INFO: task syz.0.2403:14672 blocked for more than 143 seconds. Not tainted 6.14.0-rc3-syzkaller-00137-g27eddbf34490 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2403 state:D stack:25664 pid:14672 tgid:14668 ppid:5835 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x18bc/0x4c40 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 sync_bdevs+0x1ae/0x340 block/bdev.c:1246 ksys_sync+0xe2/0x1c0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:113 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: 0033:0x7f85e5f8d0a9 RSP: 002b:00007f85e6dc8038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f85e61a5fa0 RCX: 00007f85e5f8d0a9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f85e61a5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f85e61a5fa0 R15: 00007ffcb053e0e8 Showing all locks held in the system: 1 lock held by rcu_exp_gp_kthr/19: #0: ffff8880b863e7d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:606 1 lock held by khungtaskd/30: #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 1 lock held by syslogd/5181: #0: ffff8880b863e7d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:606 2 locks held by getty/5580: #0: ffff88814d33b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 1 lock held by udevd/5829: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 3 locks held by kworker/u8:11/6048: #0: ffff8880b863e7d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb0/0x140 kernel/sched/core.c:606 #1: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #1: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2370 [inline] #1: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run4+0x244/0x590 kernel/trace/bpf_trace.c:2414 #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] #2: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: batadv_nc_worker+0xcb/0x610 net/batman-adv/network-coding.c:719 1 lock held by syz.0.2403/14672: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15382: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15386: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15387: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15388: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15389: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15390: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15391: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 1 lock held by syz.2.2585/15394: #0: ffff888025d4f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x1ae/0x340 block/bdev.c:1246 3 locks held by kworker/u8:10/15494: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc90003827c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003827c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285 2 locks held by syz.5.2752/15965: #0: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517 #1: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:302 [inline] #1: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x820 kernel/rcu/tree_exp.h:996 2 locks held by syz.9.2757/15980: #0: ffffffff903c2868 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff903c2868 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff903c2868 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:564 #1: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline] #1: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021 1 lock held by syz.8.2756/15981: #0: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fec2ac8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6918 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc3-syzkaller-00137-g27eddbf34490 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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: 12 Comm: kworker/u8:1 Not tainted 6.14.0-rc3-syzkaller-00137-g27eddbf34490 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_wait_context kernel/locking/lockdep.c:4852 [inline] RIP: 0010:__lock_acquire+0x57d/0x2100 kernel/locking/lockdep.c:5178 Code: 8c e8 07 c2 e4 ff 48 ba 00 00 00 00 00 fc ff df 90 0f 0b 90 90 90 31 db 48 81 c3 c4 00 00 00 48 89 d8 48 c1 e8 03 0f b6 04 10 <84> c0 0f 85 f8 12 00 00 0f b6 2b 41 0f b6 04 16 84 c0 0f 85 0c 13 RSP: 0018:ffffc90000a18a30 EFLAGS: 00000807 RAX: 0000000000000000 RBX: ffffffff93ead854 RCX: ffffffff819cb7fc RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff94511898 RBP: 00000000000c42e2 R08: ffffffff9451189f R09: 1ffffffff28a2313 R10: dffffc0000000000 R11: fffffbfff28a2314 R12: ffff88801c6864d4 R13: 0000000000000019 R14: 1ffff110038d0cbb R15: ffff88801c6865d8 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fca04f79178 CR3: 00000000789b6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] drm_handle_vblank+0xdc/0x510 drivers/gpu/drm/drm_vblank.c:1935 vkms_vblank_simulate+0xd6/0x360 drivers/gpu/drm/vkms/vkms_crtc.c:29 __run_hrtimer kernel/time/hrtimer.c:1801 [inline] __hrtimer_run_queues+0x59b/0xd30 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5855 Code: 2b 00 74 08 4c 89 f7 e8 4a c1 89 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900001178a0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000022f20 RCX: ffff88801c6864e8 RDX: dffffc0000000000 RSI: ffffffff8c2ab6a0 RDI: ffffffff8c8019c0 RBP: ffffc900001179f0 R08: ffffffff9451192f R09: 1ffffffff28a2325 R10: dffffc0000000000 R11: fffffbfff28a2326 R12: 1ffff92000022f1c R13: dffffc0000000000 R14: ffffc90000117900 R15: 0000000000000246 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] batadv_nc_purge_paths+0xe8/0x3b0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x365/0x610 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244