syzbot

INFO: task syz-executor:6700 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:6700  tgid:6700  ppid:6697   task_flags:0x400140 flags:0x00800010
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:742 (T)
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1250/0x2a7c kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6960
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7017
 __mutex_lock_common+0xd04/0x2678 kernel/locking/mutex.c:692
 __mutex_lock kernel/locking/mutex.c:776 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:828
 device_lock include/linux/device.h:895 [inline]
 device_del+0xa4/0x808 drivers/base/core.c:3840
 device_unregister+0x2c/0xf4 drivers/base/core.c:3919
 nsim_bus_dev_del drivers/net/netdevsim/bus.c:483 [inline]
 del_device_store+0x27c/0x31c drivers/net/netdevsim/bus.c:244
 bus_attr_store+0x80/0xa4 drivers/base/bus.c:172
 sysfs_kf_write+0x1a8/0x23c fs/sysfs/file.c:142
 kernfs_fop_write_iter+0x33c/0x4d0 fs/kernfs/file.c:352
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x540/0xa3c fs/read_write.c:686
 ksys_write+0x120/0x210 fs/read_write.c:738
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __arm64_sys_write+0x7c/0x90 fs/read_write.c:746
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x254 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x26c arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
1 lock held by kthreadd/2:
1 lock held by khungtaskd/32:
 #0: ffff80008fa5b6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
3 locks held by kworker/u8:3/42:
1 lock held by pr/ttyAMA-1/43:
5 locks held by kworker/u8:4/239:
3 locks held by kworker/u8:5/409:
3 locks held by kworker/u8:6/527:
4 locks held by kworker/u8:7/688:
 #0: ffff0000c0032148 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009db67be0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
 #3: ffff0000ce558788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6363 [inline]
 #3: ffff0000ce558788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_leave_invalid_chans net/wireless/reg.c:2441 [inline]
 #3: ffff0000ce558788 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: reg_check_chans_work+0x114/0xdf0 net/wireless/reg.c:2456
3 locks held by kworker/u8:8/1075:
7 locks held by kworker/u8:9/1330:
3 locks held by kworker/u8:10/1697:
3 locks held by kworker/u8:11/1844:
2 locks held by kworker/u8:12/3251:
3 locks held by kworker/u8:13/3545:
3 locks held by kworker/u8:14/3590:
 #0: ffff0000d3e9b148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a3757be0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
2 locks held by kworker/u8:15/4344:
3 locks held by kworker/u8:16/4513:
4 locks held by kworker/u8:17/5573:
 #0: ffff0000c1ff2948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009cad7be0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000db85e0e0 (&type->s_umount_key#30){++++}-{4:4}, at: super_trylock_shared+0x24/0xdc fs/super.c:563
 #3: ffff0000db860b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
 #3: ffff0000db860b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1820 [inline]
 #3: ffff0000db860b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x150/0x2a0 fs/ext4/inode.c:3025
6 locks held by kworker/u8:18/5743:
 #0: ffff0000c1843148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff80009ca57be0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff800092ad79d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf0/0x638 net/core/net_namespace.c:670
 #3: ffff0000d8ba70e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #3: ffff0000d8ba70e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
 #3: ffff0000d8ba70e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0xe4/0x380 net/devlink/core.c:506
 #4: ffff0000d4788250 (&devlink->lock_key){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
 #4: ffff0000d4788250 (&devlink->lock_key){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
 #4: ffff0000d4788250 (&devlink->lock_key){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0xf0/0x380 net/devlink/core.c:506
 #5: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
1 lock held by klogd/6197:
3 locks held by udevd/6208:
2 locks held by dhcpcd/6262:
4 locks held by dhcpcd/6263:
2 locks held by getty/6350:
 #0: ffff0000db3d80a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff800099f1e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfc8 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/6699:
 #0: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
5 locks held by syz-executor/6700:
 #0: ffff0000db9a2420 (sb_writers#6){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2681 [inline]
 #0: ffff0000db9a2420 (sb_writers#6){.+.+}-{0:0}, at: vfs_write+0x24c/0xa3c fs/read_write.c:682
 #1: ffff0000c7017088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1b4/0x4d0 fs/kernfs/file.c:343
 #2: ffff0000cdd63a58 (kn->active#55){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff0000cdd63a58 (kn->active#55){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1f4/0x4d0 fs/kernfs/file.c:344
 #3: ffff800091bf3c68 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
 #4: ffff0000d8ba70e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #4: ffff0000d8ba70e8 (&dev->mutex){....}-{4:4}, at: device_del+0xa4/0x808 drivers/base/core.c:3840
3 locks held by syz-executor/6702:
1 lock held by syz-executor/6709:
1 lock held by syz-executor/6713:
 #0: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffff800092ae4928 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x71c/0x15e8 net/core/rtnetlink.c:4071
3 locks held by kworker/u8:19/6807:
2 locks held by kworker/u8:21/6815:
3 locks held by syz-executor/6818:
3 locks held by kworker/u8:23/6822:

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