INFO: task syz.0.1663:11656 blocked for more than 143 seconds. Not tainted 6.11.0-rc5-syzkaller-00081-gd5d547aa7b51 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1663 state:D stack:21976 pid:11656 tgid:11656 ppid:11349 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752 eventpoll_release_file+0xcb/0x1c0 fs/eventpoll.c:1106 eventpoll_release include/linux/eventpoll.h:53 [inline] __fput+0x6e0/0x8a0 fs/file_table.c:413 task_work_run+0x251/0x310 kernel/task_work.c:228 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2d52979ef9 RSP: 002b:00007ffd6f9863b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f2d52b17a80 RCX: 00007f2d52979ef9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f2d52b17a80 R08: 0000000000000006 R09: 00007ffd6f9866af R10: 00000000003ffc1c R11: 0000000000000246 R12: 00000000000e2ab8 R13: 00007ffd6f9864c0 R14: 0000000000000032 R15: ffffffffffffffff Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #0: ffffffff8e93d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 1 lock held by khungtaskd/30: #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 3 locks held by kworker/u8:9/1118: #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff8880166e5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90004847d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90004847d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc77f90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 2 locks held by kworker/u8:13/2994: 3 locks held by kworker/u8:14/3033: #0: ffff888015881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015881148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000a367d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000a367d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 2 locks held by getty/4980: #0: ffff88802b2c30a0 (&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+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:0/9161: #0: ffff88802ac2b148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88802ac2b148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc900037efd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc900037efd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4194 3 locks held by kworker/1:6/9636: #0: ffff888015878948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015878948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc900045efd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc900045efd00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 1 lock held by syz.0.1663/11656: #0: ffff88807db50068 (&ep->mtx){+.+.}-{3:3}, at: eventpoll_release_file+0xcb/0x1c0 fs/eventpoll.c:1106 3 locks held by syz.0.1663/11657: 2 locks held by syz.4.1669/11680: 1 lock held by syz-executor/12218: #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 7 locks held by syz-executor/12261: #0: ffff888029488420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2882 [inline] #0: ffff888029488420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x227/0xc90 fs/read_write.c:586 #1: ffff888071a61088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff88801f5561e8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8f521108 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88807b7180e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff88807b7180e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff88807b7180e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1292 #5: ffff88807b71f250 (&devlink->lock_key#94){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 1 lock held by syz-executor/12297: #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/12316: #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 2 locks held by syz-executor/12335: #0: ffffffff8fc77f90 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c6/0x7b0 net/core/net_namespace.c:504 #1: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: wg_netns_pre_exit+0x1f/0x1e0 drivers/net/wireguard/device.c:414 1 lock held by syz.4.1843/12343: #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fc84b48 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x1b0 drivers/net/tun.c:3510 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc5-syzkaller-00081-gd5d547aa7b51 #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+0x241/0x360 lib/dump_stack.c:119 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 9904 Comm: kworker/u8:4 Not tainted 6.11.0-rc5-syzkaller-00081-gd5d547aa7b51 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:227 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4797 [inline] RIP: 0010:__lock_acquire+0x898/0x2040 kernel/locking/lockdep.c:5092 Code: 8b 5d 00 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 40 48 73 93 be 08 00 00 00 e8 80 f6 8a 00 48 0f a3 1d 48 6d 03 12 <73> 1a 48 69 c3 c8 00 00 00 48 8d 98 40 a7 41 93 48 ba 00 00 00 00 RSP: 0018:ffffc9000315f8f0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 00000000000006d3 RCX: ffffffff816fdaf0 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff93734918 RBP: 0000000000000000 R08: ffffffff9373491f R09: 1ffffffff26e6923 R10: dffffc0000000000 R11: fffffbfff26e6924 R12: 0000000000000001 R13: ffff88807e130b28 R14: 0000000000000001 R15: ffff88807e130b28 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020008040 CR3: 000000000e734000 CR4: 0000000000350ef0 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2e/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244