This allows drivers to request per-vif and per-sta-tid queues from which
they can pull frames. This makes it easier to keep the hardware queues
short, and to improve fairness between clients and vifs.
The task of scheduling packet transmission is left up to the driver -
queueing is controlled by mac80211. Drivers can only dequeue packets by
calling ieee80211_tx_dequeue. This makes it possible to add active queue
management later without changing drivers using this code.
This can also be used as a starting point to implement A-MSDU
aggregation in a way that does not add artificially induced latency.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[resolved minor context conflict, minor changes, endian annotations]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
of small fixes, cleanups and internal features we have:
* VHT support for TDLS and IBSS (conditional on drivers though)
* first TX performance improvements (the biggest will come later)
* many suspend/resume (race) fixes
* name_assign_type support from Tom Gundersen
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Merge tag 'mac80211-next-for-davem-2015-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg says:
====================
Lots of updates for net-next; along with the usual flurry
of small fixes, cleanups and internal features we have:
* VHT support for TDLS and IBSS (conditional on drivers though)
* first TX performance improvements (the biggest will come later)
* many suspend/resume (race) fixes
* name_assign_type support from Tom Gundersen
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to look up the RA station earlier to implement a TX
fastpath, factor out the lookup from ieee80211_build_hdr().
To always have a valid station pointer, also move some of the
checks into the new function.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Indicating just the peer's capability is fairly pointless
if the local device doesn't support it. Make the variable
track both combined, and remove the 'local support' check
in the TX path.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of looking up the destination station twice in the TX path
(first to build the header, and then for control processing), save
it when building the header and use it later in the TX path.
To avoid having to look up the station in the many callers, allow
those to pass %NULL which keeps the existing lookup.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In ieee80211_build_hdr(), the station is looked up to build the
header correctly (QoS field) and to check for authorization. For
mesh, authorization isn't checked here, and QoS capability is
mandatory, so the station lookup can be avoided.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If there's no station on the 4-addr VLAN interface, then frames
cannot be transmitted. Drop such frames earlier, before setting
up all the information for them.
We should keep the old check though since that code might be used
for other internally-generated frames.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's no need to look up the destination station twice while
building the 802.11 header for a given frame if the frame will
actually be transmitted to the station we initially looked up.
This happens for 4-addr VLAN interfaces and TDLS connections, which
both directly send the frame to the station they looked up, though
in the case of TDLS some station conditions need to be checked.
To avoid that, add a variable indicating that we've looked up the
station that the frame is going to be transmitted to, and avoid the
lookup/flag checking if it already has been done.
In the TDLS case, also move the authorized/wme_sta flag assignment
to the correct place, i.e. only when that station is really used.
Before this change, the new lookup should always have succeeded so
that the potentially erroneous data would be overwritten.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This mechanism was historic, and only ever used by IBSS, which
also doesn't need to have it as it properly manages station's
802.1X PAE state (or, with WEP, always has a key.)
Remove the mechanism to clean up the code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The ieee80211_tx_prepare_skb() function currently entirely ignores
the fact that the SKB that is passed in might be split into more
than one due to fragmentation and doesn't check the list of skbs
that the TX handlers may create. In case this happens, it would
leak them.
Fix this and also don't leave the skb next/prev pointers dangling
pointing to the on-stack sk_buff_head.
Reported-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Revert commit ad38bfc916 ("mac80211: Tx frame latency statistics")
(along with some follow-up fixes).
This code turned out not to be as useful in the current form as we
thought, and we've internally hacked it up more, but that's not
very suitable for upstream (for now), and we might just do that
with tracing instead.
Therefore, for now at least, remove this code. We might also need
to use the skb->tstamp field for the TCP performance issue, which
is more important than the debugging.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since multicast addresses don't exist as stations, don't attempt
to look them up in the hashtable on TX.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The current minstrel_ht rate control behavior is somewhat optimistic in
trying to find optimum TX rate. While this is usually fine for normal
Data frames, there are cases where a more conservative set of retry
parameters would be beneficial to make the connection more robust.
EAPOL frames are critical to the authentication and especially the
EAPOL-Key message 4/4 (the last message in the 4-way handshake) is
important to get through to the AP. If that message is lost, the only
recovery mechanism in many cases is to reassociate with the AP and start
from scratch. This can often be avoided by trying to send the frame with
more conservative rate and/or with more link layer retries.
In most cases, minstrel_ht is currently using the initial EAPOL-Key
frames for probing higher rates and this results in only five link layer
transmission attempts (one at high(ish) MCS and four at MCS0). While
this works with most APs, it looks like there are some deployed APs that
may have issues with the EAPOL frames using HT MCS immediately after
association. Similarly, there may be issues in cases where the signal
strength or radio environment is not good enough to be able to get
frames through even at couple of MCS 0 tries.
The best approach for this would likely to be to reduce the TX rate for
the last rate (3rd rate parameter in the set) to a low basic rate (say,
6 Mbps on 5 GHz and 2 or 5.5 Mbps on 2.4 GHz), but doing that cleanly
requires some more effort. For now, we can start with a simple one-liner
that forces the minimum rate to be used for EAPOL frames similarly how
the TX rate is selected for the IEEE 802.11 Management frames. This does
result in a small extra latency added to the cases where the AP would be
able to receive the higher rate, but taken into account how small number
of EAPOL frames are used, this is likely to be insignificant. A future
optimization in the minstrel_ht design can also allow this patch to be
reverted to get back to the more optimized initial TX rate.
It should also be noted that many drivers that do not use minstrel as
the rate control algorithm are already doing similar workarounds by
forcing the lowest TX rate to be used for EAPOL frames.
Cc: stable@vger.kernel.org
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure BIP-GMAC-128 and BIP-GMAC-256 to the
driver and also use software-implementation within mac80211 when the
driver does not support this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure BIP-CMAC-256 to the driver and also
use software-implementation within mac80211 when the driver does not
support this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure CCMP-256 to the driver and also use
software-implementation within mac80211 when the driver does not support
this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[squash ccmp256 -> mic_len argument change]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows mac80211 to configure GCMP and GCMP-256 to the driver and
also use software-implementation within mac80211 when the driver does
not support this with hardware accelaration.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
[remove a spurious newline]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When roaming / suspending, it makes no sense to wait until
the transmit queues of the device are empty. In extreme
condition they can be starved (VO saturating the air), but
even in regular cases, it is pointless to delay the roaming
because the low level driver is trying to send packets to
an AP which is far away. We'd rather drop these packets and
let TCP retransmit if needed. This will allow to speed up
the roaming.
For suspend, the explanation is even more trivial.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Implement the new counters cfg80211 can now advertise to userspace.
The TX code is in the sequence number handler, which is a bit odd,
but that place already knows the TID and frame type, so it was
easiest and least impact there.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fixes a crash on attempting to calculate the frame duration for a VHT
packet (which needs to be handled by hw/driver instead).
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Allow drivers to support NL80211_SCAN_FLAG_RANDOM_ADDR with software
based scanning and generate a random MAC address for them for every
scan request with the flag.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In TDLS (e.g., TDLS off-channel) there is a requirement for
some drivers to supply an unused TID between the AP and the
device to the FW, to allow sending PTI requests and to allow
the FW to aggregate on a specific TID for better throughput.
To ensure that the allocated TID is indeed unused, this patch
introduces an API for blocking the driver from TXing on that
TID.
Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
For some TDLS channel switch implementations data frames need to be
sent by the firmware based on a template. This template should be
created by mac80211, and thus needs to properly be built from an
802.3 frame into an 802.11 frame. In addition, the device will need
the key information so the select_key handler needs to be run.
However, the driver/device will be responsible for all of the crypto
encapsulation, as the sequence numbers etc. cannot be built by the
host anyway in this case since it's a template to be used multiple
times.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Factor out the 802.11 header building code from the xmit function
to be able to use it separately in a later commit.
While at it, fix up some documentation.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of passing the band as a parameter to ieee80211_xmit()
and ieee80211_tx(), move it outside of the two functions while
making sure info->band is set up before calling them.
This removes the parameter and simplifies the follow commit.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Allows setting of an skb's flags - if needed - when calling
ieee80211_subif_start_xmit().
Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This patch adds 802.11p OCB (Outside the Context of a BSS) mode
support.
When communicating in OCB mode a mandatory wildcard BSSID
(48 '1' bits) is used.
The EDCA parameters handling function was changed to support
802.11p specific values.
The insertion of a newly discovered STAs is done in the similar way
as in the IBSS mode -- through the deferred insertion.
The OCB mode uses a periodic 'housekeeping task' for expiration of
disconnected STAs (in the similar manner as in the MESH mode).
New Kconfig option for verbose OCB debugging outputs is added.
Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
John W. Linville says:
====================
pull request: wireless-next 2014-09-22
Please pull this batch of updates intended for the 3.18 stream...
For the mac80211 bits, Johannes says:
"This time, I have some rate minstrel improvements, support for a very
small feature from CCX that Steinar reverse-engineered, dynamic ACK
timeout support, a number of changes for TDLS, early support for radio
resource measurement and many fixes. Also, I'm changing a number of
places to clear key memory when it's freed and Intel claims copyright
for code they developed."
For the bluetooth bits, Johan says:
"Here are some more patches intended for 3.18. Most of them are cleanups
or fixes for SMP. The only exception is a fix for BR/EDR L2CAP fixed
channels which should now work better together with the L2CAP
information request procedure."
For the iwlwifi bits, Emmanuel says:
"I fix here dvm which was broken by my last pull request. Arik
continues to work on TDLS and Luca solved a few issues in CT-Kill. Eyal
keeps digging into rate scaling code, more to come soon. Besides this,
nothing really special here."
Beyond that, there are the usual big batches of updates to ath9k, b43,
mwifiex, and wil6210 as well as a handful of other bits here and there.
Also, rtlwifi gets some btcoexist attention from Larry.
Please let me know if there are problems!
====================
Had to adjust the wil6210 code to comply with Joe Perches's recent
change in net-next to make the netdev_*() routines return void instead
of 'int'.
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a possible issue with the use, or lack thereof of sk_refcnt and
sk_wmem_alloc in the wifi ack status functionality.
Specifically if a socket were to request acknowledgements, and the socket
were to have sk_refcnt drop to 0 resulting in it waiting on sk_wmem_alloc
to reach 0 it would be possible to have sock_queue_err_skb orphan the last
buffer, resulting in __sk_free being called on the socket. After this the
buffer is enqueued on sk_error_queue, however the queue has already been
flushed resulting in at least a memory leak, if not a data corruption.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function description claimed that on error the skb isn't
freed even though it is, and stated return values that are
different than what really happens in the code.
Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Our legal structure changed at some point (see wikipedia), but
we forgot to immediately switch over to the new copyright
notice.
For files that we have modified in the time since the change,
add the proper copyright notice now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Header-less cloned skbs with sufficient headroom need not be cloned
unless the tailroom is going to be modified.
Fix ieee80211_skb_resize so it would only resize cloned skbs if either
the header isn't released or the tailroom is going to be modified.
Some drivers might have assumed that skbs are never cloned, so add a HW
flag that explicitly permits cloned TX skbs. Drivers which do not modify
TX skbs should set this flag to avoid copying skbs.
Signed-off-by: Ido Yariv <idox.yariv@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We currently track the QoS capability twice: for all peer stations
in the WLAN_STA_WME flag, and for any clients associated to an AP
interface separately for drivers in the sta->sta.wme field.
Remove the WLAN_STA_WME flag and track the capability only in the
driver-visible field, getting rid of the limitation that the field
is only valid in AP mode.
Reviewed-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This reverts commit 277d916fc2 as it was
at least breaking iwlwifi by setting the IEEE80211_TX_CTL_NO_PS_BUFFER
flag in all kinds of interface modes, not only for AP mode where it is
appropriate.
To avoid reintroducing the original problem, explicitly check for probe
request frames in the multicast buffering code.
Cc: stable@vger.kernel.org
Fixes: 277d916fc2 ("mac80211: move "bufferable MMPDU" check to fix AP mode scan")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Rename the flags used in the Tx path and add an explanation for the
reasons to drop, send directly or through the AP.
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Sometimes different vifs may be stopping the queues for the same
reason (e.g. when several interfaces are performing a channel switch).
Instead of using a bitmask for the reasons, use an integer that holds
a refcount instead. In order to keep it backwards compatible,
introduce a boolean in some functions that tell us whether the queue
stopping should be refcounted or not. For now, use not refcounted for
all calls to keep it functionally the same as before.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Converting time from one format to another seems to give coders a warm
and fuzzy feeling.
Use the proper interfaces.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John W. Linville <linville@tuxdriver.com>
[fix compile error]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
vif->csa_active is protected by mutexes only. This
means it is unreliable to depend on it on codeflow
in non-sleepable beacon and CSA code. There was no
guarantee to have vif->csa_active update be
visible before beacons are updated on SMP systems.
Using csa counter offsets which are embedded in
beacon struct (and thus are protected with single
RCU assignment) is much safer.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Having csa counters part of beacon and probe_resp
structures makes it easier to get rid of possible
races between setting a beacon and updating
counters on SMP systems by guaranteeing counters
are always consistent against given beacon struct.
While at it relax WARN_ON into WARN_ON_ONCE to
prevent spamming logs and racing.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
[remove pointless array check]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Allow send frames using monitor interface
when DFS chandef and we pass CAC (beaconing
allowed).
This fix problem when old kernel and new backports used,
in such case hostapd create/use also monitor interface.
Before this patch all frames hostapd send using monitor
iface were dropped when AP was configured on DFS channel.
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
It is currently possible to have a race due to the station PS
unblock work like this:
* station goes to sleep with frames buffered in the driver
* driver blocks wakeup
* station wakes up again
* driver flushes/returns frames, and unblocks, which schedules
the unblock work
* unblock work starts to run, and checks that the station is
awake (i.e. that the WLAN_STA_PS_STA flag isn't set)
* we process a received frame with PM=1, setting the flag again
* ieee80211_sta_ps_deliver_wakeup() runs, delivering all frames
to the driver, and then clearing the WLAN_STA_PS_DRIVER and
WLAN_STA_PS_STA flags
In this scenario, mac80211 will think that the station is awake,
while it really is asleep, and any TX'ed frames should be filtered
by the device (it will know that the station is sleeping) but then
passed to mac80211 again, which will not buffer it either as it
thinks the station is awake, and eventually the packets will be
dropped.
Fix this by moving the clearing of the flags to exactly where we
learn about the situation. This creates a problem of reordering,
so introduce another flag indicating that delivery is being done,
this new flag also queues frames and is cleared only while the
spinlock is held (which the queuing code also holds) so that any
concurrent delivery/TX is handled correctly.
Reported-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Make the beacon CSA counters part of ieee80211_mutable_offsets and don't
decrement CSA counters when generating a beacon template. This permits the
driver to offload the CSA counters handling. Since mac80211 updates the probe
responses with the correct counter, the driver should sync the counter's value
with mac80211 using ieee80211_csa_update_counter function.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Add a new API ieee80211_beacon_get_template, which doesn't
affect DTIM counter and should be used if the device generates beacon
frames, and new beacon template is needed. In addition set the offsets
to TIM IE for MESH interface.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Support up to IEEE80211_MAX_CSA_COUNTERS_NUM csa counters.
This is defined to be 2 now, to support both CSA and eCSA
counters.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Track current csa counter value and use it
to update mgmt frames at the provided offsets.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
commit de74a1d903
"mac80211: fix WPA with VLAN on AP side with ps-sta"
fixed an issue where queued multicast packets would
be sent out encrypted with the key of an other bss.
commit "7cbf9d017dbb5e3276de7d527925d42d4c11e732"
"mac80211: fix oops on mesh PS broadcast forwarding"
essentially reverted it, because vif.type cannot be AP_VLAN
due to the check to vif.type in ieee80211_get_buffered_bc before.
As the later commit intended to fix the MESH case, fix it
by checking for IFTYPE_AP instead of IFTYPE_AP_VLAN.
Cc: stable@vger.kernel.org
Fixes: 7cbf9d017d ("mac80211: fix oops on mesh PS broadcast forwarding")
Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There is a race between the TX path and the STA wakeup: while
a station is sleeping, mac80211 buffers frames until it wakes
up, then the frames are transmitted. However, the RX and TX
path are concurrent, so the packet indicating wakeup can be
processed while a packet is being transmitted.
This can lead to a situation where the buffered frames list
is emptied on the one side, while a frame is being added on
the other side, as the station is still seen as sleeping in
the TX path.
As a result, the newly added frame will not be send anytime
soon. It might be sent much later (and out of order) when the
station goes to sleep and wakes up the next time.
Additionally, it can lead to the crash below.
Fix all this by synchronising both paths with a new lock.
Both path are not fastpath since they handle PS situations.
In a later patch we'll remove the extra skb queue locks to
reduce locking overhead.
BUG: unable to handle kernel
NULL pointer dereference at 000000b0
IP: [<ff6f1791>] ieee80211_report_used_skb+0x11/0x3e0 [mac80211]
*pde = 00000000
Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
EIP: 0060:[<ff6f1791>] EFLAGS: 00210282 CPU: 1
EIP is at ieee80211_report_used_skb+0x11/0x3e0 [mac80211]
EAX: e5900da0 EBX: 00000000 ECX: 00000001 EDX: 00000000
ESI: e41d00c0 EDI: e5900da0 EBP: ebe458e4 ESP: ebe458b0
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 000000b0 CR3: 25a78000 CR4: 000407d0
DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
DR6: ffff0ff0 DR7: 00000400
Process iperf (pid: 3934, ti=ebe44000 task=e757c0b0 task.ti=ebe44000)
iwlwifi 0000:02:00.0: I iwl_pcie_enqueue_hcmd Sending command LQ_CMD (#4e), seq: 0x0903, 92 bytes at 3[3]:9
Stack:
e403b32c ebe458c4 00200002 00200286 e403b338 ebe458cc c10960bb e5900da0
ff76a6ec ebe458d8 00000000 e41d00c0 e5900da0 ebe458f0 ff6f1b75 e403b210
ebe4598c ff723dc1 00000000 ff76a6ec e597c978 e403b758 00000002 00000002
Call Trace:
[<ff6f1b75>] ieee80211_free_txskb+0x15/0x20 [mac80211]
[<ff723dc1>] invoke_tx_handlers+0x1661/0x1780 [mac80211]
[<ff7248a5>] ieee80211_tx+0x75/0x100 [mac80211]
[<ff7249bf>] ieee80211_xmit+0x8f/0xc0 [mac80211]
[<ff72550e>] ieee80211_subif_start_xmit+0x4fe/0xe20 [mac80211]
[<c149ef70>] dev_hard_start_xmit+0x450/0x950
[<c14b9aa9>] sch_direct_xmit+0xa9/0x250
[<c14b9c9b>] __qdisc_run+0x4b/0x150
[<c149f732>] dev_queue_xmit+0x2c2/0xca0
Cc: stable@vger.kernel.org
Reported-by: Yaara Rozenblum <yaara.rozenblum@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: Stanislaw Gruszka <sgruszka@redhat.com>
[reword commit log, use a separate lock]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
