Hi !
I'm about to add monitor mode to my cfg80211 code. I wanted to
keep as much of the monitor mode code from libertas that I could,
mainly
* priv->rtap_net_dev
* lbs_rtap_XXX() in main.c
* process_rxed_802_11_packet() in rx.c.
So my code is quite simply currently:
static struct cfg80211_ops lbs_cfg80211_ops = {
// ...
.change_virtual_intf = lbs_change_intf,
};
static int lbs_change_intf(struct wiphy *wiphy, struct net_device *dev,
enum nl80211_iftype type, u32 *flags,
struct vif_params *params)
{
struct lbs_private *priv = wiphy_priv(wiphy);
int ret = 0;
lbs_deb_enter(LBS_DEB_CFG80211);
switch(type) {
case NL80211_IFTYPE_MONITOR:
ret = lbs_enable_monitor_mode(priv, type == NL80211_IFTYPE_MONITOR);
if (!priv->rtap_net_dev)
lbs_add_rtap(priv);
if (ret)
goto done;
break;
// ...
However, when I now run "iw wlan0 interface type monitor", I get
this in dmesg:
[ 9366.886670] libertas enter: lbs_change_intf()
[ 9366.886765] ##HS type 6
[ 9366.886844] libertas enter: lbs_enable_monitor_mode()
[ 9366.886932] libertas enter: lbs_is_cmd_allowed()
[ 9366.887018] libertas leave: lbs_is_cmd_allowed()
[ 9366.887454] libertas cmd: DNLD_CMD: command 0x0098, seq 5, size 12
[ 9366.887545] libertas DNLD_CMD: 98 00 0c 00 05 00 00 00 01 00 01 00
[ 9366.892052] libertas cmd: CMD_RESP: response 0x8098, seq 5, size 12
[ 9366.892060] libertas CMD_RESP: 98 80 0c 00 05 00 02 00 01 00 01 00
[ 9366.892104] libertas: PREP_CMD: command 0x0098 failed: 2
[ 9366.892114] libertas leave: lbs_enable_monitor_mode()
[ 9366.892121] libertas enter: lbs_add_rtap()
[ 9366.892277]
[ 9366.892280] =============================================
[ 9366.892286] [ INFO: possible recursive locking detected ]
[ 9366.892293] 2.6.32-rc5-wl #24
[ 9366.892298] ---------------------------------------------
[ 9366.892304] iw/2782 is trying to acquire lock:
[ 9366.892311] (rtnl_mutex){+.+.+.}, at: [<c03447c1>] rtnl_lock+0xf/0x11
[ 9366.892331]
[ 9366.892334] but task is already holding lock:
[ 9366.892340] (rtnl_mutex){+.+.+.}, at: [<c03447c1>] rtnl_lock+0xf/0x11
[ 9366.892354]
[ 9366.892356] other info that might help us debug this:
[ 9366.892364] 3 locks held by iw/2782:
[ 9366.892369] #0: (genl_mutex){+.+.+.}, at: [<c034c652>] genl_rcv+0x12/0x2b
[ 9366.892386] #1: (rtnl_mutex){+.+.+.}, at: [<c03447c1>] rtnl_lock+0xf/0x11
[ 9366.892401] #2: (&rdev->mtx){+.+.+.}, at: [<f97d0810>] cfg80211_get_dev_from_ifindex+0x4f/0x66 [cfg80211]
[ 9366.892432]
[ 9366.892435] stack backtrace:
[ 9366.892443] Pid: 2782, comm: iw Not tainted 2.6.32-rc5-wl #24
[ 9366.892449] Call Trace:
[ 9366.892463] [<c01419d7>] validate_chain+0x49b/0xb62
[ 9366.892476] [<c01427bf>] __lock_acquire+0x721/0x787
[ 9366.892489] [<c0140713>] ? trace_hardirqs_on_caller+0x107/0x12f
[ 9366.892500] [<c0142881>] lock_acquire+0x5c/0x73
[ 9366.892511] [<c03447c1>] ? rtnl_lock+0xf/0x11
[ 9366.892525] [<c0399976>] mutex_lock_nested+0x47/0x28f
[ 9366.892536] [<c03447c1>] ? rtnl_lock+0xf/0x11
[ 9366.892548] [<c03488dc>] ? ether_setup+0x0/0x5c
[ 9366.892560] [<c03447c1>] rtnl_lock+0xf/0x11
[ 9366.892572] [<c033c96e>] register_netdev+0xc/0x3f
[ 9366.892594] [<f98ed2f6>] lbs_add_rtap+0xb4/0x10f [libertas]
[ 9366.892612] [<f98e6e1f>] lbs_change_intf+0x8c/0x4c9 [libertas]
[ 9366.892636] [<f97d1905>] cfg80211_change_iface+0x9f/0xd5 [cfg80211]
[ 9366.892663] [<f97d7886>] nl80211_set_interface+0xc1/0xff [cfg80211]
[ 9366.892676] [<c034d774>] genl_rcv_msg+0x140/0x15c
[ 9366.892688] [<c034d634>] ? genl_rcv_msg+0x0/0x15c
[ 9366.892698] [<c034b15d>] netlink_rcv_skb+0x30/0x75
[ 9366.892709] [<c034c65e>] genl_rcv+0x1e/0x2b
[ 9366.892719] [<c034af3c>] netlink_unicast+0x1b7/0x229
[ 9366.892731] [<c034ba58>] netlink_sendmsg+0x21b/0x228
[ 9366.892744] [<c032fe2a>] sock_sendmsg+0xca/0xe1
[ 9366.892758] [<c0133b8d>] ? autoremove_wake_function+0x0/0x33
[ 9366.892770] [<c0142928>] ? lock_release_non_nested+0x90/0x1fc
[ 9366.892781] [<c01613c0>] ? might_fault+0x4e/0x88
[ 9366.892792] [<c01613c0>] ? might_fault+0x4e/0x88
[ 9366.892805] [<c01fcea0>] ? copy_from_user+0x31/0x54
[ 9366.892816] [<c033721b>] ? verify_iovec+0x40/0x71
[ 9366.892827] [<c032ff90>] sys_sendmsg+0x14f/0x1aa
[ 9366.892841] [<c01427e2>] ? __lock_acquire+0x744/0x787
[ 9366.892853] [<c0142928>] ? lock_release_non_nested+0x90/0x1fc
[ 9366.892863] [<c01613c0>] ? might_fault+0x4e/0x88
[ 9366.892877] [<c0330d7a>] sys_socketcall+0x144/0x178
[ 9366.892889] [<c01fcab4>] ? trace_hardirqs_on_thunk+0xc/0x10
[ 9366.892900] [<c0102888>] sysenter_do_call+0x12/0x36
So it seems I cannot call register_netdev() while in
cfg80211_change_iface(), right ? What would be a proper
approach then?
---
http://www.holgerschurig.de
On Tue, 2009-10-20 at 12:36 +0200, Holger Schurig wrote:
> Hi !
>
> I'm about to add monitor mode to my cfg80211 code. I wanted to
> keep as much of the monitor mode code from libertas that I could,
> mainly
>
> * priv->rtap_net_dev
> * lbs_rtap_XXX() in main.c
> * process_rxed_802_11_packet() in rx.c.
>
>
> So my code is quite simply currently:
>
> static struct cfg80211_ops lbs_cfg80211_ops = {
> // ...
> .change_virtual_intf = lbs_change_intf,
> };
>
> static int lbs_change_intf(struct wiphy *wiphy, struct net_device *dev,
> enum nl80211_iftype type, u32 *flags,
> struct vif_params *params)
> {
> struct lbs_private *priv = wiphy_priv(wiphy);
> int ret = 0;
>
> lbs_deb_enter(LBS_DEB_CFG80211);
>
> switch(type) {
> case NL80211_IFTYPE_MONITOR:
> ret = lbs_enable_monitor_mode(priv, type == NL80211_IFTYPE_MONITOR);
> if (!priv->rtap_net_dev)
> lbs_add_rtap(priv);
check what that calls -- probably register_netdev vs.
register_netdevice.
johannes