======================================================
WARNING: possible circular locking dependency detected
6.13.0-syzkaller-08291-g805ba04cb7cc #0 Not tainted
------------------------------------------------------
kworker/u32:7/1141 is trying to acquire lock:
ffffffff8fef6168 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_acquire_if_cleanup_net net/core/dev.c:10272 [inline]
ffffffff8fef6168 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x1a51/0x21a0 net/core/dev.c:11792

but task is already holding lock:

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:
-> #1 (&rdev->wiphy.mtx){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
       init_mac80211_hwsim+0x432/0x8c0 drivers/net/wireless/virtual/mac80211_hwsim.c:6910
       do_one_initcall+0x128/0x700 init/main.c:1257
       do_initcall_level init/main.c:1319 [inline]
       do_initcalls init/main.c:1335 [inline]
       do_basic_setup init/main.c:1354 [inline]
       kernel_init_freeable+0x5c7/0x900 init/main.c:1568
       kernel_init+0x1c/0x2b0 init/main.c:1457
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
-> #0 (rtnl_mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
       unregister_netdevice_many net/core/dev.c:11875 [inline]
       unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11741
       ops_exit_list+0xb0/0x180 net/core/net_namespace.c:172
       cleanup_net+0x5c6/0xbf0 net/core/net_namespace.c:652
       process_scheduled_works kernel/workqueue.c:3317 [inline]
       worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398

other info that might help us debug this:


       CPU0                    CPU1
  lock(&rdev->wiphy.mtx);
                               lock(rtnl_mutex);
  lock(rtnl_mutex);
 *** DEADLOCK ***

4 locks held by kworker/u32:7/1141:
 #2: ffffffff8fee0550 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xca/0xbf0 net/core/net_namespace.c:606
 #3: ffff888038990768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6061 [inline]
 #3: ffff888038990768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ieee80211_remove_interfaces+0xf1/0x720 net/mac80211/iface.c:2280

stack backtrace:
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain kernel/locking/lockdep.c:3906 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
 rtnl_acquire_if_cleanup_net net/core/dev.c:10272 [inline]
 unregister_netdevice_many_notify+0x1a51/0x21a0 net/core/dev.c:11792
 unregister_netdevice_many net/core/dev.c:11875 [inline]
 unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11741
 unregister_netdevice include/linux/netdevice.h:3329 [inline]
 _cfg80211_unregister_wdev+0x64b/0x830 net/wireless/core.c:1251
 ieee80211_remove_interfaces+0x34f/0x720 net/mac80211/iface.c:2305
 ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1681
 mac80211_hwsim_del_radio drivers/net/wireless/virtual/mac80211_hwsim.c:5664 [inline]
 hwsim_exit_net+0x3ad/0x7d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6544
 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:172
 cleanup_net+0x5c6/0xbf0 net/core/net_namespace.c:652
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3317 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398
 kthread+0x3af/0x750 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>