linux-toradex.git/net/mac80211/main.c, branch v3.0.44

mac80211: Fix a rwlock bad magic bug

2012-03-01T00:33:40+00:00

commit b57e6b560fc2a2742910ac5ca0eb2c46e45aeac2 upstream.

read_lock(&tpt_trig->trig.leddev_list_lock) is accessed via the path
ieee80211_open (->) ieee80211_do_open (->) ieee80211_mod_tpt_led_trig
(->) ieee80211_start_tpt_led_trig (->) tpt_trig_timer before initializing
it.
the intilization of this read/write lock happens via the path
ieee80211_led_init (->) led_trigger_register, but we are doing
'ieee80211_led_init'  after 'ieeee80211_if_add' where we
register netdev_ops.
so we access leddev_list_lock before initializing it and causes the
following bug in chrome laptops with AR928X cards with the following
script

while true
do
sudo modprobe -v ath9k
sleep 3
sudo modprobe -r ath9k
sleep 3
done

	BUG: rwlock bad magic on CPU#1, wpa_supplicant/358, f5b9eccc
	Pid: 358, comm: wpa_supplicant Not tainted 3.0.13 #1
	Call Trace:

	[<8137b9df>] rwlock_bug+0x3d/0x47
	[<81179830>] do_raw_read_lock+0x19/0x29
	[<8137f063>] _raw_read_lock+0xd/0xf
	[] tpt_trig_timer+0xc3/0x145 [mac80211]
	[] ieee80211_mod_tpt_led_trig+0x152/0x174 [mac80211]
	[] ieee80211_do_open+0x11e/0x42e [mac80211]
	[] ? ieee80211_check_concurrent_iface+0x26/0x13c [mac80211]
	[] ieee80211_open+0x48/0x4c [mac80211]
	[<812dbed8>] __dev_open+0x82/0xab
	[<812dc0c9>] __dev_change_flags+0x9c/0x113
	[<812dc1ae>] dev_change_flags+0x18/0x44
	[<8132144f>] devinet_ioctl+0x243/0x51a
	[<81321ba9>] inet_ioctl+0x93/0xac
	[<812cc951>] sock_ioctl+0x1c6/0x1ea
	[<812cc78b>] ? might_fault+0x20/0x20
	[<810b1ebb>] do_vfs_ioctl+0x46e/0x4a2
	[<810a6ebb>] ? fget_light+0x2f/0x70
	[<812ce549>] ? sys_recvmsg+0x3e/0x48
	[<810b1f35>] sys_ioctl+0x46/0x69
	[<8137fa77>] sysenter_do_call+0x12/0x2

Cc: Gary Morain 
Cc: Paul Stewart 
Cc: Abhijit Pradhan 
Cc: Vasanthakumar Thiagarajan 
Cc: Rajkumar Manoharan 
Acked-by: Johannes Berg 
Tested-by: Mohammed Shafi Shajakhan 
Signed-off-by: Mohammed Shafi Shajakhan 
Signed-off-by: John W. Linville 
Signed-off-by: Greg Kroah-Hartman

mac80211: add missing rcu_barrier

2011-05-16T18:25:29+00:00

mac80211 uses call_rcu() with functions that are
defined in the module, so it must use rcu_barrier()
at module exit time.

Luckily, this seems to not be a problem in practice
as module unload and unregistration takes a long
time and probably does multiple synchronize_rcu().

Signed-off-by: Johannes Berg 
Signed-off-by: John W. Linville

mac80211: verify IBSS in interface combinations

2011-05-16T18:25:28+00:00

Drivers shouldn't attempt to advertise support
for more than one IBSS interface since mac80211
doesn't support that. Check and return an error
from ieee80211_register_hw() in that case.

Signed-off-by: Johannes Berg 
Signed-off-by: John W. Linville

mac80211: sparse RCU annotations

2011-05-16T18:10:41+00:00

This adds sparse RCU annotations to most of
mac80211, only the mesh code remains to be
done.

Due the the previous patches, the annotations
are pretty simple. The only thing that this
actually changes is removing the RCU usage of
key->sta in debugfs since this pointer isn't
actually an RCU-managed pointer (it only has
a single assignment done before the key even
goes live). As that is otherwise harmless, I
decided to make it part of this patch.

Signed-off-by: Johannes Berg 
Signed-off-by: John W. Linville

cfg80211: advertise possible interface combinations

2011-05-16T18:10:40+00:00

Add the ability to advertise interface combinations in nl80211.
This allows the driver to indicate what the combinations are
that it supports. "Combinations" of just a single interface are
implicit, as previously. Note that cfg80211 will enforce that
the restrictions are met, but not for all drivers yet (once all
drivers are updated, we can remove the flag and enforce for all).

When no combinations are actually supported, an empty list will
be exported so that userspace can know if the kernel exported
this info or not (although it isn't clear to me what tools using
the info should do if the kernel didn't export it).

Since some interface types are purely virtual/software and don't
fit the restrictions, those are exposed in a new list of pure SW
types, not subject to restrictions. This mainly exists to handle
AP-VLAN and monitor interfaces in mac80211.

Signed-off-by: Johannes Berg 
Signed-off-by: John W. Linville

cfg80211/mac80211: avoid bounce back mac->cfg->mac on sched_scan_stopped

2011-05-12T18:10:55+00:00

When sched_scan_stopped was called by the driver, mac80211 calls
cfg80211, which in turn was calling mac80211 back with a flag
"driver_initiated".  This flag was used so that mac80211 would do the
necessary cleanup but would not call the driver.  This was enough to
prevent the bounce back between the driver and mac80211, but not
between mac80211 and cfg80211.

To fix this, we now do the cleanup in mac80211 before calling
cfg80211.  To help with locking issues, the workqueue was moved from
cfg80211 to mac80211.

Reported-by: Johannes Berg 
Signed-off-by: Luciano Coelho 
Signed-off-by: John W. Linville

mac80211: add support for HW scheduled scan

2011-05-11T19:12:27+00:00

Implement support for HW scheduled scan.  The mac80211 code doesn't perform
scheduled scans itself, but calls the driver to start and stop scheduled
scans.

This patch also creates a trace event class to be used by drv_hw_scan
and the new drv_sched_scan_start and drv_sched_stop functions, in
order to avoid duplicate code.

Signed-off-by: Luciano Coelho 
Signed-off-by: John W. Linville

mac80211: Fix build error when CONFIG_PM is not defined

2011-05-10T19:54:44+00:00

When mac80211 is built without CONFIG_PM being defined, the following errors
are output:

net/mac80211/main.c: In function ‘ieee80211_register_hw’:
net/mac80211/main.c:700: error: ‘const struct ieee80211_ops’ has no member named ‘suspend’
net/mac80211/main.c:700: error: ‘const struct ieee80211_ops’ has no member named ‘resume’
make[2]: *** [net/mac80211/main.o] Error 1
make[1]: *** [net/mac80211] Error 2
make[1]: *** Waiting for unfinished jobs....
make: *** [net] Error 2

Signed-off-by: Larry Finger 
Signed-off-by: John W. Linville

mac80211: add basic support for WoWLAN

2011-05-05T18:59:20+00:00

This adds basic support for the new WoWLAN
configuration in mac80211. The behaviour is
completely offloaded to the driver though,
with two new callbacks (suspend/resume).

Options for the driver include a complete
reconfiguration after wakeup, and exposing
all the triggers it wants to support.

Signed-off-by: Johannes Berg 
Signed-off-by: John W. Linville

cfg80211: Remove unused wiphy flag

2011-05-05T18:59:17+00:00

The only user of WIPHY_FLAG_SUPPORTS_SEPARATE_DEFAULT_KEYS was removed
and consequently, this flag can be removed, too. In addition, a single
capability flag was not enough to indicate this capability clearly since
the device behavior may be different based on which operating mode is
being used.

Signed-off-by: Jouni Malinen 
Signed-off-by: John W. Linville