<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/net/mac80211/tx.c, branch v6.4</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>wifi: mac80211: Use active_links instead of valid_links in Tx</title>
<updated>2023-06-09T11:31:08+00:00</updated>
<author>
<name>Ilan Peer</name>
<email>ilan.peer@intel.com</email>
</author>
<published>2023-06-08T13:36:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7b3b9ac899b54f53f7c9fc07e1c562f56b2187fa'/>
<id>7b3b9ac899b54f53f7c9fc07e1c562f56b2187fa</id>
<content type='text'>
Fix few places on the Tx path where the valid_links were used instead
of active links.

Signed-off-by: Ilan Peer &lt;ilan.peer@intel.com&gt;
Signed-off-by: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Link: https://lore.kernel.org/r/20230608163202.e24832691fc8.I9ac10dc246d7798a8d26b1a94933df5668df63fc@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix few places on the Tx path where the valid_links were used instead
of active links.

Signed-off-by: Ilan Peer &lt;ilan.peer@intel.com&gt;
Signed-off-by: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Link: https://lore.kernel.org/r/20230608163202.e24832691fc8.I9ac10dc246d7798a8d26b1a94933df5668df63fc@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: fix switch count in EMA beacons</title>
<updated>2023-06-06T08:20:45+00:00</updated>
<author>
<name>Aditya Kumar Singh</name>
<email>quic_adisi@quicinc.com</email>
</author>
<published>2023-05-31T06:20:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1afa18e9e72396d1e1aedd6dbb34681f2413316b'/>
<id>1afa18e9e72396d1e1aedd6dbb34681f2413316b</id>
<content type='text'>
Currently, whenever an EMA beacon is formed, due to is_template
argument being false from the caller, the switch count is always
decremented once which is wrong.

Also if switch count is equal to profile periodicity, this makes
the switch count to reach till zero which triggers a WARN_ON_ONCE.

[  261.593915] CPU: 1 PID: 800 Comm: kworker/u8:3 Not tainted 5.4.213 #0
[  261.616143] Hardware name: Qualcomm Technologies, Inc. IPQ9574
[  261.622666] Workqueue: phy0 ath12k_get_link_bss_conf [ath12k]
[  261.629771] pstate: 60400005 (nZCv daif +PAN -UAO)
[  261.635595] pc : ieee80211_next_txq+0x1ac/0x1b8 [mac80211]
[  261.640282] lr : ieee80211_beacon_update_cntdwn+0x64/0xb4 [mac80211]
[...]
[  261.729683] Call trace:
[  261.734986]  ieee80211_next_txq+0x1ac/0x1b8 [mac80211]
[  261.737156]  ieee80211_beacon_cntdwn_is_complete+0xa28/0x1194 [mac80211]
[  261.742365]  ieee80211_beacon_cntdwn_is_complete+0xef4/0x1194 [mac80211]
[  261.749224]  ieee80211_beacon_get_template_ema_list+0x38/0x5c [mac80211]
[  261.755908]  ath12k_get_link_bss_conf+0xf8/0x33b4 [ath12k]
[  261.762590]  ath12k_get_link_bss_conf+0x390/0x33b4 [ath12k]
[  261.767881]  process_one_work+0x194/0x270
[  261.773346]  worker_thread+0x200/0x314
[  261.777514]  kthread+0x140/0x150
[  261.781158]  ret_from_fork+0x10/0x18

Fix this issue by making the is_template argument as true when fetching
the EMA beacons.

Fixes: bd54f3c29077 ("wifi: mac80211: generate EMA beacons in AP mode")
Signed-off-by: Aditya Kumar Singh &lt;quic_adisi@quicinc.com&gt;
Link: https://lore.kernel.org/r/20230531062012.4537-1-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently, whenever an EMA beacon is formed, due to is_template
argument being false from the caller, the switch count is always
decremented once which is wrong.

Also if switch count is equal to profile periodicity, this makes
the switch count to reach till zero which triggers a WARN_ON_ONCE.

[  261.593915] CPU: 1 PID: 800 Comm: kworker/u8:3 Not tainted 5.4.213 #0
[  261.616143] Hardware name: Qualcomm Technologies, Inc. IPQ9574
[  261.622666] Workqueue: phy0 ath12k_get_link_bss_conf [ath12k]
[  261.629771] pstate: 60400005 (nZCv daif +PAN -UAO)
[  261.635595] pc : ieee80211_next_txq+0x1ac/0x1b8 [mac80211]
[  261.640282] lr : ieee80211_beacon_update_cntdwn+0x64/0xb4 [mac80211]
[...]
[  261.729683] Call trace:
[  261.734986]  ieee80211_next_txq+0x1ac/0x1b8 [mac80211]
[  261.737156]  ieee80211_beacon_cntdwn_is_complete+0xa28/0x1194 [mac80211]
[  261.742365]  ieee80211_beacon_cntdwn_is_complete+0xef4/0x1194 [mac80211]
[  261.749224]  ieee80211_beacon_get_template_ema_list+0x38/0x5c [mac80211]
[  261.755908]  ath12k_get_link_bss_conf+0xf8/0x33b4 [ath12k]
[  261.762590]  ath12k_get_link_bss_conf+0x390/0x33b4 [ath12k]
[  261.767881]  process_one_work+0x194/0x270
[  261.773346]  worker_thread+0x200/0x314
[  261.777514]  kthread+0x140/0x150
[  261.781158]  ret_from_fork+0x10/0x18

Fix this issue by making the is_template argument as true when fetching
the EMA beacons.

Fixes: bd54f3c29077 ("wifi: mac80211: generate EMA beacons in AP mode")
Signed-off-by: Aditya Kumar Singh &lt;quic_adisi@quicinc.com&gt;
Link: https://lore.kernel.org/r/20230531062012.4537-1-quic_adisi@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: fortify the spinlock against deadlock by interrupt</title>
<updated>2023-05-16T17:11:38+00:00</updated>
<author>
<name>Mirsad Goran Todorovac</name>
<email>mirsad.todorovac@alu.unizg.hr</email>
</author>
<published>2023-04-25T16:40:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ef6e1997da63ad0ac3fe33153fec9524c9ae56c9'/>
<id>ef6e1997da63ad0ac3fe33153fec9524c9ae56c9</id>
<content type='text'>
In the function ieee80211_tx_dequeue() there is a particular locking
sequence:

begin:
	spin_lock(&amp;local-&gt;queue_stop_reason_lock);
	q_stopped = local-&gt;queue_stop_reasons[q];
	spin_unlock(&amp;local-&gt;queue_stop_reason_lock);

However small the chance (increased by ftracetest), an asynchronous
interrupt can occur in between of spin_lock() and spin_unlock(),
and the interrupt routine will attempt to lock the same
&amp;local-&gt;queue_stop_reason_lock again.

This will cause a costly reset of the CPU and the wifi device or an
altogether hang in the single CPU and single core scenario.

The only remaining spin_lock(&amp;local-&gt;queue_stop_reason_lock) that
did not disable interrupts was patched, which should prevent any
deadlocks on the same CPU/core and the same wifi device.

This is the probable trace of the deadlock:

kernel: ================================
kernel: WARNING: inconsistent lock state
kernel: 6.3.0-rc6-mt-20230401-00001-gf86822a1170f #4 Tainted: G        W
kernel: --------------------------------
kernel: inconsistent {IN-SOFTIRQ-W} -&gt; {SOFTIRQ-ON-W} usage.
kernel: kworker/5:0/25656 [HC0[0]:SC0[0]:HE1:SE1] takes:
kernel: ffff9d6190779478 (&amp;local-&gt;queue_stop_reason_lock){+.?.}-{2:2}, at: return_to_handler+0x0/0x40
kernel: {IN-SOFTIRQ-W} state was registered at:
kernel:   lock_acquire+0xc7/0x2d0
kernel:   _raw_spin_lock+0x36/0x50
kernel:   ieee80211_tx_dequeue+0xb4/0x1330 [mac80211]
kernel:   iwl_mvm_mac_itxq_xmit+0xae/0x210 [iwlmvm]
kernel:   iwl_mvm_mac_wake_tx_queue+0x2d/0xd0 [iwlmvm]
kernel:   ieee80211_queue_skb+0x450/0x730 [mac80211]
kernel:   __ieee80211_xmit_fast.constprop.66+0x834/0xa50 [mac80211]
kernel:   __ieee80211_subif_start_xmit+0x217/0x530 [mac80211]
kernel:   ieee80211_subif_start_xmit+0x60/0x580 [mac80211]
kernel:   dev_hard_start_xmit+0xb5/0x260
kernel:   __dev_queue_xmit+0xdbe/0x1200
kernel:   neigh_resolve_output+0x166/0x260
kernel:   ip_finish_output2+0x216/0xb80
kernel:   __ip_finish_output+0x2a4/0x4d0
kernel:   ip_finish_output+0x2d/0xd0
kernel:   ip_output+0x82/0x2b0
kernel:   ip_local_out+0xec/0x110
kernel:   igmpv3_sendpack+0x5c/0x90
kernel:   igmp_ifc_timer_expire+0x26e/0x4e0
kernel:   call_timer_fn+0xa5/0x230
kernel:   run_timer_softirq+0x27f/0x550
kernel:   __do_softirq+0xb4/0x3a4
kernel:   irq_exit_rcu+0x9b/0xc0
kernel:   sysvec_apic_timer_interrupt+0x80/0xa0
kernel:   asm_sysvec_apic_timer_interrupt+0x1f/0x30
kernel:   _raw_spin_unlock_irqrestore+0x3f/0x70
kernel:   free_to_partial_list+0x3d6/0x590
kernel:   __slab_free+0x1b7/0x310
kernel:   kmem_cache_free+0x52d/0x550
kernel:   putname+0x5d/0x70
kernel:   do_sys_openat2+0x1d7/0x310
kernel:   do_sys_open+0x51/0x80
kernel:   __x64_sys_openat+0x24/0x30
kernel:   do_syscall_64+0x5c/0x90
kernel:   entry_SYSCALL_64_after_hwframe+0x72/0xdc
kernel: irq event stamp: 5120729
kernel: hardirqs last  enabled at (5120729): [&lt;ffffffff9d149936&gt;] trace_graph_return+0xd6/0x120
kernel: hardirqs last disabled at (5120728): [&lt;ffffffff9d149950&gt;] trace_graph_return+0xf0/0x120
kernel: softirqs last  enabled at (5069900): [&lt;ffffffff9cf65b60&gt;] return_to_handler+0x0/0x40
kernel: softirqs last disabled at (5067555): [&lt;ffffffff9cf65b60&gt;] return_to_handler+0x0/0x40
kernel:
        other info that might help us debug this:
kernel:  Possible unsafe locking scenario:
kernel:        CPU0
kernel:        ----
kernel:   lock(&amp;local-&gt;queue_stop_reason_lock);
kernel:   &lt;Interrupt&gt;
kernel:     lock(&amp;local-&gt;queue_stop_reason_lock);
kernel:
         *** DEADLOCK ***
kernel: 8 locks held by kworker/5:0/25656:
kernel:  #0: ffff9d618009d138 ((wq_completion)events_freezable){+.+.}-{0:0}, at: process_one_work+0x1ca/0x530
kernel:  #1: ffffb1ef4637fe68 ((work_completion)(&amp;local-&gt;restart_work)){+.+.}-{0:0}, at: process_one_work+0x1ce/0x530
kernel:  #2: ffffffff9f166548 (rtnl_mutex){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #3: ffff9d6190778728 (&amp;rdev-&gt;wiphy.mtx){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #4: ffff9d619077b480 (&amp;mvm-&gt;mutex){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #5: ffff9d61907bacd8 (&amp;trans_pcie-&gt;mutex){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #6: ffffffff9ef9cda0 (rcu_read_lock){....}-{1:2}, at: iwl_mvm_queue_state_change+0x59/0x3a0 [iwlmvm]
kernel:  #7: ffffffff9ef9cda0 (rcu_read_lock){....}-{1:2}, at: iwl_mvm_mac_itxq_xmit+0x42/0x210 [iwlmvm]
kernel:
        stack backtrace:
kernel: CPU: 5 PID: 25656 Comm: kworker/5:0 Tainted: G        W          6.3.0-rc6-mt-20230401-00001-gf86822a1170f #4
kernel: Hardware name: LENOVO 82H8/LNVNB161216, BIOS GGCN51WW 11/16/2022
kernel: Workqueue: events_freezable ieee80211_restart_work [mac80211]
kernel: Call Trace:
kernel:  &lt;TASK&gt;
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  dump_stack_lvl+0x5f/0xa0
kernel:  dump_stack+0x14/0x20
kernel:  print_usage_bug.part.46+0x208/0x2a0
kernel:  mark_lock.part.47+0x605/0x630
kernel:  ? sched_clock+0xd/0x20
kernel:  ? trace_clock_local+0x14/0x30
kernel:  ? __rb_reserve_next+0x5f/0x490
kernel:  ? _raw_spin_lock+0x1b/0x50
kernel:  __lock_acquire+0x464/0x1990
kernel:  ? mark_held_locks+0x4e/0x80
kernel:  lock_acquire+0xc7/0x2d0
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ? ftrace_return_to_handler+0x8b/0x100
kernel:  ? preempt_count_add+0x4/0x70
kernel:  _raw_spin_lock+0x36/0x50
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ieee80211_tx_dequeue+0xb4/0x1330 [mac80211]
kernel:  ? prepare_ftrace_return+0xc5/0x190
kernel:  ? ftrace_graph_func+0x16/0x20
kernel:  ? 0xffffffffc02ab0b1
kernel:  ? lock_acquire+0xc7/0x2d0
kernel:  ? iwl_mvm_mac_itxq_xmit+0x42/0x210 [iwlmvm]
kernel:  ? ieee80211_tx_dequeue+0x9/0x1330 [mac80211]
kernel:  ? __rcu_read_lock+0x4/0x40
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_mac_itxq_xmit+0xae/0x210 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_queue_state_change+0x311/0x3a0 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_wake_sw_queue+0x17/0x20 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_txq_gen2_unmap+0x1c9/0x1f0 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_txq_gen2_free+0x55/0x130 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_txq_gen2_tx_free+0x63/0x80 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  _iwl_trans_pcie_gen2_stop_device+0x3f3/0x5b0 [iwlwifi]
kernel:  ? _iwl_trans_pcie_gen2_stop_device+0x9/0x5b0 [iwlwifi]
kernel:  ? mutex_lock_nested+0x4/0x30
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_trans_pcie_gen2_stop_device+0x5f/0x90 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_stop_device+0x78/0xd0 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  __iwl_mvm_mac_start+0x114/0x210 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_mac_start+0x76/0x150 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  drv_start+0x79/0x180 [mac80211]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ieee80211_reconfig+0x1523/0x1ce0 [mac80211]
kernel:  ? synchronize_net+0x4/0x50
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ieee80211_restart_work+0x108/0x170 [mac80211]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  process_one_work+0x250/0x530
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  worker_thread+0x48/0x3a0
kernel:  ? __pfx_worker_thread+0x10/0x10
kernel:  kthread+0x10f/0x140
kernel:  ? __pfx_kthread+0x10/0x10
kernel:  ret_from_fork+0x29/0x50
kernel:  &lt;/TASK&gt;

Fixes: 4444bc2116ae ("wifi: mac80211: Proper mark iTXQs for resumption")
Link: https://lore.kernel.org/all/1f58a0d1-d2b9-d851-73c3-93fcc607501c@alu.unizg.hr/
Reported-by: Mirsad Goran Todorovac &lt;mirsad.todorovac@alu.unizg.hr&gt;
Cc: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Cc: Johannes Berg &lt;johannes.berg@intel.com&gt;
Link: https://lore.kernel.org/all/cdc80531-f25f-6f9d-b15f-25e16130b53a@alu.unizg.hr/
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: Paolo Abeni &lt;pabeni@redhat.com&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Alexander Wetzel &lt;alexander@wetzel-home.de&gt;
Signed-off-by: Mirsad Goran Todorovac &lt;mirsad.todorovac@alu.unizg.hr&gt;
Reviewed-by: Leon Romanovsky &lt;leonro@nvidia.com&gt;
Reviewed-by: tag, or it goes automatically?
Link: https://lore.kernel.org/r/20230425164005.25272-1-mirsad.todorovac@alu.unizg.hr
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In the function ieee80211_tx_dequeue() there is a particular locking
sequence:

begin:
	spin_lock(&amp;local-&gt;queue_stop_reason_lock);
	q_stopped = local-&gt;queue_stop_reasons[q];
	spin_unlock(&amp;local-&gt;queue_stop_reason_lock);

However small the chance (increased by ftracetest), an asynchronous
interrupt can occur in between of spin_lock() and spin_unlock(),
and the interrupt routine will attempt to lock the same
&amp;local-&gt;queue_stop_reason_lock again.

This will cause a costly reset of the CPU and the wifi device or an
altogether hang in the single CPU and single core scenario.

The only remaining spin_lock(&amp;local-&gt;queue_stop_reason_lock) that
did not disable interrupts was patched, which should prevent any
deadlocks on the same CPU/core and the same wifi device.

This is the probable trace of the deadlock:

kernel: ================================
kernel: WARNING: inconsistent lock state
kernel: 6.3.0-rc6-mt-20230401-00001-gf86822a1170f #4 Tainted: G        W
kernel: --------------------------------
kernel: inconsistent {IN-SOFTIRQ-W} -&gt; {SOFTIRQ-ON-W} usage.
kernel: kworker/5:0/25656 [HC0[0]:SC0[0]:HE1:SE1] takes:
kernel: ffff9d6190779478 (&amp;local-&gt;queue_stop_reason_lock){+.?.}-{2:2}, at: return_to_handler+0x0/0x40
kernel: {IN-SOFTIRQ-W} state was registered at:
kernel:   lock_acquire+0xc7/0x2d0
kernel:   _raw_spin_lock+0x36/0x50
kernel:   ieee80211_tx_dequeue+0xb4/0x1330 [mac80211]
kernel:   iwl_mvm_mac_itxq_xmit+0xae/0x210 [iwlmvm]
kernel:   iwl_mvm_mac_wake_tx_queue+0x2d/0xd0 [iwlmvm]
kernel:   ieee80211_queue_skb+0x450/0x730 [mac80211]
kernel:   __ieee80211_xmit_fast.constprop.66+0x834/0xa50 [mac80211]
kernel:   __ieee80211_subif_start_xmit+0x217/0x530 [mac80211]
kernel:   ieee80211_subif_start_xmit+0x60/0x580 [mac80211]
kernel:   dev_hard_start_xmit+0xb5/0x260
kernel:   __dev_queue_xmit+0xdbe/0x1200
kernel:   neigh_resolve_output+0x166/0x260
kernel:   ip_finish_output2+0x216/0xb80
kernel:   __ip_finish_output+0x2a4/0x4d0
kernel:   ip_finish_output+0x2d/0xd0
kernel:   ip_output+0x82/0x2b0
kernel:   ip_local_out+0xec/0x110
kernel:   igmpv3_sendpack+0x5c/0x90
kernel:   igmp_ifc_timer_expire+0x26e/0x4e0
kernel:   call_timer_fn+0xa5/0x230
kernel:   run_timer_softirq+0x27f/0x550
kernel:   __do_softirq+0xb4/0x3a4
kernel:   irq_exit_rcu+0x9b/0xc0
kernel:   sysvec_apic_timer_interrupt+0x80/0xa0
kernel:   asm_sysvec_apic_timer_interrupt+0x1f/0x30
kernel:   _raw_spin_unlock_irqrestore+0x3f/0x70
kernel:   free_to_partial_list+0x3d6/0x590
kernel:   __slab_free+0x1b7/0x310
kernel:   kmem_cache_free+0x52d/0x550
kernel:   putname+0x5d/0x70
kernel:   do_sys_openat2+0x1d7/0x310
kernel:   do_sys_open+0x51/0x80
kernel:   __x64_sys_openat+0x24/0x30
kernel:   do_syscall_64+0x5c/0x90
kernel:   entry_SYSCALL_64_after_hwframe+0x72/0xdc
kernel: irq event stamp: 5120729
kernel: hardirqs last  enabled at (5120729): [&lt;ffffffff9d149936&gt;] trace_graph_return+0xd6/0x120
kernel: hardirqs last disabled at (5120728): [&lt;ffffffff9d149950&gt;] trace_graph_return+0xf0/0x120
kernel: softirqs last  enabled at (5069900): [&lt;ffffffff9cf65b60&gt;] return_to_handler+0x0/0x40
kernel: softirqs last disabled at (5067555): [&lt;ffffffff9cf65b60&gt;] return_to_handler+0x0/0x40
kernel:
        other info that might help us debug this:
kernel:  Possible unsafe locking scenario:
kernel:        CPU0
kernel:        ----
kernel:   lock(&amp;local-&gt;queue_stop_reason_lock);
kernel:   &lt;Interrupt&gt;
kernel:     lock(&amp;local-&gt;queue_stop_reason_lock);
kernel:
         *** DEADLOCK ***
kernel: 8 locks held by kworker/5:0/25656:
kernel:  #0: ffff9d618009d138 ((wq_completion)events_freezable){+.+.}-{0:0}, at: process_one_work+0x1ca/0x530
kernel:  #1: ffffb1ef4637fe68 ((work_completion)(&amp;local-&gt;restart_work)){+.+.}-{0:0}, at: process_one_work+0x1ce/0x530
kernel:  #2: ffffffff9f166548 (rtnl_mutex){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #3: ffff9d6190778728 (&amp;rdev-&gt;wiphy.mtx){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #4: ffff9d619077b480 (&amp;mvm-&gt;mutex){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #5: ffff9d61907bacd8 (&amp;trans_pcie-&gt;mutex){+.+.}-{3:3}, at: return_to_handler+0x0/0x40
kernel:  #6: ffffffff9ef9cda0 (rcu_read_lock){....}-{1:2}, at: iwl_mvm_queue_state_change+0x59/0x3a0 [iwlmvm]
kernel:  #7: ffffffff9ef9cda0 (rcu_read_lock){....}-{1:2}, at: iwl_mvm_mac_itxq_xmit+0x42/0x210 [iwlmvm]
kernel:
        stack backtrace:
kernel: CPU: 5 PID: 25656 Comm: kworker/5:0 Tainted: G        W          6.3.0-rc6-mt-20230401-00001-gf86822a1170f #4
kernel: Hardware name: LENOVO 82H8/LNVNB161216, BIOS GGCN51WW 11/16/2022
kernel: Workqueue: events_freezable ieee80211_restart_work [mac80211]
kernel: Call Trace:
kernel:  &lt;TASK&gt;
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  dump_stack_lvl+0x5f/0xa0
kernel:  dump_stack+0x14/0x20
kernel:  print_usage_bug.part.46+0x208/0x2a0
kernel:  mark_lock.part.47+0x605/0x630
kernel:  ? sched_clock+0xd/0x20
kernel:  ? trace_clock_local+0x14/0x30
kernel:  ? __rb_reserve_next+0x5f/0x490
kernel:  ? _raw_spin_lock+0x1b/0x50
kernel:  __lock_acquire+0x464/0x1990
kernel:  ? mark_held_locks+0x4e/0x80
kernel:  lock_acquire+0xc7/0x2d0
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ? ftrace_return_to_handler+0x8b/0x100
kernel:  ? preempt_count_add+0x4/0x70
kernel:  _raw_spin_lock+0x36/0x50
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ieee80211_tx_dequeue+0xb4/0x1330 [mac80211]
kernel:  ? prepare_ftrace_return+0xc5/0x190
kernel:  ? ftrace_graph_func+0x16/0x20
kernel:  ? 0xffffffffc02ab0b1
kernel:  ? lock_acquire+0xc7/0x2d0
kernel:  ? iwl_mvm_mac_itxq_xmit+0x42/0x210 [iwlmvm]
kernel:  ? ieee80211_tx_dequeue+0x9/0x1330 [mac80211]
kernel:  ? __rcu_read_lock+0x4/0x40
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_mac_itxq_xmit+0xae/0x210 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_queue_state_change+0x311/0x3a0 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_wake_sw_queue+0x17/0x20 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_txq_gen2_unmap+0x1c9/0x1f0 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_txq_gen2_free+0x55/0x130 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_txq_gen2_tx_free+0x63/0x80 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  _iwl_trans_pcie_gen2_stop_device+0x3f3/0x5b0 [iwlwifi]
kernel:  ? _iwl_trans_pcie_gen2_stop_device+0x9/0x5b0 [iwlwifi]
kernel:  ? mutex_lock_nested+0x4/0x30
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_trans_pcie_gen2_stop_device+0x5f/0x90 [iwlwifi]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_stop_device+0x78/0xd0 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  __iwl_mvm_mac_start+0x114/0x210 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  iwl_mvm_mac_start+0x76/0x150 [iwlmvm]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  drv_start+0x79/0x180 [mac80211]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ieee80211_reconfig+0x1523/0x1ce0 [mac80211]
kernel:  ? synchronize_net+0x4/0x50
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  ieee80211_restart_work+0x108/0x170 [mac80211]
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  process_one_work+0x250/0x530
kernel:  ? ftrace_regs_caller_end+0x66/0x66
kernel:  worker_thread+0x48/0x3a0
kernel:  ? __pfx_worker_thread+0x10/0x10
kernel:  kthread+0x10f/0x140
kernel:  ? __pfx_kthread+0x10/0x10
kernel:  ret_from_fork+0x29/0x50
kernel:  &lt;/TASK&gt;

Fixes: 4444bc2116ae ("wifi: mac80211: Proper mark iTXQs for resumption")
Link: https://lore.kernel.org/all/1f58a0d1-d2b9-d851-73c3-93fcc607501c@alu.unizg.hr/
Reported-by: Mirsad Goran Todorovac &lt;mirsad.todorovac@alu.unizg.hr&gt;
Cc: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Cc: Johannes Berg &lt;johannes.berg@intel.com&gt;
Link: https://lore.kernel.org/all/cdc80531-f25f-6f9d-b15f-25e16130b53a@alu.unizg.hr/
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Jakub Kicinski &lt;kuba@kernel.org&gt;
Cc: Paolo Abeni &lt;pabeni@redhat.com&gt;
Cc: Leon Romanovsky &lt;leon@kernel.org&gt;
Cc: Alexander Wetzel &lt;alexander@wetzel-home.de&gt;
Signed-off-by: Mirsad Goran Todorovac &lt;mirsad.todorovac@alu.unizg.hr&gt;
Reviewed-by: Leon Romanovsky &lt;leonro@nvidia.com&gt;
Reviewed-by: tag, or it goes automatically?
Link: https://lore.kernel.org/r/20230425164005.25272-1-mirsad.todorovac@alu.unizg.hr
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: ieee80211: correctly mark FTM frames non-bufferable</title>
<updated>2023-04-13T14:32:02+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2023-03-31T14:59:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2c9abe653bc5134eeab411c46dde008d8a1c37b0'/>
<id>2c9abe653bc5134eeab411c46dde008d8a1c37b0</id>
<content type='text'>
The checks of whether or not a frame is bufferable were not
taking into account that some action frames aren't, such as
FTM. Check this, which requires some changes to the function
ieee80211_is_bufferable_mmpdu() since we need the whole skb
for the checks now.

Reviewed-by: Ilan Peer &lt;ilan.peer@intel.com&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The checks of whether or not a frame is bufferable were not
taking into account that some action frames aren't, such as
FTM. Check this, which requires some changes to the function
ieee80211_is_bufferable_mmpdu() since we need the whole skb
for the checks now.

Reviewed-by: Ilan Peer &lt;ilan.peer@intel.com&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mac80211: support RNR for EMA AP</title>
<updated>2023-03-24T10:12:48+00:00</updated>
<author>
<name>Aloka Dixit</name>
<email>quic_alokad@quicinc.com</email>
</author>
<published>2023-03-23T11:38:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=68b9bea267bfc1259e195dcac1bf69db0c0c28da'/>
<id>68b9bea267bfc1259e195dcac1bf69db0c0c28da</id>
<content type='text'>
Generate EMA beacons, each including MBSSID and RNR elements at a given
index. If number of stored RNR elements is more than the number of
MBSSID elements then add those in every EMA beacon.

Signed-off-by: Aloka Dixit &lt;quic_alokad@quicinc.com&gt;
Link: https://lore.kernel.org/r/20230323113801.6903-3-quic_alokad@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Generate EMA beacons, each including MBSSID and RNR elements at a given
index. If number of stored RNR elements is more than the number of
MBSSID elements then add those in every EMA beacon.

Signed-off-by: Aloka Dixit &lt;quic_alokad@quicinc.com&gt;
Link: https://lore.kernel.org/r/20230323113801.6903-3-quic_alokad@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: generate EMA beacons in AP mode</title>
<updated>2023-03-22T12:54:57+00:00</updated>
<author>
<name>Aloka Dixit</name>
<email>quic_alokad@quicinc.com</email>
</author>
<published>2022-12-06T00:50:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=bd54f3c29077f23dad92ef82a78061b40be30c65'/>
<id>bd54f3c29077f23dad92ef82a78061b40be30c65</id>
<content type='text'>
Add APIs to generate an array of beacons for an EMA AP (enhanced
multiple BSSID advertisements), each including a single MBSSID element.
EMA profile periodicity equals the count of elements.

- ieee80211_beacon_get_template_ema_list() - Generate and return all
EMA beacon templates. Drivers must call ieee80211_beacon_free_ema_list()
to free the memory. No change in the prototype for the existing API,
ieee80211_beacon_get_template(), which should be used for non-EMA AP.

- ieee80211_beacon_get_template_ema_index() - Generate a beacon which
includes the multiple BSSID element at the given index. Drivers can use
this function in a loop until NULL is returned which indicates end of
available MBSSID elements.

- ieee80211_beacon_free_ema_list() - free the memory allocated for the
list of EMA beacon templates.

Modify existing functions ieee80211_beacon_get_ap(),
ieee80211_get_mbssid_beacon_len() and ieee80211_beacon_add_mbssid()
to accept a new parameter for EMA index.

Signed-off-by: Aloka Dixit &lt;quic_alokad@quicinc.com&gt;
Co-developed-by: John Crispin &lt;john@phrozen.org&gt;
Signed-off-by: John Crispin &lt;john@phrozen.org&gt;
Link: https://lore.kernel.org/r/20221206005040.3177-2-quic_alokad@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add APIs to generate an array of beacons for an EMA AP (enhanced
multiple BSSID advertisements), each including a single MBSSID element.
EMA profile periodicity equals the count of elements.

- ieee80211_beacon_get_template_ema_list() - Generate and return all
EMA beacon templates. Drivers must call ieee80211_beacon_free_ema_list()
to free the memory. No change in the prototype for the existing API,
ieee80211_beacon_get_template(), which should be used for non-EMA AP.

- ieee80211_beacon_get_template_ema_index() - Generate a beacon which
includes the multiple BSSID element at the given index. Drivers can use
this function in a loop until NULL is returned which indicates end of
available MBSSID elements.

- ieee80211_beacon_free_ema_list() - free the memory allocated for the
list of EMA beacon templates.

Modify existing functions ieee80211_beacon_get_ap(),
ieee80211_get_mbssid_beacon_len() and ieee80211_beacon_add_mbssid()
to accept a new parameter for EMA index.

Signed-off-by: Aloka Dixit &lt;quic_alokad@quicinc.com&gt;
Co-developed-by: John Crispin &lt;john@phrozen.org&gt;
Signed-off-by: John Crispin &lt;john@phrozen.org&gt;
Link: https://lore.kernel.org/r/20221206005040.3177-2-quic_alokad@quicinc.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: use mesh header cache to speed up mesh forwarding</title>
<updated>2023-03-22T12:31:19+00:00</updated>
<author>
<name>Felix Fietkau</name>
<email>nbd@nbd.name</email>
</author>
<published>2023-03-14T09:59:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8b0f5cb6bc7cbbee4d78b3221683dcb4d1ed23d0'/>
<id>8b0f5cb6bc7cbbee4d78b3221683dcb4d1ed23d0</id>
<content type='text'>
Significantly reduces mesh forwarding path CPU usage and enables the
direct use of iTXQ.

Signed-off-by: Felix Fietkau &lt;nbd@nbd.name&gt;
Signed-off-by: Ryder Lee &lt;ryder.lee@mediatek.com&gt;
Link: https://lore.kernel.org/r/20230314095956.62085-5-nbd@nbd.name
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Significantly reduces mesh forwarding path CPU usage and enables the
direct use of iTXQ.

Signed-off-by: Felix Fietkau &lt;nbd@nbd.name&gt;
Signed-off-by: Ryder Lee &lt;ryder.lee@mediatek.com&gt;
Link: https://lore.kernel.org/r/20230314095956.62085-5-nbd@nbd.name
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: mesh fast xmit support</title>
<updated>2023-03-22T12:31:18+00:00</updated>
<author>
<name>Felix Fietkau</name>
<email>nbd@nbd.name</email>
</author>
<published>2023-03-14T09:59:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d5edb9ae8d568745f893c5c5fa3837d85311b131'/>
<id>d5edb9ae8d568745f893c5c5fa3837d85311b131</id>
<content type='text'>
Previously, fast xmit only worked on interface types where initially a
sta lookup is performed, and a cached header can be attached to the sta,
requiring only some fields to be updated at runtime.

This technique is not directly applicable for a mesh device type due
to the dynamic nature of the topology and protocol. There are more
addresses that need to be filled, and there is an extra header with a
dynamic length based on the addressing mode.

Change the code to cache entries contain a copy of the mesh subframe header +
bridge tunnel header, as well as an embedded struct ieee80211_fast_tx, which
contains the information for building the 802.11 header.

Add a mesh specific early fast xmit call, which looks up a cached entry and
adds only the mesh subframe header, before passing it over to the generic
fast xmit code.

To ensure the changes in network are reflected in these cached headers,
flush affected cached entries on path changes, as well as other conditions
that currently trigger a fast xmit check in other modes (key changes etc.)

This code is loosely based on a previous implementation by:
Sriram R &lt;quic_srirrama@quicinc.com&gt;

Cc: Sriram R &lt;quic_srirrama@quicinc.com&gt;
Signed-off-by: Ryder Lee &lt;ryder.lee@mediatek.com&gt;
Signed-off-by: Felix Fietkau &lt;nbd@nbd.name&gt;
Link: https://lore.kernel.org/r/20230314095956.62085-4-nbd@nbd.name
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Previously, fast xmit only worked on interface types where initially a
sta lookup is performed, and a cached header can be attached to the sta,
requiring only some fields to be updated at runtime.

This technique is not directly applicable for a mesh device type due
to the dynamic nature of the topology and protocol. There are more
addresses that need to be filled, and there is an extra header with a
dynamic length based on the addressing mode.

Change the code to cache entries contain a copy of the mesh subframe header +
bridge tunnel header, as well as an embedded struct ieee80211_fast_tx, which
contains the information for building the 802.11 header.

Add a mesh specific early fast xmit call, which looks up a cached entry and
adds only the mesh subframe header, before passing it over to the generic
fast xmit code.

To ensure the changes in network are reflected in these cached headers,
flush affected cached entries on path changes, as well as other conditions
that currently trigger a fast xmit check in other modes (key changes etc.)

This code is loosely based on a previous implementation by:
Sriram R &lt;quic_srirrama@quicinc.com&gt;

Cc: Sriram R &lt;quic_srirrama@quicinc.com&gt;
Signed-off-by: Ryder Lee &lt;ryder.lee@mediatek.com&gt;
Signed-off-by: Felix Fietkau &lt;nbd@nbd.name&gt;
Link: https://lore.kernel.org/r/20230314095956.62085-4-nbd@nbd.name
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: allow beacon protection HW offload</title>
<updated>2023-03-07T09:30:04+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2023-03-01T10:09:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d1b9bb6520fe0c295128229f5d3a9298127d5c8a'/>
<id>d1b9bb6520fe0c295128229f5d3a9298127d5c8a</id>
<content type='text'>
In case of beacon protection, check if the key was offloaded
to the hardware and in that case set control.hw_key so that
the encryption function will see it and only do the needed
steps that aren't done in hardware.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Link: https://lore.kernel.org/r/20230301115906.b2becd9a22fb.I6c0b9c50c6a481128ba912a11cb7afc92c4b6da7@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In case of beacon protection, check if the key was offloaded
to the hardware and in that case set control.hw_key so that
the encryption function will see it and only do the needed
steps that aren't done in hardware.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Link: https://lore.kernel.org/r/20230301115906.b2becd9a22fb.I6c0b9c50c6a481128ba912a11cb7afc92c4b6da7@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>wifi: mac80211: check key taint for beacon protection</title>
<updated>2023-03-07T09:29:53+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2023-03-01T10:09:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3ffcc659dc6fa84da7db57f56fd48756c5a60fba'/>
<id>3ffcc659dc6fa84da7db57f56fd48756c5a60fba</id>
<content type='text'>
This will likely never happen, but for completeness check
the key taint flag before using a key for beacon protection.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Link: https://lore.kernel.org/r/20230301115906.cf2c3fee6f1f.I2f19b3e04e31c99bed3c9dc71935bf513b2cd177@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This will likely never happen, but for completeness check
the key taint flag before using a key for beacon protection.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Gregory Greenman &lt;gregory.greenman@intel.com&gt;
Link: https://lore.kernel.org/r/20230301115906.cf2c3fee6f1f.I2f19b3e04e31c99bed3c9dc71935bf513b2cd177@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
