INFO: task syz-executor.2:22776 blocked for more than 143 seconds.
      Not tainted 6.8.0-rc6-syzkaller-02081-ga148f82c457f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:20984 pid:22776 tgid:22776 ppid:1      flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0x149/0x260 kernel/sched/core.c:6817
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6874
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a3/0xd70 kernel/locking/mutex.c:752
 del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
 kernfs_fop_write_iter+0x3a4/0x500 fs/kernfs/file.c:334
 call_write_iter include/linux/fs.h:2087 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xa81/0xcb0 fs/read_write.c:590
 ksys_write+0x1a0/0x2c0 fs/read_write.c:643
 do_syscall_64+0xf9/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f56d8c7caef
RSP: 002b:00007ffe2762b0e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f56d8c7caef
RDX: 0000000000000001 RSI: 00007ffe2762b130 RDI: 0000000000000005
RBP: 00007f56d8cca021 R08: 0000000000000000 R09: 00007ffe2762af37
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007ffe2762b130 R14: 00007f56d98d4620 R15: 0000000000000003
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
 #0: ffffffff8e130be0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614
5 locks held by kworker/u4:6/2442:
1 lock held by syslogd/4510:
 #0: ffff8880b953c958 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559
2 locks held by dhcpcd/4742:
 #0: ffff8881a3bb5678 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x780 net/netlink/af_netlink.c:2347
 #1: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0x5d3/0xe50 net/netlink/af_netlink.c:2265
2 locks held by getty/4823:
 #0: ffff88802a57d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201
3 locks held by kworker/1:5/5149:
 #0: ffff888014c78938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #0: ffff888014c78938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #1: ffffc90004b3fd20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #1: ffffc90004b3fd20 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #2: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by kworker/0:6/5216:
 #0: ffff888014c78938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #0: ffff888014c78938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #1: ffffc90005affd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #1: ffffc90005affd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #2: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276
2 locks held by kworker/u4:18/13313:
3 locks held by kworker/0:4/23235:
 #0: ffff888014c78938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #0: ffff888014c78938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #1: ffffc90013a87d20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #1: ffffc90013a87d20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #2: ffff88817fbeb240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1489
1 lock held by syz-executor.2/20898:
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: netdev_wait_allrefs_any net/core/dev.c:10497 [inline]
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x89e/0x1000 net/core/dev.c:10607
6 locks held by syz-executor.2/21081:
 #0: ffff88807b52c420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2794 [inline]
 #0: ffff88807b52c420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586
 #1: ffff888061a0f088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325
 #2: ffff888021d5eda0 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326
 #3: ffffffff8ecb83e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
 #4: ffff888044d390e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline]
 #4: ffff888044d390e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline]
 #4: ffff888044d390e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1292
 #5: ffff888044d3a250 (&devlink->lock_key#5){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672
4 locks held by syz-executor.2/22776:
 #0: ffff88807b52c420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2794 [inline]
 #0: ffff88807b52c420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586
 #1: ffff88819c2b7488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325
 #2: ffff888021d5eda0 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326
 #3: ffffffff8ecb83e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
4 locks held by syz-executor.2/24528:
 #0: ffff88807b52c420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2794 [inline]
 #0: ffff88807b52c420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586
 #1: ffff8881b019e888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325
 #2: ffff888021d5eda0 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326
 #3: ffffffff8ecb83e8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
1 lock held by syz-executor.2/26684:
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6595
1 lock held by syz-executor.0/26805:
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6595
3 locks held by kworker/u4:1/26808:
 #0: ffff888029b60938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #0: ffff888029b60938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #1: ffffc90012e8fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline]
 #1: ffffc90012e8fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706
 #2: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4193
1 lock held by syz-executor.1/26890:
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6595
1 lock held by syz-executor.3/26895:
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6595
1 lock held by syz-executor.3/26896:
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8f378f88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x842/0x10d0 net/core/rtnetlink.c:6595
2 locks held by syz-executor.4/26926:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc6-syzkaller-02081-ga148f82c457f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xfaf/0xff0 kernel/hung_task.c:379
 kthread+0x2ef/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:243
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 26926 Comm: syz-executor.4 Not tainted 6.8.0-rc6-syzkaller-02081-ga148f82c457f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:get_current arch/x86/include/asm/current.h:42 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:235 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp8+0x8/0x90 kernel/kcov.c:284
Code: 0a 20 c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 4c 8b 04 24 <65> 48 8b 0d 20 4f 70 7e 65 8b 05 21 4f 70 7e a9 00 01 ff 00 74 10
RSP: 0018:ffffc90013cef7a0 EFLAGS: 00000297
RAX: 0000000000000002 RBX: ffffc90013cef8d0 RCX: ffff888015b6bb80
RDX: ffff888015b6bb80 RSI: cff2f1feff6a7a24 RDI: c9671dfeff054590
RBP: c9671dfeff054590 R08: ffffffff8ab2ac16 R09: ffffffff8aa4cdda
R10: 0000000000000002 R11: ffffffff8ab2e950 R12: 00000000000080fe
R13: ffff88819c68b8a8 R14: cff2f1feff6a7a24 R15: 00000000000080fe
FS:  00007f3d770846c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555556c52788 CR3: 0000000073e3a000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 ipv6_addr_equal include/net/ipv6.h:673 [inline]
 __sctp_v6_cmp_addr+0x116/0x520 net/sctp/ipv6.c:643
 sctp_v6_cmp_addr+0x20/0xd0 net/sctp/ipv6.c:661
 sctp_bind_addr_state+0xd2/0x1b0 net/sctp/bind_addr.c:413
 sctp_copy_local_addr_list+0x2d7/0x500 net/sctp/protocol.c:162
 sctp_bind_addr_copy+0xad/0x3b0 net/sctp/bind_addr.c:56
 sctp_connect_new_asoc+0x2f3/0x6c0 net/sctp/socket.c:1094
 sctp_sendmsg_new_asoc net/sctp/socket.c:1692 [inline]
 sctp_sendmsg+0x219a/0x3520 net/sctp/socket.c:2003
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x1a6/0x270 net/socket.c:745
 __sys_sendto+0x3a4/0x4f0 net/socket.c:2191
 __do_sys_sendto net/socket.c:2203 [inline]
 __se_sys_sendto net/socket.c:2199 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2199
 do_syscall_64+0xf9/0x240
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7f3d7627dda9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3d770840c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f3d763abf80 RCX: 00007f3d7627dda9
RDX: 000000000000fee4 RSI: 0000000020847fff RDI: 0000000000000003
RBP: 00007f3d762ca47a R08: 000000002005ffe4 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f3d763abf80 R15: 00007fff8da35968
 </TASK>