INFO: task syz.0.2602:13285 blocked for more than 145 seconds. Not tainted 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2602 state:D stack:27616 pid:13285 tgid:13284 ppid:12700 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xe37/0x5490 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2557 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3de/0x5f0 kernel/sched/completion.c:116 __flush_work+0x776/0xc30 kernel/workqueue.c:4212 __cancel_work_sync+0x10c/0x130 kernel/workqueue.c:4332 uhid_dev_destroy drivers/hid/uhid.c:584 [inline] uhid_char_write+0xc0b/0x10c0 drivers/hid/uhid.c:761 vfs_write+0x29a/0x1140 fs/read_write.c:588 ksys_write+0x1f8/0x260 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efeb1d79eb9 RSP: 002b:00007efeb2b52038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007efeb1f15f80 RCX: 00007efeb1d79eb9 RDX: 0000000000000004 RSI: 00000000200011c0 RDI: 0000000000000003 RBP: 00007efeb1de793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007efeb1f15f80 R15: 00007ffc9da14a38 Showing all locks held in the system: 3 locks held by kworker/0:0/8: 1 lock held by khungtaskd/31: #0: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8ddb9fe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 1 lock held by dhcpcd/4887: #0: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x26e/0x1f10 net/ipv4/devinet.c:1101 2 locks held by getty/4979: #0: ffff88823bde28a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock ){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 3 locks held by kworker/0:4/5274: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc900047dfd80 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 1 lock held by syz.0.2602/13285: #0: ffff88804dd5c068 (&uhid->devlock){+.+.}-{3:3}, at: uhid_char_write+0x71/0x10c0 drivers/hid/uhid.c:731 3 locks held by kworker/u8:4/13390: 5 locks held by kworker/u8:13/13456: #0: ffff88801bae3148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc900033f7d80 ( net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffffffff8fa1fbd0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xbb/0xbb0 net/core/net_namespace.c:594 #3: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: cleanup_net+0x503/0xbb0 net/core/net_namespace.c:630 #4: ffffffff8ddc5778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:296 3 locks held by kworker/u8:14/13490: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc900035a7d80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:276 4 locks held by syz-executor/13552: #0: ffff8880353f6420 (sb_writers#9){.+.+}-{0:0}, at: ksys_write+0x12f/0x260 fs/read_write.c:643 #1: ffff8880212ee488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x281/0x500 fs/kernfs/file.c:325 #2: ffff888027f11e18 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2a4/0x500 fs/kernfs/file.c:326 #3: ffffffff8efca8a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 7 locks held by syz-executor/13554: #0: ffff8880353f6420 (sb_writers#9){.+.+}-{0:0}, at: ksys_write+0x12f/0x260 fs/read_write.c:643 #1: ffff888066ed1888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x281/0x500 fs/kernfs/file.c:325 #2: ffff888027f11e18 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2a4/0x500 fs/kernfs/file.c:326 #3: ffffffff8efca8a8 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 #4: ffff88807b73b0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff88807b73b0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff88807b73b0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292 #5: ffff88807b73d250 (&devlink->lock_key#29){+.+.}-{3:3}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x6f/0x6a0 drivers/net/netdevsim/netdev.c:773 1 lock held by syz-executor/13603: #0: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/13614: #0: ffffffff8ddc5778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:328 2 locks held by syz-executor/13659: #0: ffffffff8fa1fbd0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2d6/0x700 net/core/net_namespace.c:504 #1: ffffffff8fa355e8 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x218/0x780 net/ipv4/ip_tunnel.c:1158 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 13456 Comm: kworker/u8:13 Not tainted 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: netns cleanup_net RIP: 0010:serial_out drivers/tty/serial/8250/8250.h:142 [inline] RIP: 0010:serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3322 [inline] RIP: 0010:serial8250_console_write+0xce7/0x1090 drivers/tty/serial/8250/8250_port.c:3393 Code: 44 24 08 48 39 c3 0f 84 b1 01 00 00 45 31 e4 eb 49 e8 fd c1 87 fc 48 83 c3 01 48 8b 3c 24 31 f6 40 0f b6 d5 45 31 ff 41 ff d6 <0f> 1f 00 e8 e1 c1 87 fc 41 83 c4 01 44 89 ef 44 89 e6 e8 52 c3 87 RSP: 0018:ffffc900033f75e8 EFLAGS: 00000002 RAX: 0000000000000031 RBX: ffffffff9a2dbec3 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff8502e725 RDI: ffffffff9a5b2f20 RBP: 0000000000000031 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000010 R14: ffffffff8502e6c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000560709312068 CR3: 000000000db7c000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: console_emit_next_record kernel/printk/printk.c:2983 [inline] console_flush_all+0x53c/0xd70 kernel/printk/printk.c:3049 console_unlock+0xae/0x290 kernel/printk/printk.c:3118 vprintk_emit+0x409/0x600 kernel/printk/printk.c:2348 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2373 br_set_state+0x378/0x880 net/bridge/br_stp.c:57 br_stp_disable_port+0x65/0x1d0 net/bridge/br_stp_if.c:106 del_nbp+0x13c/0xd30 net/bridge/br_if.c:343 br_dev_delete+0x99/0x1a0 net/bridge/br_if.c:386 br_net_exit_batch_rtnl+0x116/0x1f0 net/bridge/br.c:369 cleanup_net+0x548/0xbb0 net/core/net_namespace.c:633 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244