INFO: task syz-executor.3:27758 blocked for more than 143 seconds. Not tainted 6.8.0-rc4-syzkaller-01524-g85badb2c008a #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:20984 pid:27758 tgid:27758 ppid:1 flags:0x00004006 Call Trace: 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 new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 kernfs_fop_write_iter+0x3a4/0x500 fs/kernfs/file.c:334 call_write_iter include/linux/fs.h:2085 [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: 0033:0x7f52f127caef RSP: 002b:00007ffd0979a4a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f52f127caef RDX: 0000000000000003 RSI: 00007ffd0979a4f0 RDI: 0000000000000005 RBP: 00007f52f12ca045 R08: 0000000000000000 R09: 00007ffd0979a2f7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 00007ffd0979a4f0 R14: 00007f52f1ed4620 R15: 0000000000000003 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 6 locks held by kworker/u4:6/2429: 1 lock held by klogd/4511: 1 lock held by dhcpcd/4736: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xde/0xc80 net/netlink/af_netlink.c:2211 2 locks held by getty/4828: #0: ffff88802f9c90a0 (&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/1:19/17561: #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90014247d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90014247d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by kworker/u4:1/27673: #0: ffff88802a8a3538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff88802a8a3538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90003befd20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90003befd20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4719 4 locks held by syz-executor.1/27752: #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2792 [inline] #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff888048955488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888023065008 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb6c28 (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.3/27758: #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2792 [inline] #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff88804ea55488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888023239e90 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb6c28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 7 locks held by syz-executor.2/27771: #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2792 [inline] #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff8881ca316c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888023239e90 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb6c28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 #4: ffff888074c500e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:990 [inline] #4: ffff888074c500e8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005 #5: ffff888074c56250 (&devlink->lock_key#6){+.+.}-{3:3}, at: nsim_drv_probe+0xcb/0xb80 drivers/net/netdevsim/dev.c:1534 #6: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:335 [inline] #6: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: nsim_create+0x357/0x480 drivers/net/netdevsim/netdev.c:401 4 locks held by syz-executor.4/27791: #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2792 [inline] #0: ffff88807480e420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x233/0xcb0 fs/read_write.c:586 #1: ffff888051573888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888023239e90 (kn->active#51){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8ecb6c28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x1b4/0x890 drivers/net/netdevsim/bus.c:166 1 lock held by syz-executor.1/27931: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.3/27935: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.2/27948: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.4/27968: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.1/28004: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.3/28009: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.2/28021: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.4/28040: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.0/28062: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:696 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x1b0 drivers/net/tun.c:3504 1 lock held by syz-executor.1/28069: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 1 lock held by syz-executor.3/28073: #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f376f08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6594 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc4-syzkaller-01524-g85badb2c008a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __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:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 20450 Comm: kworker/u4:8 Not tainted 6.8.0-rc4-syzkaller-01524-g85badb2c008a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: 0x0 (events_unbound) RIP: 0010:__schedule+0x2549/0x49f0 kernel/sched/core.c:6724 Code: 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 65 ed 82 f6 31 f6 83 7c 24 58 00 40 0f 95 c6 48 8b 3b <48> 8b 54 24 18 48 8b 4c 24 08 45 89 e8 e8 45 9a 27 f6 65 ff 0d 26 RSP: 0018:ffffc90014b0fb80 EFLAGS: 00000046 RAX: 1ffff1100fa184db RBX: ffff88807d0c26d8 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90014b0fd98 R08: ffffffff8f85d36f R09: 1ffffffff1f0ba6d R10: dffffc0000000000 R11: fffffbfff1f0ba6e R12: ffffc90014b0fca0 R13: 0000000000000402 R14: dffffc0000000000 R15: ffff88802a2e8000 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000558967552d90 CR3: 000000000df32000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 worker_thread+0xc26/0x1000 kernel/workqueue.c:2802 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:242