syzbot

INFO: task syz-executor:6696 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:6696  tgid:6696  ppid:1      task_flags:0x400140 flags:0x00000001
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7083
 __mutex_lock_common+0xd04/0x2678 kernel/locking/mutex.c:676
 __mutex_lock kernel/locking/mutex.c:760 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812
 del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
 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+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:746
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
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:1      task_flags:0x400140 flags:0x00000001
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7083
 __mutex_lock_common+0xd04/0x2678 kernel/locking/mutex.c:676
 __mutex_lock kernel/locking/mutex.c:760 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812
 del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
 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+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:746
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
INFO: task syz-executor:6701 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:6701  tgid:6701  ppid:6699   task_flags:0x400140 flags:0x00000010
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7083
 __mutex_lock_common+0xd04/0x2678 kernel/locking/mutex.c:676
 __mutex_lock kernel/locking/mutex.c:760 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812
 device_lock include/linux/device.h:914 [inline]
 device_del+0xa4/0x808 drivers/base/core.c:3840
 device_unregister+0x2c/0xcc 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+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:746
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
INFO: task syz-executor:6713 blocked for more than 145 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:6713  tgid:6713  ppid:6710   task_flags:0x400140 flags:0x00800000
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:741 (T)
 context_switch kernel/sched/core.c:5325 [inline]
 __schedule+0x13b0/0x2864 kernel/sched/core.c:6929
 __schedule_loop kernel/sched/core.c:7011 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:7026
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7083
 __mutex_lock_common+0xd04/0x2678 kernel/locking/mutex.c:676
 __mutex_lock kernel/locking/mutex.c:760 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:812
 del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
 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+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x5c/0x254 arch/arm64/kernel/entry-common.c:746
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:765
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
3 locks held by kworker/u8:0/12:
1 lock held by khungtaskd/32:
 #0: ffff80008f76b5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
8 locks held by kworker/u8:4/599:
4 locks held by kworker/1:2/1857:
3 locks held by kworker/u8:6/2031:
1 lock held by klogd/6180:
2 locks held by udevd/6191:
3 locks held by dhcpcd/6245:
1 lock held by dhcpcd/6246:
2 locks held by getty/6337:
 #0: ffff0000d29440a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009bb1b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/6591:
4 locks held by syz-executor/6696:
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3111 [inline]
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: vfs_write+0x24c/0xa3c fs/read_write.c:682
 #1: ffff0000f3eac488 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1b4/0x4d0 fs/kernfs/file.c:343
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1f4/0x4d0 fs/kernfs/file.c:344
 #3: ffff8000918a3da8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
4 locks held by syz-executor/6700:
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3111 [inline]
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: vfs_write+0x24c/0xa3c fs/read_write.c:682
 #1: ffff0000f406a888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1b4/0x4d0 fs/kernfs/file.c:343
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1f4/0x4d0 fs/kernfs/file.c:344
 #3: ffff8000918a3da8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
5 locks held by syz-executor/6701:
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3111 [inline]
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: vfs_write+0x24c/0xa3c fs/read_write.c:682
 #1: ffff0000f3c3d088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1b4/0x4d0 fs/kernfs/file.c:343
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1f4/0x4d0 fs/kernfs/file.c:344
 #3: ffff8000918a3da8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
 #4: ffff0000d347c0e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
 #4: ffff0000d347c0e8 (&dev->mutex){....}-{4:4}, at: device_del+0xa4/0x808 drivers/base/core.c:3840
5 locks held by kworker/1:4/6704:
4 locks held by syz-executor/6713:
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3111 [inline]
 #0: ffff0000d82d8420 (sb_writers#6){.+.+}-{0:0}, at: vfs_write+0x24c/0xa3c fs/read_write.c:682
 #1: ffff0000f42ef088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1b4/0x4d0 fs/kernfs/file.c:343
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff0000c58d3698 (kn->active#55){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x1f4/0x4d0 fs/kernfs/file.c:344
 #3: ffff8000918a3da8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd4/0x31c drivers/net/netdevsim/bus.c:234
3 locks held by kworker/u8:11/6767:
 #0: ffff0000d2e81148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3237
 #1: ffff8000a3747be0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3237
 #2: ffff8000928570a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80
5 locks held by kworker/u8:12/6769:
2 locks held by syz-executor/6774:

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