linux-toradex.git/drivers/net, branch v2.6.35.4 Linux kernel for Apalis and Colibri modules iwlwifi: fix 3945 filter flags 2010-08-26T23:46:19+00:00 Johannes Berg johannes.berg@intel.com 2010-08-17T09:24:01+00:00 637958343c8260d73a81526176286d744d90c317 commit 8b8ab9d5e352aae0dcae53c657b25ab61bb73f0f upstream. Applying the filter flags directly as done since commit 3474ad635db371b0d8d0ee40086f15d223d5b6a4 Author: Johannes Berg <johannes.berg@intel.com> Date: Thu Apr 29 04:43:05 2010 -0700 iwlwifi: apply filter flags directly broke 3945 under some unknown circumstances, as reported by Alex. Since I want to keep the direct application of filter flags on iwlagn, duplicate the code into both 3945 and agn and remove committing the RXON that broke things from the 3945 version. Reported-by: Alex Romosan <romosan@sycorax.lbl.gov> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 8b8ab9d5e352aae0dcae53c657b25ab61bb73f0f upstream.

Applying the filter flags directly as done since

commit 3474ad635db371b0d8d0ee40086f15d223d5b6a4
Author: Johannes Berg <johannes.berg@intel.com>
Date:   Thu Apr 29 04:43:05 2010 -0700

    iwlwifi: apply filter flags directly

broke 3945 under some unknown circumstances, as
reported by Alex.

Since I want to keep the direct application of
filter flags on iwlagn, duplicate the code into
both 3945 and agn and remove committing the
RXON that broke things from the 3945 version.

Reported-by: Alex Romosan <romosan@sycorax.lbl.gov>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
e1000e: don't check for alternate MAC addr on parts that don't support it 2010-08-26T23:46:19+00:00 Bruce Allan bruce.w.allan@intel.com 2010-08-19T22:48:52+00:00 654cfa23ae31350403cf3db30b4fa9fa8b5bb5e2 commit 1aef70ef125165e0114a8e475636eff242a52030 upstream. From: Bruce Allan <bruce.w.allan@intel.com> The alternate MAC address feature is only supported by 80003ES2LAN and 82571 LOMs as well as a couple 82571 mezzanine cards. Checking for an alternate MAC address on other parts can fail leading to the driver not able to load. This patch limits the check for an alternate MAC address to be done only for parts that support the feature. This issue has been around since support for the feature was introduced to the e1000e driver in 2.6.34. Signed-off-by: Bruce Allan <bruce.w.allan@intel.com> Reported-by: Fabio Varesano <fax8@users.sourceforge.net> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 1aef70ef125165e0114a8e475636eff242a52030 upstream.

From: Bruce Allan <bruce.w.allan@intel.com>

The alternate MAC address feature is only supported by 80003ES2LAN and
82571 LOMs as well as a couple 82571 mezzanine cards.  Checking for an
alternate MAC address on other parts can fail leading to the driver not
able to load.  This patch limits the check for an alternate MAC address
to be done only for parts that support the feature.

This issue has been around since support for the feature was introduced
to the e1000e driver in 2.6.34.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Reported-by: Fabio Varesano <fax8@users.sourceforge.net>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
e1000e: disable ASPM L1 on 82573 2010-08-26T23:46:19+00:00 Bruce Allan bruce.w.allan@intel.com 2010-08-19T22:48:30+00:00 d94b0aa7865743fda22297bc1d34e5e0fe6a6733 commit 19833b5dffe2f2e92a1b377f9aae9d5f32239512 upstream. On the e1000-devel mailing list, Nils Faerber reported latency issues with the 82573 LOM on a ThinkPad X60. It was found to be caused by ASPM L1; disabling it resolves the latency. The issue is present in kernels back to 2.6.34 and possibly 2.6.33. Reported-by: Nils Faerber <nils.faerber@kernelconcepts.de> Signed-off-by: Bruce Allan <bruce.w.allan@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 19833b5dffe2f2e92a1b377f9aae9d5f32239512 upstream.

On the e1000-devel mailing list, Nils Faerber reported latency issues with
the 82573 LOM on a ThinkPad X60.  It was found to be caused by ASPM L1;
disabling it resolves the latency.  The issue is present in kernels back
to 2.6.34 and possibly 2.6.33.


Reported-by: Nils Faerber <nils.faerber@kernelconcepts.de>
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
iwlagn: fix rts cts protection 2010-08-26T23:46:18+00:00 Johannes Berg johannes.berg@intel.com 2010-08-09T17:57:02+00:00 3ee378d7e0dfdb9bb342f59067d0d83cec9b766e This is a backport of mainline commit 94597ab23ea10b3bdcba534be00a9f7b35791c07. I removed the variable renamings from it and made it apply on 2.6.35. It now also incorporates some changes from commit cfecc6b492162fb49209a83dc207f182b87ea27a since those were required as well. commit 94597ab23ea10b3bdcba534be00a9f7b35791c07 upstream. Currently the driver will try to protect all frames, which leads to a lot of odd things like sending an RTS with a zeroed RA before multicast frames, which is clearly bogus. In order to fix all of this, we need to take a step back and see what we need to achieve: * we need RTS/CTS protection if requested by the AP for the BSS, mac80211 tells us this * in that case, CTS-to-self should only be enabled when mac80211 tells us * additionally, as a hardware workaround, on some devices we have to protect aggregated frames with RTS To achieve the first two items, set up the RXON accordingly and set the protection required flag in the transmit command when mac80211 requests protection for the frame. To achieve the last item, set the rate-control RTS-requested flag for all stations that we have aggregation sessions with, and set the protection required flag when sending aggregated frames (on those devices where this is required). Since otherwise bugs can occur, do not allow the user to override the RTS-for-aggregation setting from sysfs any more. Finally, also clean up the way all these flags get set in the driver and move everything into the device-specific functions. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
This is a backport of mainline commit
94597ab23ea10b3bdcba534be00a9f7b35791c07.
I removed the variable renamings from it
and made it apply on 2.6.35. It now also
incorporates some changes from commit
cfecc6b492162fb49209a83dc207f182b87ea27a
since those were required as well.
commit 94597ab23ea10b3bdcba534be00a9f7b35791c07 upstream.

Currently the driver will try to protect all frames,
which leads to a lot of odd things like sending an
RTS with a zeroed RA before multicast frames, which
is clearly bogus.

In order to fix all of this, we need to take a step
back and see what we need to achieve:
 * we need RTS/CTS protection if requested by
   the AP for the BSS, mac80211 tells us this
 * in that case, CTS-to-self should only be
   enabled when mac80211 tells us
 * additionally, as a hardware workaround, on
   some devices we have to protect aggregated
   frames with RTS

To achieve the first two items, set up the RXON
accordingly and set the protection required flag
in the transmit command when mac80211 requests
protection for the frame.

To achieve the last item, set the rate-control
RTS-requested flag for all stations that we have
aggregation sessions with, and set the protection
required flag when sending aggregated frames (on
those devices where this is required).

Since otherwise bugs can occur, do not allow the
user to override the RTS-for-aggregation setting
from sysfs any more.

Finally, also clean up the way all these flags get
set in the driver and move everything into the
device-specific functions.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ath5k: disable ASPM L0s for all cards 2010-08-26T23:45:53+00:00 Maxim Levitsky maximlevitsky@gmail.com 2010-08-13T15:27:28+00:00 18626abccb42a19a3bd6693cd5c4904d594b6c69 commit 6ccf15a1a76d2ff915cdef6ae4d12d0170087118 upstream. Atheros PCIe wireless cards handled by ath5k do require L0s disabled. For distributions shipping with CONFIG_PCIEASPM (this will be enabled by default in the future in 2.6.36) this will also mean both L1 and L0s will be disabled when a pre 1.1 PCIe device is detected. We do know L1 works correctly even for all ath5k pre 1.1 PCIe devices though but cannot currently undue the effect of a blacklist, for details you can read pcie_aspm_sanity_check() and see how it adjusts the device link capability. It may be possible in the future to implement some PCI API to allow drivers to override blacklists for pre 1.1 PCIe but for now it is best to accept that both L0s and L1 will be disabled completely for distributions shipping with CONFIG_PCIEASPM rather than having this issue present. Motivation for adding this new API will be to help with power consumption for some of these devices. Example of issues you'd see: - On the Acer Aspire One (AOA150, Atheros Communications Inc. AR5001 Wireless Network Adapter [168c:001c] (rev 01)) doesn't work well with ASPM enabled, the card will eventually stall on heavy traffic with often 'unsupported jumbo' warnings appearing. Disabling ASPM L0s in ath5k fixes these problems. - On the same card you would see a storm of RXORN interrupts even though medium is idle. Credit for root causing and fixing the bug goes to Jussi Kivilinna. Cc: David Quan <David.Quan@atheros.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Tim Gardner <tim.gardner@canonical.com> Cc: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com> Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 6ccf15a1a76d2ff915cdef6ae4d12d0170087118 upstream.

Atheros PCIe wireless cards handled by ath5k do require L0s disabled.
For distributions shipping with CONFIG_PCIEASPM (this will be enabled
by default in the future in 2.6.36) this will also mean both L1 and L0s
will be disabled when a pre 1.1 PCIe device is detected. We do know L1
works correctly even for all ath5k pre 1.1 PCIe devices though but cannot
currently undue the effect of a blacklist, for details you can read
pcie_aspm_sanity_check() and see how it adjusts the device link
capability.

It may be possible in the future to implement some PCI API to allow
drivers to override blacklists for pre 1.1 PCIe but for now it is
best to accept that both L0s and L1 will be disabled completely for
distributions shipping with CONFIG_PCIEASPM rather than having this
issue present. Motivation for adding this new API will be to help
with power consumption for some of these devices.

Example of issues you'd see:

  - On the Acer Aspire One (AOA150, Atheros Communications Inc. AR5001
    Wireless Network Adapter [168c:001c] (rev 01)) doesn't work well
    with ASPM enabled, the card will eventually stall on heavy traffic
    with often 'unsupported jumbo' warnings appearing. Disabling
    ASPM L0s in ath5k fixes these problems.

  - On the same card you would see a storm of RXORN interrupts
    even though medium is idle.

Credit for root causing and fixing the bug goes to Jussi Kivilinna.

Cc: David Quan <David.Quan@atheros.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tim Gardner <tim.gardner@canonical.com>
Cc: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ath9k_htc: fix panic on packet injection using airbase-ng tool. 2010-08-26T23:45:52+00:00 Rajkumar Manoharan rmanoharan@atheros.com 2010-08-11T14:57:43+00:00 b97ef8ac88b78b67616fa6da71889ba836b6f568 commit da93f10684bfba2983a70c10b5d417232b6a5245 upstream. This should fix the oops which occurs during the packet injection on monitor interface. EIP is at ath9k_htc_tx_start+0x69/0x220 [ath9k_htc] [<f84dc8ea>] ? invoke_tx_handlers+0xa5a/0xee0 [mac80211] [<f82c84f4>] ? ath9k_htc_tx+0x44/0xe0 [ath9k_htc] [<f84db7b8>] ? __ieee80211_tx+0xf8/0x190 [mac80211] [<f84dce0d>] ? ieee80211_tx+0x9d/0x1a0 [mac80211] [<f84dcfac>] ? ieee80211_xmit+0x9c/0x1c0 [mac80211] [<f84dd1b5>] ? ieee80211_monitor_start_xmit+0x85/0xb0 [mac80211] [<c04c30cd>] ? dev_hard_start_xmit+0x1ad/0x210 [<c04b97c2>] ? __alloc_skb+0x52/0x130 [<c04d7cd5>] ? sch_direct_xmit+0x105/0x170 [<c04c5e9f>] ? dev_queue_xmit+0x37f/0x4b0 [<c0567e1e>] ? packet_snd+0x21e/0x250 [<c05684a2>] ? packet_sendmsg+0x32/0x40 [<c04b4c63>] ? sock_aio_write+0x113/0x130 [<c0207934>] ? do_sync_write+0xc4/0x100 [<c0167740>] ? autoremove_wake_function+0x0/0x50 [<c02f4414>] ? security_file_permission+0x14/0x20 [<c0207ad4>] ? rw_verify_area+0x64/0xe0 [<c01e6458>] ? handle_mm_fault+0x338/0x390 [<c0207cd5>] ? vfs_write+0x185/0x1a0 [<c058db20>] ? do_page_fault+0x160/0x3a0 [<c0208512>] ? sys_write+0x42/0x70 [<c01033ec>] ? syscall_call+0x7/0xb Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit da93f10684bfba2983a70c10b5d417232b6a5245 upstream.

This should fix the oops which occurs during the packet injection
on monitor interface.

EIP is at ath9k_htc_tx_start+0x69/0x220 [ath9k_htc]
 [<f84dc8ea>] ? invoke_tx_handlers+0xa5a/0xee0 [mac80211]
 [<f82c84f4>] ? ath9k_htc_tx+0x44/0xe0 [ath9k_htc]
 [<f84db7b8>] ? __ieee80211_tx+0xf8/0x190 [mac80211]
 [<f84dce0d>] ? ieee80211_tx+0x9d/0x1a0 [mac80211]
 [<f84dcfac>] ? ieee80211_xmit+0x9c/0x1c0 [mac80211]
 [<f84dd1b5>] ? ieee80211_monitor_start_xmit+0x85/0xb0 [mac80211]
 [<c04c30cd>] ? dev_hard_start_xmit+0x1ad/0x210
 [<c04b97c2>] ? __alloc_skb+0x52/0x130
 [<c04d7cd5>] ? sch_direct_xmit+0x105/0x170
 [<c04c5e9f>] ? dev_queue_xmit+0x37f/0x4b0
 [<c0567e1e>] ? packet_snd+0x21e/0x250
 [<c05684a2>] ? packet_sendmsg+0x32/0x40
 [<c04b4c63>] ? sock_aio_write+0x113/0x130
 [<c0207934>] ? do_sync_write+0xc4/0x100
 [<c0167740>] ? autoremove_wake_function+0x0/0x50
 [<c02f4414>] ? security_file_permission+0x14/0x20
 [<c0207ad4>] ? rw_verify_area+0x64/0xe0
 [<c01e6458>] ? handle_mm_fault+0x338/0x390
 [<c0207cd5>] ? vfs_write+0x185/0x1a0
 [<c058db20>] ? do_page_fault+0x160/0x3a0
 [<c0208512>] ? sys_write+0x42/0x70
 [<c01033ec>] ? syscall_call+0x7/0xb

Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
wl1251: fix trigger scan timeout usage 2010-08-26T23:45:47+00:00 Yuri Kululin ext-yuri.kululin@nokia.com 2010-08-13T09:46:12+00:00 208348a42d2c5027b66e49d78ddc0548bd0193f2 commit fe0dbcc9d2e941328b3269dab102b94ad697ade5 upstream. Use appropriate command (CMD_TRIGGER_SCAN_TO) instead of scan command (CMD_SCAN) to configure trigger scan timeout. This was broken in commit 3a98c30f3e8bb1f32b5bcb74a39647b3670de275. This fix address the bug reported here: https://bugzilla.kernel.org/show_bug.cgi?id=16554 Signed-off-by: Yuri Ershov <ext-yuri.ershov@nokia.com> Signed-off-by: Yuri Kululin <ext-yuri.kululin@nokia.com> Acked-by: Kalle Valo <kvalo@adurom.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit fe0dbcc9d2e941328b3269dab102b94ad697ade5 upstream.

Use appropriate command (CMD_TRIGGER_SCAN_TO) instead of scan command
(CMD_SCAN) to configure trigger scan timeout.

This was broken in commit 3a98c30f3e8bb1f32b5bcb74a39647b3670de275.

This fix address the bug reported here:

https://bugzilla.kernel.org/show_bug.cgi?id=16554

Signed-off-by: Yuri Ershov <ext-yuri.ershov@nokia.com>
Signed-off-by: Yuri Kululin <ext-yuri.kululin@nokia.com>
Acked-by: Kalle Valo <kvalo@adurom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
smsc911x: Add spinlocks around registers access 2010-08-13T20:30:54+00:00 Catalin Marinas catalin.marinas@arm.com 2010-07-19T20:36:21+00:00 3e3c8c718ecf07b641b4d21a5d5ba259911a731b commit 492c5d943d6a04b124ba3a719dc746dc36b14cfb upstream. On SMP systems, the SMSC911x registers may be accessed by multiple CPUs and this seems to put the chip in an inconsistent state. The patch adds spinlocks to the smsc911x_reg_read, smsc911x_reg_write, smsc911x_rx_readfifo and smsc911x_tx_writefifo functions. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 492c5d943d6a04b124ba3a719dc746dc36b14cfb upstream.

On SMP systems, the SMSC911x registers may be accessed by multiple CPUs
and this seems to put the chip in an inconsistent state. The patch adds
spinlocks to the smsc911x_reg_read, smsc911x_reg_write,
smsc911x_rx_readfifo and smsc911x_tx_writefifo functions.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
e100/e1000*/igb*/ixgb*: Add missing read memory barrier 2010-08-13T20:30:49+00:00 Jeff Kirsher jeffrey.t.kirsher@intel.com 2010-08-08T16:02:31+00:00 5dd8e4f3b39adf9186d7e130a68edc43474fb9f1 commit 2d0bb1c1f4524befe9f0fcf0d0cd3081a451223f upstream. Based on patches from Sonny Rao and Milton Miller... Combined the patches to fix up clean_tx_irq and clean_rx_irq. The PowerPC architecture does not require loads to independent bytes to be ordered without adding an explicit barrier. In ixgbe_clean_rx_irq we load the status bit then load the packet data. With packet split disabled if these loads go out of order we get a stale packet, but we will notice the bad sequence numbers and drop it. The problem occurs with packet split enabled where the TCP/IP header and data are in different descriptors. If the reads go out of order we may have data that doesn't match the TCP/IP header. Since we use hardware checksumming this bad data is never verified and it makes it all the way to the application. This bug was found during stress testing and adding this barrier has been shown to fix it. The bug can manifest as a data integrity issue (bad payload data) or as a BUG in skb_pull(). This was a nasty bug to hunt down, if people agree with the fix I think it's a candidate for stable. Previously Submitted to e1000-devel only for ixgbe http://marc.info/?l=e1000-devel&m=126593062701537&w=3 We've now seen this problem hit with other device drivers (e1000e mostly) So I'm resubmitting with fixes for other Intel Device Drivers with similar issues. CC: Milton Miller <miltonm@bga.com> CC: Anton Blanchard <anton@samba.org> CC: Sonny Rao <sonnyrao@us.ibm.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 2d0bb1c1f4524befe9f0fcf0d0cd3081a451223f upstream.

Based on patches from Sonny Rao and Milton Miller...

Combined the patches to fix up clean_tx_irq and clean_rx_irq.

The PowerPC architecture does not require loads to independent bytes
to be ordered without adding an explicit barrier.

In ixgbe_clean_rx_irq we load the status bit then load the packet data.
With packet split disabled if these loads go out of order we get a
stale packet, but we will notice the bad sequence numbers and drop it.

The problem occurs with packet split enabled where the TCP/IP header
and data are in different descriptors. If the reads go out of order
we may have data that doesn't match the TCP/IP header. Since we use
hardware checksumming this bad data is never verified and it makes it
all the way to the application.

This bug was found during stress testing and adding this barrier has
been shown to fix it.  The bug can manifest as a data integrity issue
(bad payload data) or as a BUG in skb_pull().

This was a nasty bug to hunt down, if people agree with the fix I think
it's a candidate for stable.

Previously Submitted to e1000-devel only for ixgbe

http://marc.info/?l=e1000-devel&m=126593062701537&w=3

We've now seen this problem hit with other device drivers (e1000e mostly)
So I'm resubmitting with fixes for other Intel Device Drivers with
similar issues.

CC: Milton Miller <miltonm@bga.com>
CC: Anton Blanchard <anton@samba.org>
CC: Sonny Rao <sonnyrao@us.ibm.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
rtl8180: avoid potential NULL deref in rtl8180_beacon_work 2010-08-13T20:30:47+00:00 John W. Linville linville@tuxdriver.com 2010-08-05T17:46:27+00:00 d3c5501ec90af293e011b036e9c5871b300d304e commit 8f1d2d2be73a98c21e68fe2a26f633892d4abdd1 upstream. ieee80211_beacon_get can return NULL... Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 8f1d2d2be73a98c21e68fe2a26f633892d4abdd1 upstream.

ieee80211_beacon_get can return NULL...

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>