Currently DFS works under assumption there could be only one channel
context in the hardware. Hence, drivers just calls the function
ieee80211_radar_detected() passing the hardware structure. However, with
MLO, this obviously will not work since number of channel contexts will be
more than one and hence drivers would need to pass the channel information
as well on which the radar is detected.
Also, when radar is detected in one of the links, other link's CAC should
not be cancelled.
Hence, in order to support DFS with MLO, do the following changes -
* Add channel context conf pointer as an argument to the function
ieee80211_radar_detected(). During MLO, drivers would have to pass on
which channel context conf radar is detected. Otherwise, drivers could
just pass NULL.
* ieee80211_radar_detected() will iterate over all channel contexts
present and
* if channel context conf is passed, only mark that as radar
detected
* if NULL is passed, then mark all channel contexts as radar
detected
* Then as usual, schedule the radar detected work.
* In the worker, go over all the contexts again and for all such context
which is marked with radar detected, cancel the ongoing CAC by calling
ieee80211_dfs_cac_cancel() and then notify cfg80211 via
cfg80211_radar_event().
* To cancel the CAC, pass the channel context as well where radar is
detected to ieee80211_dfs_cac_cancel(). This ensures that CAC is
canceled only on the links using the provided context, leaving other
links unaffected.
This would also help in scenarios where there is split phy 5 GHz radio,
which is capable of DFS channels in both lower and upper band. In this
case, simultaneous radars can be detected.
Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Link: https://patch.msgid.link/20240906064426.2101315-9-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There are a number of places where RCU list iteration is
used, but that aren't (always) called with RCU held. Use
just list_for_each_entry() in most, and annotate iface
iteration with the required locks.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20240827094939.ed8ac0b2f897.I8443c9c3c0f8051841353491dae758021b53115e@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When updating a channel context, the code can apply wider
bandwidth TDLS STA channel definitions to each and every
channel context used by the device, an approach that will
surely lead to problems if there is ever more than one.
Restrict the wider BW TDLS STA consideration to only TDLS
STAs that are actually related to links using the channel
context being updated.
Fixes: 0fabfaafec ("mac80211: upgrade BW of TDLS peers when possible")
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20240612143707.1ad989acecde.I5c75c94d95c3f4ea84f8ff4253189f4b13bad5c3@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In channel switch without an additional channel context,
where the reassign logic kicks in, we also need to update
the station bandwidth and chandef minimum width correctly
to avoid having station rate control configured to wider
bandwidth than the channel context. Do that now.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20240612143418.0bc3d28231b3.I51e76df86212057ca0469e235ba9bf4461cbee75@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Make ieee80211_chan_bw_change() able to use the reserved chanreq
(really the chandef part of it) for the calculations, so it can
be used _without_ applying the changes first. Remove the comment
that indicates this is required, since it no longer is. However,
this capability only gets used later.
Also, this is not ideal, we really should not different so much
between reserved and non-reserved usage, to simplify. That's a
further cleanup later though.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://patch.msgid.link/20240612143418.1a08cf83b8cb.Ie567bb272eb25ce487651088f13ad041f549651c@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Collect the CSA data in ieee80211_link_data_managed and
ieee80211_link_data into a csa sub-struct to clean up a
bit and make adding new things more obvious.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240506215543.29f954b1f576.I9a683a9647c33d4dd3011aade6677982428c1082@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In the unlikely event that link_use_channel fails while activating a
link, mac80211 would go into a bad state. Unfortunately, we cannot
completely avoid failures from drivers in this case.
However, what we can do is to just continue internally anyway and assume
the driver is going to trigger a recovery flow from its side. Doing that
means that we at least have a consistent state in mac80211 allowing such
a recovery flow to succeed.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240418115219.1129e89f4b55.I6299678353e50e88b55c99b0bce15c64b52c2804@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's no need for a label/goto here, the only thing is
that drv_assign_vif_chanctx() must succeed to set 'conf'
and add the new context to the list, the remaining code
is (and must be) the same regardless.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240418115219.a94852030d33.I9d647178ab25636372ed79e5312c68a06e0bf60c@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When searching for a chanctx for re-use, it's later adjusted and
assigned. It may also be that another one is already assigned to
the link in question, so unassign can also happen. In short, the
driver is called multiple times. During these callbacks, it may
thus change active links (on another interface), which then can
in turn cause the found chanctx (that's going to be reused) to
get removed and freed.
To avoid this, temporarily assign it to the reserved chanctx and
track the link that wants to use it in the reserved_links list.
This causes the ieee80211_chanctx_refcount() to be increased by
one during these operations, thus avoiding the free.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240418115219.94ea84c8ee1e.I0b247dbc0cd937ae6367bc0fc7e8d156b5d5f9b1@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The vif's idle state doesn't automatically go to true when
any link removes the channel context, it's only idle when
_all_ links no longer have a channel context. Fix that.
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240418105220.90df97557702.I05d2228ce85c203b9f2d6da8538cc16dce46752a@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When doing link switch with a disjoint set of links before
and after the switch, we end up removing all channel contexts,
adding new ones later. This looks like 'idle' to the code now,
and we enter idle which also includes flushing queues. But we
can't actually flush since we don't have a link active (bound
to a channel context), and entering idle just to leave it again
is also wrong.
Fix this by passing through an indication that we shouldn't do
any idle checks in this case.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240320091155.170328bac555.If4a522a9dd3133b91983854b909a4de13aa635da@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We sometimes need to check if a link is active, and this
is complicated by the fact that active_links has no bits
set when the vif isn't (acting as) an MLD. Add a small
new helper ieee80211_vif_link_active() to make that a bit
easier, and use it in a few places.
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240228094901.688760aff5f7.I06892a503f5ecb9563fbd678d35d08daf7a044b0@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Aloka originally suggested that puncturing should be part of
the chandef, so that it's treated correctly. At the time, I
disagreed and it ended up not part of the chandef, but I've
now realized that this was wrong. Even for clients, the RX,
and perhaps more importantly, CCA configuration needs to take
puncturing into account.
Move puncturing into the chandef, and adjust all the code
accordingly. Also add a few tests for puncturing in chandef
compatibility checking.
Link: https://lore.kernel.org/linux-wireless/20220214223051.3610-1-quic_alokad@quicinc.com/
Suggested-by: Aloka Dixit <quic_alokad@quicinc.com>
Link: https://msgid.link/20240129194108.307183a5d2e5.I4d7fe2f126b2366c1312010e2900dfb2abffa0f6@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
EHT requires that stations are able to participate in
wider bandwidth OFDMA, i.e. parse downlink OFDMA and
uplink OFDMA triggers when they're not capable of (or
not connected at) the (wider) bandwidth that the AP
is using. This requires hardware configuration, since
the entity responsible for parsing (possibly hardware)
needs to know the AP bandwidth.
To support this, change the channel request to have
the AP's bandwidth for clients, and track that in the
channel context in mac80211. This means that the same
chandef might need to be split up into two different
contexts, if the APs are different. Interfaces other
than client are not participating in OFDMA the same
way, so they don't request any AP setting.
Note that this doesn't introduce any API to split a
channel context, so that there are cases where this
might lead to a disconnect, e.g. if there are two
client interfaces using the same channel context, e.g.
both 160 MHz connected to different 320 MHz APs, and
one of the APs switches to 160 MHz.
Note also there are possible cases where this can be
optimised, e.g. when using the upper or lower 160 Mhz,
but I haven't been able to really fully understand the
spec and/or hardware limitations.
If, for some reason, there are no hardware limits on
this because the OFDMA (downlink/trigger) parsing is
done in firmware and can take the transmitter into
account, then drivers can set the new flag
IEEE80211_VIF_IGNORE_OFDMA_WIDER_BW on interfaces to
not have them request any AP bandwidth in the channel
context and ignore this issue entirely. The bss_conf
still contains the AP configuration (if any, i.e. EHT)
in the chanreq.
Link: https://msgid.link/20240129194108.d3d5b35dd783.I939d04674f4ff06f39934b1591c8d36a30ce74c2@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In the channel context code we have quite a few instances
of nested loops iterating the interfaces and then links.
Add a new for_each_sdata_link() macro and use it. Also,
since it's easier, convert all the loops and a few other
places away from RCU as we now hold the wiphy mutex
everywhere anyway.
This does cause a little bit more work (such as checking
interface types for each link of an interface rather than
not iterating links in some cases), but that's not a huge
issue and seems like an acceptable trade-off, readability
is important too.
Link: https://msgid.link/20240129194108.7240829bd96d.I5ccbb8dd019cbcb5326c85d76121359225d6541a@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
For channel contexts, mac80211 currently uses the cfg80211
chandef struct (control channel, center freq(s), width) to
define towards drivers and internally how these behave. In
fact, there are _two_ such structs used, where the min_def
can reduce bandwidth according to the stations connected.
Unfortunately, with EHT this is longer be sufficient, at
least not for all hardware. EHT requires that non-AP STAs
that are connected to an AP with a lower bandwidth than it
(the AP) advertises (e.g. 160 MHz STA connected to 320 MHz
AP) still be able to receive downlink OFDMA and respond to
trigger frames for uplink OFDMA that specify the position
and bandwidth for the non-AP STA relative to the channel
the AP is using. Therefore, they need to be aware of this,
and at least for some hardware (e.g. Intel) this awareness
is in the hardware. As a result, use of the "same" channel
may need to be split over two channel contexts where they
differ by the AP being used.
As a first step, introduce a concept of a channel request
('chanreq') for each interface, to control the context it
requests. This step does nothing but reorganise the code,
so that later the AP's chandef can be added to the request
in order to handle the EHT case described above.
Link: https://msgid.link/20240129194108.2e88e48bd2e9.I4256183debe975c5ed71621611206fdbb69ba330@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There are still surprisingly many non-chanctx drivers, but in
mac80211 that code is a bit awkward. Simplify this by having
those drivers assign 'emulated' ops, so that the mac80211 code
can be more unified between non-chanctx/chanctx drivers. This
cuts the number of places caring about it by about 15, which
are scattered across - now they're fewer and no longer in the
channel context handling.
Link: https://msgid.link/20240129194108.6d0ead50f5cf.I60d093b2fc81ca1853925a4d0ac3a2337d5baa5b@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Rewrite the station-side connection handling. The connection
flags (IEEE80211_DISABLE_*) are rather confusing, and they're
not always maintained well. Additionally, for wider-bandwidth
OFDMA support we need to know the precise bandwidth of the AP,
which is currently somewhat difficult.
Rewrite this to have a 'mode' (S1G/legacy/HT/...) and a limit
on the bandwidth. This is not entirely clean because some of
those modes aren't completely sequenced (as this assumes in
some places), e.g. VHT doesn't exist on 2.4 GHz, but HE does.
However, it still simplifies things and gives us a good idea
what we're operating as, so we can parse elements accordingly
etc.
This leaves a FIXME for puncturing, this is addressed in a
later patch.
Reviewed-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240129194108.9451722c0110.I3e61f4cfe9da89008e1854160093c76a1e69dc2a@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
ENOTSUP isn't a standard error code. EOPNOTSUPP should be used instead.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Reviewed-by: Gregory Greenman <gregory.greenman@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20231211085121.3841b71c867d.Idf2ad01d9dfe8d6d6c352bf02deb06e49701ad1d@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
To support the WBRF mechanism, Wifi adapters utilized in the system must
register the frequencies in use (or unregister those frequencies no longer
used) via the dedicated calls. So that, other drivers responding to the
frequencies can take proper actions to mitigate possible interference.
Co-developed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Co-developed-by: Evan Quan <quanliangl@hotmail.com>
Signed-off-by: Evan Quan <quanliangl@hotmail.com>
Signed-off-by: Ma Jun <Jun.Ma2@amd.com>
Link: https://msgid.link/20231211100630.2170152-5-Jun.Ma2@amd.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the local->mtx, so we don't need this mutex any
more. Remove it.
Most of this change was done automatically with spatch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We now hold the wiphy mutex everywhere that we use or
needed the chanctx_mtx, so we don't need this mutex any
more. Remove it.
Most of this change was done automatically with spatch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This work should be made per link as well, and then
will have cancellation issues. Moving it to a wiphy
work already fixes those beforehand.
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Add NULL check for compat variable to avoid crash in
cfg80211_chandef_compatible() if it got called with
some mixed up channel context where not all the users
compatible with each other, which shouldn't happen.
Signed-off-by: Anjaneyulu <pagadala.yesu.anjaneyulu@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230616094948.ae0f10dfd36b.Iea98c74aeb87bf6ef49f6d0c8687bba0dbea2abd@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Channel switch obviously must be handled per link, and we
have a (potential) deadlock when canceling that work. Use
the new delayed wiphy work to handle this instead and get
rid of the explicit timer that way too.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There are a number of upcoming things in both the stack and
drivers that would otherwise conflict, so merge wireless to
wireless-next to be able to avoid those conflicts.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When we allocate a new channel context, or find an existing one
that is compatible, we currently assign it to a link before its
mindef is updated. This leads to strange situations, especially
in link switching where you switch to an 80 MHz link and expect
it to be active immediately, but the mindef is still configured
to 20 MHz while assigning. Also, it's strange that the chandef
passed to the assign method's argument is wider than the one in
the context.
Fix this by calculating the mindef with the new link considered
before calling the driver.
In particular, this fixes an iwlwifi problem during link switch
where the firmware would assert because the (link) station that
was added for the AP is configured to transmit at a bandwidth
that's wider than the channel context that it's configured on.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230504134511.828474-5-gregory.greenman@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When a chanctx is reserved for a new vif and we recalculate
the minimal definition for it, we need to consider the new
interface it's being reserved for before we assign it, so it
can be used directly with the correct min channel width.
Fix the code to - optionally - consider that, and use that
option just before doing the reassignment.
Also, when considering channel context reservations, we
should only consider the one link we're currently working with.
Change the boolean argument to a link pointer to do that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230504134511.828474-4-gregory.greenman@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
There's no need to call ieee80211_recalc_chanctx_min_def()
since it cannot and won't call the driver anyway; just use
_ieee80211_recalc_chanctx_min_def() instead.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230504134511.828474-3-gregory.greenman@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Handle the Puncturing info received from the AP in the
EHT Operation element in beacons.
If the info is invalid:
- during association: disable EHT connection for the AP
- after association: disconnect
This commit includes many (internal) bugfixes and spec
updates various people.
Co-developed-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://lore.kernel.org/r/20230127123930.4fbc74582331.I3547481d49f958389f59dfeba3fcc75e72b0aa6e@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In order to let the driver select active links and properly
make multi-link connections, as a first step isolate the
driver from inactive links, and set the active links to be
only the association link for client-side interfaces. For
AP side nothing changes since APs always have to have all
their links active.
To simplify things, update the for_each_sta_active_link()
API to include the appropriate vif pointer.
This also implies not allocating a chanctx for an inactive
link, which requires a few more changes.
Since we now no longer try to program multiple links to the
driver, remove the check in the MLME code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since mac80211 already has a protected pointer to link_conf,
pass it to the driver to avoid additional RCU locking.
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We check here that we don't enable TX (netif_carrier_ok())
before we actually start using some channel context, but to
our knowledge this check has never triggered, and with MLO
it's just wrong since links can be added and removed much
more dynamically than before.
Simply remove the checks, there's no really good way to do
anything that would replace them.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When we remove a link that doesn't have a channel context,
we don't really need the local->mtx locking. Tighten the
check here.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Do the first adjustments in the client-side code to pass
the link pointer (instead of sdata) to most places etc.
This is just preparation, so the real MLO patches become
smaller.
Note that this isn't complete, notably there are still
quite a few references to sta->deflink and sta->sta.deflink.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Since links can be added and removed dynamically, we need to
somehow protect the sdata->link[] and vif->link_conf[] array
pointers from disappearing when accessing them without locks.
RCU-ify the pointers to achieve this, which requires quite a
bit of rework.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We need to be able to access these in a race-free way under
traffic while adding/removing them, so RCU-ify the pointers.
This requires passing a link_sta to a lot of functions so
we don't have to do the RCU handling everywhere.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Make the channel context code MLO aware, along with some
functions that it uses, so that the chan.c file is now
MLD-clean and no longer uses deflink/bss_conf/etc.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Split the bss_info_changed method to vif_cfg_changed and
link_info_changed, with the latter getting a link ID.
Also change the 'changed' parameter to u64 already, we
know we need that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Start reorganizing interface related data structures toward
MLD. The most complex part here is for the keys, since we
have to split the various kinds of GTKs off to the link but
still need to use (for WEP) the other keys as a fallback
even for multicast frames.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We'll use bss_conf for per-link configuration later, so
move out all the non-link-specific data out into a new
struct ieee80211_vif_cfg used in the vif.
Some adjustments were done with the following spatch:
@@
expression sdata;
struct ieee80211_vif *vifp;
identifier var = { assoc, ibss_joined, aid, arp_addr_list, arp_addr_cnt, ssid, ssid_len, s1g, ibss_creator };
@@
(
-sdata->vif.bss_conf.var
+sdata->vif.cfg.var
|
-vifp->bss_conf.var
+vifp->cfg.var
)
@bss_conf@
struct ieee80211_bss_conf *bss_conf;
identifier var = { assoc, ibss_joined, aid, arp_addr_list, arp_addr_cnt, ssid, ssid_len, s1g, ibss_creator };
@@
-bss_conf->var
+vif_cfg->var
(though more manual fixups were needed, e.g. replacing
"vif_cfg->" by "vif->cfg." in many files.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
To add MLD, reuse the bss_conf structure later for per-link
information, so move some things into it that are per link.
Most transformations were done with the following spatch:
@@
expression sdata;
identifier var = { chanctx_conf, mu_mimo_owner, csa_active, color_change_active, color_change_color };
@@
-sdata->vif.var
+sdata->vif.bss_conf.var
@@
struct ieee80211_vif *vif;
identifier var = { chanctx_conf, mu_mimo_owner, csa_active, color_change_active, color_change_color };
@@
-vif->var
+vif->bss_conf.var
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In ieee80211_vif_use_reserved_context(), when we have an
old context and the new context's replace_state is set to
IEEE80211_CHANCTX_REPLACE_NONE, we free the old context
in ieee80211_vif_use_reserved_reassign(). Therefore, we
cannot check the old_ctx anymore, so we should set it to
NULL after this point.
However, since the new_ctx replace state is clearly not
IEEE80211_CHANCTX_REPLACES_OTHER, we're not going to do
anything else in this function and can just return to
avoid accessing the freed old_ctx.
Cc: stable@vger.kernel.org
Fixes: 5bcae31d9c ("mac80211: implement multi-vif in-place reservations")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20220601091926.df419d91b165.I17a9b3894ff0b8323ce2afdb153b101124c821e5@changeid
