INFO: task syz.2.4917:20483 blocked for more than 143 seconds. Not tainted 6.11.0-rc2-syzkaller-00004-gb446a2dae984 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.4917 state:D stack:27360 pid:20483 tgid:20482 ppid:19271 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 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] __ww_mutex_lock+0xec2/0x2790 kernel/locking/mutex.c:759 ww_mutex_lock+0x40/0x1f0 kernel/locking/mutex.c:876 drm_modeset_lock+0x6f/0x90 drivers/gpu/drm/drm_modeset_lock.c:398 drm_mode_getplane+0xf0/0x7a0 drivers/gpu/drm/drm_plane.c:840 drm_ioctl_kernel+0x33a/0x440 drivers/gpu/drm/drm_ioctl.c:745 drm_ioctl+0x611/0xad0 drivers/gpu/drm/drm_ioctl.c:842 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f71c8f779f9 RSP: 002b:00007f71c9ce7048 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f71c9105f80 RCX: 00007f71c8f779f9 RDX: 0000000020000180 RSI: 00000000c02064b6 RDI: 0000000000000003 RBP: 00007f71c8fe58ee R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f71c9105f80 R15: 00007fffac777968 Showing all locks held in the system: 2 locks held by kworker/u8:0/11: #0: ffff88801bae6948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801bae6948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90000107d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90000107d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 1 lock held by khungtaskd/30: #0: ffffffff8e7382a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e7382a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e7382a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6620 2 locks held by kswapd0/88: 2 locks held by getty/4972: #0: ffff88802abc00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900031232f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by syz.4.4745/19950: 2 locks held by kworker/u8:10/20236: 1 lock held by syz.2.4917/20483: #0: ffff8880202ec0b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: drm_modeset_lock+0x6f/0x90 drivers/gpu/drm/drm_modeset_lock.c:398 3 locks held by syz.1.5307/21726: #0: ffff88802d904d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] #0: ffff88802d904d80 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2692 #1: ffff88802d904078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x572/0x11a0 net/bluetooth/hci_sync.c:5131 #2: ffffffff8e73d678 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #2: ffffffff8e73d678 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 1 lock held by syz.3.5337/21808: #0: ffff8880202ec0b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: drm_modeset_lock+0x6f/0x90 drivers/gpu/drm/drm_modeset_lock.c:398 1 lock held by syz.3.5337/21813: #0: ffff8880202ec0b0 (crtc_ww_class_mutex){+.+.}-{3:3}, at: drm_modeset_lock+0x6f/0x90 drivers/gpu/drm/drm_modeset_lock.c:398 1 lock held by syz.4.5353/21852: #0: ffffffff8e73d678 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #0: ffffffff8e73d678 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 1 lock held by syz-executor/21863: #0: ffffffff8fa62650 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c6/0x7b0 net/core/net_namespace.c:504 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc2-syzkaller-00004-gb446a2dae984 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 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+0xfee/0x1030 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: 20236 Comm: kworker/u8:10 Not tainted 6.11.0-rc2-syzkaller-00004-gb446a2dae984 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:match_held_lock+0x1/0xb0 kernel/locking/lockdep.c:5204 Code: 75 11 48 89 d8 48 83 c4 10 5b 41 5e 41 5f c3 cc cc cc cc e8 11 f9 ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <53> bd 01 00 00 00 48 39 77 10 74 67 48 89 fb 81 7f 20 00 00 20 00 RSP: 0018:ffffc90003e3f950 EFLAGS: 00000087 RAX: 0000000000000003 RBX: 0000000000000002 RCX: ffffc90003e3f903 RDX: 1ffff920007c7f3c RSI: ffff88814f1d9498 RDI: ffff88802b188b30 RBP: ffffc90003e3fa98 R08: ffffffff8ff6956f R09: 1ffffffff1fed2ad R10: dffffc0000000000 R11: fffffbfff1fed2ae R12: 000000000000000a R13: 0000000000000002 R14: ffff88802b188b30 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555ef307e0 CR3: 000000000e534000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: find_held_lock kernel/locking/lockdep.c:5249 [inline] __lock_release kernel/locking/lockdep.c:5434 [inline] lock_release+0x285/0xa30 kernel/locking/lockdep.c:5780 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:165 [inline] _raw_spin_unlock_bh+0x1b/0x40 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x30f/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x365/0x610 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244