80211_set_disassoc+0x10b/0x220 [mac80211] [ 9033.238820] [<ffffffff811520c6>] ? pollwake+0x56/0x60 [ 9033.238829] [<ffffffffa0553e1d>] ieee80211_mgd_assoc+0x8d/0x360 [mac80211] [ 9033.238838] [<ffffffffa055a34f>] ieee80211_assoc+0x4f/0x80 [mac80211] [ 9033.238855] [<ffffffffa0521186>] __cfg80211_mlme_assoc+0x206/0x290 [cfg80211] [ 9033.238863] [<ffffffffa052129f>] cfg80211_mlme_assoc+0x8f/0xc0 [cfg80211] [ 9033.238869] [<ffffffffa050e0a0>] ? cfg80211_get_dev_from_ifindex+0x70/0x80 [cfg80211] [ 9033.238877] [<ffffffffa0517924>] nl80211_associate+0x224/0x240 [cfg80211] [ 9033.238882] [<ffffffff814978c6>] genl_rcv_msg+0x1e6/0x220 [ 9033.238886] [<ffffffff814976e0>] ? genl_rcv_msg+0x0/0x220 [ 9033.238890] [<ffffffff814965f9>] netlink_rcv_skb+0xa9/0xd0 [ 9033.238893] [<ffffffff814976cc>] genl_rcv+0x2c/0x40 [ 9033.238896] [<ffffffff8149625e>] netlink_unicast+0x2de/0x2f0 [ 9033.238900] [<ffffffff8149704e>] netlink_sendmsg+0x1fe/0x2e0 [ 9033.238903] [<ffffffff814961c9>] ? netlink_unicast+0x249/0x2f0 [ 9033.238908] [<ffffffff8146121b>] sock_sendmsg+0x10b/0x140 [ 9033.238912] [<ffffffff81083580>] ? autoremove_wake_function+0x0/0x40 [ 9033.238917] [<ffffffff81059422>] ? default_wake_function+0x12/0x20 [ 9033.238922] [<ffffffff81049f29>] ? __wake_up_common+0x59/0x90 [ 9033.238925] [<ffffffff81460774>] ? move_addr_to_kernel+0x64/0x70 [ 9033.238929] [<ffffffff8146b969>] ? verify_iovec+0x69/0xc0 [ 9033.238932] [<ffffffff81461683>] sys_sendmsg+0x233/0x3a0 [ 9033.238935] [<ffffffff810517d3>] ? __wake_up+0x53/0x70 [ 9033.238939] [<ffffffff81140132>] ? vfs_write+0x132/0x1a0 [ 9033.238942] [<ffffffff81140951>] ? sys_write+0x51/0x80 [ 9033.238947] [<ffffffff810131f2>] system_call_fastpath+0x16/0x1b [ 9033.238950] ---[ end trace 5655896580a8ccea ]--- This happens because the station tries to close its BACK negotiation with the existing AP but on a channel where it got authenticated with a newer AP. ieee80211_work_work() configures the station back to its operating channel after the authentication with the new AP, but sometimes we get assoc req before this. One (may be not good)fix can be making sure if station is in operating channel before cleaning up its BACK state. Not quite sure about a clean fix here. Thanks, Vasanth -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
