[ 743.582725] nipa-hw-worker: drivers/net:napi_threaded.py: timed out
[ 743.585425] nipa-hw-worker: [4/36] Retrying drivers/net:napi_threaded.py
[ 743.720862] kselftest: Running tests in drivers/net
[ 989.731988] INFO: task python3:4725 blocked for more than 122 seconds.
[ 989.740210] Not tainted 7.0.0-rc3-nzyv-g9e6c4c06d9c2 #1
[ 989.747449] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 989.757040] task:python3 state:D stack:25312 pid:4725 tgid:4725 ppid:4724 task_flags:0x400100 flags:0x00080002
[ 989.770247] Call Trace:
[ 989.773785]
[ 989.776932] __schedule+0xad9/0x1490
[ 989.781748] ? io_schedule_timeout+0x130/0x130
[ 989.787533] ? find_held_lock+0x2b/0x80
[ 989.792638] ? __lock_release.isra.0+0x59/0x170
[ 989.798522] schedule+0xd4/0x260
[ 989.802932] schedule_preempt_disabled+0x18/0x30
[ 989.808911] __mutex_lock+0xd76/0x1f20
[ 989.813913] ? threaded_store+0x132/0x220
[ 989.819210] ? ww_mutex_lock+0x160/0x160
[ 989.824407] ? selinux_inode_free_security+0x310/0x310
[ 989.830974] ? cap_capable+0x1ed/0x3f0
[ 989.835986] ? sysfs_file_ops+0x140/0x140
[ 989.841292] ? threaded_store+0x132/0x220
[ 989.846587] threaded_store+0x132/0x220
[ 989.851688] ? tx_maxrate_store+0x4e0/0x4e0
[ 989.857177] ? sysfs_file_ops+0x140/0x140
[ 989.862473] ? sysfs_file_kobj+0xbd/0x1e0
[ 989.867767] ? sysfs_kf_write+0x65/0x160
[ 989.872968] kernfs_fop_write_iter+0x335/0x510
[ 989.878752] ? kernfs_ops+0xf0/0xf0
[ 989.883463] new_sync_write+0x308/0x6f0
[ 989.888568] ? new_sync_read+0x6f0/0x6f0
[ 989.893767] ? lock_acquire.part.0+0xbc/0x260
[ 989.899453] ? ksys_write+0xff/0x200
[ 989.904262] vfs_write+0x62a/0x980
[ 989.908875] ksys_write+0xff/0x200
[ 989.913486] ? __ia32_sys_read+0xc0/0xc0
[ 989.918681] ? kernfs_fop_llseek+0x160/0x1f0
[ 989.924271] ? rcu_is_watching+0x15/0xd0
[ 989.929472] do_syscall_64+0xf3/0x5e0
[ 989.934379] ? exc_page_fault+0x9e/0xb0
[ 989.939481] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 989.945949] RIP: 0033:0x7f3c1c3a0c5e
[ 989.950760] RSP: 002b:00007ffdff1f6b70 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 989.960056] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f3c1c3a0c5e
[ 989.968861] RDX: 0000000000000001 RSI: 000056053131acd0 RDI: 0000000000000007
[ 989.977666] RBP: 00007ffdff1f6b80 R08: 0000000000000000 R09: 0000000000000000
[ 989.986474] R10: 0000000000000000 R11: 0000000000000202 R12: 00007f3c1c23be80
[ 989.995274] R13: 000056053131acd0 R14: 0000000000000007 R15: 00007f3c1caa1b98
[ 990.004088]
[ 990.007371] INFO: task python3:4725 is blocked on a mutex likely owned by task python3:2740.
[ 990.017643] task:python3 state:D stack:25312 pid:2740 tgid:2740 ppid:2739 task_flags:0x400100 flags:0x00080802
[ 990.030844] Call Trace:
[ 990.034381]
[ 990.037528] __schedule+0xad9/0x1490
[ 990.042340] ? io_schedule_timeout+0x130/0x130
[ 990.048114] ? find_held_lock+0x2b/0x80
[ 990.053219] ? __try_to_del_timer_sync+0x154/0x1f0
[ 990.059397] schedule+0xd4/0x260
[ 990.063814] schedule_timeout+0x103/0x260
[ 990.069115] ? rcu_is_watching+0x15/0xd0
[ 990.074311] ? hrtimer_nanosleep_restart+0x180/0x180
[ 990.080681] ? hrtimers_cpu_dying+0x250/0x250
[ 990.086372] ? ww_mutex_lock+0x160/0x160
[ 990.091570] msleep+0x1b/0x30
[ 990.095694] napi_set_threaded+0x376/0x410
[ 990.101091] ? napi_resume_irqs+0x1a0/0x1a0
[ 990.106575] netif_set_threaded+0x254/0x400
[ 990.112060] ? sysfs_file_ops+0x140/0x140
[ 990.117356] threaded_store+0x1bb/0x220
[ 990.122458] ? tx_maxrate_store+0x4e0/0x4e0
[ 990.127948] ? sysfs_file_ops+0x140/0x140
[ 990.133244] ? sysfs_file_kobj+0xbd/0x1e0
[ 990.138538] ? sysfs_kf_write+0x65/0x160
[ 990.143739] kernfs_fop_write_iter+0x335/0x510
[ 990.149523] ? kernfs_ops+0xf0/0xf0
[ 990.154235] new_sync_write+0x308/0x6f0
[ 990.159327] ? new_sync_read+0x6f0/0x6f0
[ 990.164528] ? lock_acquire.part.0+0xbc/0x260
[ 990.170215] ? ksys_write+0xff/0x200
[ 990.175026] vfs_write+0x62a/0x980
[ 990.179631] ksys_write+0xff/0x200
[ 990.184242] ? __ia32_sys_read+0xc0/0xc0
[ 990.189440] ? kernfs_fop_llseek+0x160/0x1f0
[ 990.195030] ? rcu_is_watching+0x15/0xd0
[ 990.200220] do_syscall_64+0xf3/0x5e0
[ 990.205125] ? irq_exit_rcu+0x39/0xf0
[ 990.210033] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 990.216490] RIP: 0033:0x7f29fbbacc5e
[ 990.221300] RSP: 002b:00007ffdb21ad820 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 990.230587] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f29fbbacc5e
[ 990.239392] RDX: 0000000000000001 RSI: 00005597f3334cd0 RDI: 0000000000000007
[ 990.248196] RBP: 00007ffdb21ad830 R08: 0000000000000000 R09: 0000000000000000
[ 990.257002] R10: 0000000000000000 R11: 0000000000000202 R12: 00007f29fba47e80
[ 990.265806] R13: 00005597f3334cd0 R14: 0000000000000007 R15: 00007f29fb9d6480
[ 990.274618]
[ 990.277877] \x0aShowing all locks held in the system:
[ 990.286415] 1 lock held by khungtaskd/185:
[ 990.291810] #0: ffffffffa34cde20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire.constprop.0+0x7/0x30
[ 990.303298] 4 locks held by python3/2740:
[ 990.308595] #0: ff1100012e3093f8 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xff/0x200
[ 990.318384] #1: ff110001ea8f5088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x247/0x510
[ 990.329346] #2: ff110001222450f0 (kn->active#127){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x510
[ 990.340496] #3: ff110001221e9cb8 (&dev->lock){+.+.}-{4:4}, at: threaded_store+0x132/0x220
[ 990.350598] 4 locks held by python3/4725:
[ 990.355893] #0: ff1100012e3093f8 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xff/0x200
[ 990.365684] #1: ff1100017f315c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x247/0x510
[ 990.376646] #2: ff110001222450f0 (kn->active#127){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x510
[ 990.387805] #3: ff110001221e9cb8 (&dev->lock){+.+.}-{4:4}, at: threaded_store+0x132/0x220
[ 990.397894]
[ 990.400357] =============================================\x0a
[ 1112.614300] INFO: task python3:4725 blocked for more than 245 seconds.
[ 1112.622448] Not tainted 7.0.0-rc3-nzyv-g9e6c4c06d9c2 #1
[ 1112.629701] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1112.639290] task:python3 state:D stack:25312 pid:4725 tgid:4725 ppid:4724 task_flags:0x400100 flags:0x00080002
[ 1112.652496] Call Trace:
[ 1112.656038]
[ 1112.659183] __schedule+0xad9/0x1490
[ 1112.663999] ? io_schedule_timeout+0x130/0x130
[ 1112.669786] ? find_held_lock+0x2b/0x80
[ 1112.674890] ? __lock_release.isra.0+0x59/0x170
[ 1112.680769] schedule+0xd4/0x260
[ 1112.685187] schedule_preempt_disabled+0x18/0x30
[ 1112.691166] __mutex_lock+0xd76/0x1f20
[ 1112.696172] ? threaded_store+0x132/0x220
[ 1112.701471] ? ww_mutex_lock+0x160/0x160
[ 1112.706672] ? selinux_inode_free_security+0x310/0x310
[ 1112.713243] ? cap_capable+0x1ed/0x3f0
[ 1112.718255] ? sysfs_file_ops+0x140/0x140
[ 1112.723558] ? threaded_store+0x132/0x220
[ 1112.728854] threaded_store+0x132/0x220
[ 1112.733957] ? tx_maxrate_store+0x4e0/0x4e0
[ 1112.739449] ? sysfs_file_ops+0x140/0x140
[ 1112.744748] ? sysfs_file_kobj+0xbd/0x1e0
[ 1112.750044] ? sysfs_kf_write+0x65/0x160
[ 1112.755243] kernfs_fop_write_iter+0x335/0x510
[ 1112.761027] ? kernfs_ops+0xf0/0xf0
[ 1112.765741] new_sync_write+0x308/0x6f0
[ 1112.770846] ? new_sync_read+0x6f0/0x6f0
[ 1112.776048] ? lock_acquire.part.0+0xbc/0x260
[ 1112.781735] ? ksys_write+0xff/0x200
[ 1112.786546] vfs_write+0x62a/0x980
[ 1112.791161] ksys_write+0xff/0x200
[ 1112.795766] ? __ia32_sys_read+0xc0/0xc0
[ 1112.800963] ? kernfs_fop_llseek+0x160/0x1f0
[ 1112.806555] ? rcu_is_watching+0x15/0xd0
[ 1112.811757] do_syscall_64+0xf3/0x5e0
[ 1112.816662] ? exc_page_fault+0x9e/0xb0
[ 1112.821766] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 1112.828233] RIP: 0033:0x7f3c1c3a0c5e
[ 1112.833045] RSP: 002b:00007ffdff1f6b70 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 1112.842343] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f3c1c3a0c5e
[ 1112.851154] RDX: 0000000000000001 RSI: 000056053131acd0 RDI: 0000000000000007
[ 1112.859964] RBP: 00007ffdff1f6b80 R08: 0000000000000000 R09: 0000000000000000
[ 1112.868774] R10: 0000000000000000 R11: 0000000000000202 R12: 00007f3c1c23be80
[ 1112.877583] R13: 000056053131acd0 R14: 0000000000000007 R15: 00007f3c1caa1b98
[ 1112.886398]
[ 1112.889691] INFO: task python3:4725 is blocked on a mutex likely owned by task python3:2740.
[ 1112.899958] task:python3 state:D stack:25312 pid:2740 tgid:2740 ppid:2739 task_flags:0x400100 flags:0x00080802
[ 1112.913161] Call Trace:
[ 1112.916700]
[ 1112.919851] __schedule+0xad9/0x1490
[ 1112.924664] ? io_schedule_timeout+0x130/0x130
[ 1112.930448] ? find_held_lock+0x2b/0x80
[ 1112.935545] ? __try_to_del_timer_sync+0x154/0x1f0
[ 1112.941725] schedule+0xd4/0x260
[ 1112.946144] schedule_timeout+0x103/0x260
[ 1112.951442] ? rcu_is_watching+0x15/0xd0
[ 1112.956641] ? hrtimer_nanosleep_restart+0x180/0x180
[ 1112.963013] ? hrtimers_cpu_dying+0x250/0x250
[ 1112.968702] ? ww_mutex_lock+0x160/0x160
[ 1112.973901] msleep+0x1b/0x30
[ 1112.978027] napi_set_threaded+0x376/0x410
[ 1112.983416] ? napi_resume_irqs+0x1a0/0x1a0
[ 1112.988910] netif_set_threaded+0x254/0x400
[ 1112.994406] ? sysfs_file_ops+0x140/0x140
[ 1112.999701] threaded_store+0x1bb/0x220
[ 1113.004804] ? tx_maxrate_store+0x4e0/0x4e0
[ 1113.010295] ? sysfs_file_ops+0x140/0x140
[ 1113.015592] ? sysfs_file_kobj+0xbd/0x1e0
[ 1113.020887] ? sysfs_kf_write+0x65/0x160
[ 1113.026088] kernfs_fop_write_iter+0x335/0x510
[ 1113.031874] ? kernfs_ops+0xf0/0xf0
[ 1113.036587] new_sync_write+0x308/0x6f0
[ 1113.041689] ? new_sync_read+0x6f0/0x6f0
[ 1113.046890] ? lock_acquire.part.0+0xbc/0x260
[ 1113.052578] ? ksys_write+0xff/0x200
[ 1113.057389] vfs_write+0x62a/0x980
[ 1113.062002] ksys_write+0xff/0x200
[ 1113.066615] ? __ia32_sys_read+0xc0/0xc0
[ 1113.071812] ? kernfs_fop_llseek+0x160/0x1f0
[ 1113.077403] ? rcu_is_watching+0x15/0xd0
[ 1113.082602] do_syscall_64+0xf3/0x5e0
[ 1113.087507] ? irq_exit_rcu+0x39/0xf0
[ 1113.092416] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 1113.098885] RIP: 0033:0x7f29fbbacc5e
[ 1113.103693] RSP: 002b:00007ffdb21ad820 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 1113.112988] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f29fbbacc5e
[ 1113.121796] RDX: 0000000000000001 RSI: 00005597f3334cd0 RDI: 0000000000000007
[ 1113.130606] RBP: 00007ffdb21ad830 R08: 0000000000000000 R09: 0000000000000000
[ 1113.139415] R10: 0000000000000000 R11: 0000000000000202 R12: 00007f29fba47e80
[ 1113.148224] R13: 00005597f3334cd0 R14: 0000000000000007 R15: 00007f29fb9d6480
[ 1113.157040]
[ 1113.160304] \x0aShowing all locks held in the system:
[ 1113.168846] 1 lock held by khungtaskd/185:
[ 1113.174241] #0: ffffffffa34cde20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire.constprop.0+0x7/0x30
[ 1113.185722] 4 locks held by python3/2740:
[ 1113.191017] #0: ff1100012e3093f8 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xff/0x200
[ 1113.200810] #1: ff110001ea8f5088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x247/0x510
[ 1113.211775] #2: ff110001222450f0 (kn->active#127){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x510
[ 1113.222934] #3: ff110001221e9cb8 (&dev->lock){+.+.}-{4:4}, at: threaded_store+0x132/0x220
[ 1113.233034] 4 locks held by python3/4725:
[ 1113.238327] #0: ff1100012e3093f8 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xff/0x200
[ 1113.248117] #1: ff1100017f315c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x247/0x510
[ 1113.259080] #2: ff110001222450f0 (kn->active#127){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x510
[ 1113.270238] #3: ff110001221e9cb8 (&dev->lock){+.+.}-{4:4}, at: threaded_store+0x132/0x220
[ 1113.280322]
[ 1113.282789] =============================================\x0a
[ 1235.494584] INFO: task python3:4725 blocked for more than 368 seconds.
[ 1235.502731] Not tainted 7.0.0-rc3-nzyv-g9e6c4c06d9c2 #1
[ 1235.509982] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1235.519570] task:python3 state:D stack:25312 pid:4725 tgid:4725 ppid:4724 task_flags:0x400100 flags:0x00080002
[ 1235.532773] Call Trace:
[ 1235.536313]
[ 1235.539461] __schedule+0xad9/0x1490
[ 1235.544274] ? io_schedule_timeout+0x130/0x130
[ 1235.550058] ? find_held_lock+0x2b/0x80
[ 1235.555164] ? __lock_release.isra.0+0x59/0x170
[ 1235.561049] schedule+0xd4/0x260
[ 1235.565466] schedule_preempt_disabled+0x18/0x30
[ 1235.571446] __mutex_lock+0xd76/0x1f20
[ 1235.576440] ? threaded_store+0x132/0x220
[ 1235.581729] ? ww_mutex_lock+0x160/0x160
[ 1235.586927] ? selinux_inode_free_security+0x310/0x310
[ 1235.593496] ? cap_capable+0x1ed/0x3f0
[ 1235.598504] ? sysfs_file_ops+0x140/0x140
[ 1235.603800] ? threaded_store+0x132/0x220
[ 1235.609095] threaded_store+0x132/0x220
[ 1235.614200] ? tx_maxrate_store+0x4e0/0x4e0
[ 1235.619692] ? sysfs_file_ops+0x140/0x140
[ 1235.624986] ? sysfs_file_kobj+0xbd/0x1e0
[ 1235.630282] ? sysfs_kf_write+0x65/0x160
[ 1235.635479] kernfs_fop_write_iter+0x335/0x510
[ 1235.641261] ? kernfs_ops+0xf0/0xf0
[ 1235.645970] new_sync_write+0x308/0x6f0
[ 1235.651073] ? new_sync_read+0x6f0/0x6f0
[ 1235.656275] ? lock_acquire.part.0+0xbc/0x260
[ 1235.661962] ? ksys_write+0xff/0x200
[ 1235.666773] vfs_write+0x62a/0x980
[ 1235.671388] ksys_write+0xff/0x200
[ 1235.676002] ? __ia32_sys_read+0xc0/0xc0
[ 1235.681198] ? kernfs_fop_llseek+0x160/0x1f0
[ 1235.686786] ? rcu_is_watching+0x15/0xd0
[ 1235.691987] do_syscall_64+0xf3/0x5e0
[ 1235.696883] ? exc_page_fault+0x9e/0xb0
[ 1235.701982] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 1235.708449] RIP: 0033:0x7f3c1c3a0c5e
[ 1235.713257] RSP: 002b:00007ffdff1f6b70 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 1235.722555] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f3c1c3a0c5e
[ 1235.731360] RDX: 0000000000000001 RSI: 000056053131acd0 RDI: 0000000000000007
[ 1235.740165] RBP: 00007ffdff1f6b80 R08: 0000000000000000 R09: 0000000000000000
[ 1235.748970] R10: 0000000000000000 R11: 0000000000000202 R12: 00007f3c1c23be80
[ 1235.757776] R13: 000056053131acd0 R14: 0000000000000007 R15: 00007f3c1caa1b98
[ 1235.766588]
[ 1235.769866] INFO: task python3:4725 is blocked on a mutex likely owned by task python3:2740.
[ 1235.780138] task:python3 state:D stack:25312 pid:2740 tgid:2740 ppid:2739 task_flags:0x400100 flags:0x00080802
[ 1235.793337] Call Trace:
[ 1235.796876]
[ 1235.800024] __schedule+0xad9/0x1490
[ 1235.804832] ? io_schedule_timeout+0x130/0x130
[ 1235.810614] ? find_held_lock+0x2b/0x80
[ 1235.815714] ? __try_to_del_timer_sync+0x154/0x1f0
[ 1235.821894] schedule+0xd4/0x260
[ 1235.826313] schedule_timeout+0x103/0x260
[ 1235.831611] ? rcu_is_watching+0x15/0xd0
[ 1235.836808] ? hrtimer_nanosleep_restart+0x180/0x180
[ 1235.843175] ? hrtimers_cpu_dying+0x250/0x250
[ 1235.848864] ? ww_mutex_lock+0x160/0x160
[ 1235.854051] msleep+0x1b/0x30
[ 1235.858174] napi_set_threaded+0x376/0x410
[ 1235.863569] ? napi_resume_irqs+0x1a0/0x1a0
[ 1235.869064] netif_set_threaded+0x254/0x400
[ 1235.874556] ? sysfs_file_ops+0x140/0x140
[ 1235.879852] threaded_store+0x1bb/0x220
[ 1235.884951] ? tx_maxrate_store+0x4e0/0x4e0
[ 1235.890444] ? sysfs_file_ops+0x140/0x140
[ 1235.895739] ? sysfs_file_kobj+0xbd/0x1e0
[ 1235.901035] ? sysfs_kf_write+0x65/0x160
[ 1235.906233] kernfs_fop_write_iter+0x335/0x510
[ 1235.912016] ? kernfs_ops+0xf0/0xf0
[ 1235.916727] new_sync_write+0x308/0x6f0
[ 1235.921830] ? new_sync_read+0x6f0/0x6f0
[ 1235.927029] ? lock_acquire.part.0+0xbc/0x260
[ 1235.932713] ? ksys_write+0xff/0x200
[ 1235.937526] vfs_write+0x62a/0x980
[ 1235.942138] ksys_write+0xff/0x200
[ 1235.946753] ? __ia32_sys_read+0xc0/0xc0
[ 1235.951953] ? kernfs_fop_llseek+0x160/0x1f0
[ 1235.957534] ? rcu_is_watching+0x15/0xd0
[ 1235.962732] do_syscall_64+0xf3/0x5e0
[ 1235.967638] ? irq_exit_rcu+0x39/0xf0
[ 1235.972535] entry_SYSCALL_64_after_hwframe+0x4b/0x53
[ 1235.979002] RIP: 0033:0x7f29fbbacc5e
[ 1235.983809] RSP: 002b:00007ffdb21ad820 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 1235.993104] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f29fbbacc5e
[ 1236.001910] RDX: 0000000000000001 RSI: 00005597f3334cd0 RDI: 0000000000000007
[ 1236.010716] RBP: 00007ffdb21ad830 R08: 0000000000000000 R09: 0000000000000000
[ 1236.019524] R10: 0000000000000000 R11: 0000000000000202 R12: 00007f29fba47e80
[ 1236.028331] R13: 00005597f3334cd0 R14: 0000000000000007 R15: 00007f29fb9d6480
[ 1236.037145]
[ 1236.040407] \x0aShowing all locks held in the system:
[ 1236.048944] 1 lock held by khungtaskd/185:
[ 1236.054338] #0: ffffffffa34cde20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire.constprop.0+0x7/0x30
[ 1236.065815] 4 locks held by python3/2740:
[ 1236.071109] #0: ff1100012e3093f8 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xff/0x200
[ 1236.080899] #1: ff110001ea8f5088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x247/0x510
[ 1236.091862] #2: ff110001222450f0 (kn->active#127){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x510
[ 1236.103017] #3: ff110001221e9cb8 (&dev->lock){+.+.}-{4:4}, at: threaded_store+0x132/0x220
[ 1236.113110] 4 locks held by python3/4725:
[ 1236.118401] #0: ff1100012e3093f8 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xff/0x200
[ 1236.128189] #1: ff1100017f315c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x247/0x510
[ 1236.139147] #2: ff110001222450f0 (kn->active#127){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x510
[ 1236.150306] #3: ff110001221e9cb8 (&dev->lock){+.+.}-{4:4}, at: threaded_store+0x132/0x220
[ 1236.160398]
[ 1236.162864] =============================================\x0a