INFO: task syz.2.2809:14897 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2809 state:D stack:27960 pid:14897 tgid:14896 ppid:13303 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x153e/0x4fe0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 super_lock+0x1e0/0x3d0 fs/super.c:116 super_lock_excl fs/super.c:147 [inline] grab_super+0xb9/0x380 fs/super.c:533 sget_fc+0x2c2/0xa40 fs/super.c:804 sget_dev fs/super.c:1408 [inline] get_tree_bdev_flags+0x214/0x4f0 fs/super.c:1680 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3760 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3836 do_mount fs/namespace.c:4159 [inline] __do_sys_mount fs/namespace.c:4348 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4325 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8ca679acb9 RSP: 002b:00007f8ca76fc028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f8ca6a15fa0 RCX: 00007f8ca679acb9 RDX: 0000200000000000 RSI: 0000200000000300 RDI: 0000200000000280 RBP: 00007f8ca6808bf7 R08: 0000200000000380 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8ca6a16038 R14: 00007f8ca6a15fa0 R15: 00007ffe21c16878 INFO: task syz.2.2809:14898 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.2809 state:D stack:28424 pid:14898 tgid:14896 ppid:13303 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x153e/0x4fe0 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 bdev_open+0xe0/0xd30 block/bdev.c:962 bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1076 setup_bdev_super+0x5a/0x5b0 fs/super.c:1612 get_tree_bdev_flags+0x389/0x4f0 fs/super.c:1692 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3760 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3836 do_mount fs/namespace.c:4159 [inline] __do_sys_mount fs/namespace.c:4348 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4325 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8ca679acb9 RSP: 002b:00007f8ca76db028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f8ca6a16090 RCX: 00007f8ca679acb9 RDX: 0000200000000000 RSI: 0000200000000300 RDI: 0000200000000280 RBP: 00007f8ca6808bf7 R08: 0000200000000380 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8ca6a16128 R14: 00007f8ca6a16090 R15: 00007ffe21c16878 Showing all locks held in the system: 2 locks held by ksoftirqd/1/23: 3 locks held by kworker/1:1/29: #0: ffff8880b853abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8524588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8526118 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8526118 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 1 lock held by khungtaskd/31: #0: ffffffff8e75dfa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75dfa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75dfa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/1:2/115: #0: ffff88813ff0e948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254 #1: ffffc9000258fc40 (key_gc_work){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255 #2: ffffffff8e764238 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8e764238 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 2 locks held by getty/5585: #0: ffff88803275d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:6/5909: #0: ffff8880b853abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8524588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 6 locks held by kworker/0:8/6349: #0: ffff8880b843abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8424588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b84271d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b84271d8 (&base->lock){-.-.}-{2:2}, at: add_timer_on+0x18f/0x510 kernel/time/timer.c:1319 #3: ffffffff9a4e3960 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:818 #4: ffff8880b853abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #5: ffff8880b8524588 (psi_seq){-.-.}-{0:0}, at: psi_task_change+0xd4/0x340 kernel/sched/psi.c:919 1 lock held by udevd/7991: #0: ffff888027312358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 1 lock held by udevd/8030: #0: ffff8880271f6358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 5 locks held by kworker/u8:0/13950: #0: ffff8880b843abe0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647 #1: ffff8880b8424588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b8426118 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline] #2: ffff8880b8426118 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085 #3: ffffffff9a428538 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:818 #4: ffffffff8e602ac8 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145 3 locks held by syz.0.2624/14331: 1 lock held by syz.2.2809/14897: #0: ffff8880536dc0e0 (&type->s_umount_key#104/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:345 2 locks held by syz.2.2809/14898: #0: ffff8880298460e0 (&type->s_umount_key#104/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:345 #1: ffff8880271f6358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:962 1 lock held by syz.4.3036/15575: #0: ffffffff8fbd5488 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8fbd5488 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436 2 locks held by syz.6.3308/16447: #0: ffff88807dc369b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x246/0x320 fs/file.c:1255 #1: ffff88804cbc0420 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline] #1: ffff88804cbc0420 (sb_writers#3){.+.+}-{0:0}, at: vfs_writev+0x2aa/0x990 fs/read_write.c:1057 3 locks held by syz-executor/16731: #0: ffff888075e70ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff888075e70ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff888075e700c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346 #2: ffffffff8e764238 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8e764238 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 4 locks held by syz.7.3479/17146: #0: ffff8880644d0ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff8880644d0ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff8880644d00c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346 #2: ffffffff8fd61f08 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff8fd61f08 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644 #3: ffff88806960db38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5b0 net/bluetooth/l2cap_core.c:1763 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xf90/0xfe0 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 14331 Comm: syz.0.2624 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 RIP: 0010:__lock_release kernel/locking/lockdep.c:5564 [inline] RIP: 0010:lock_release+0x167/0x3a0 kernel/locking/lockdep.c:5889 Code: 54 24 14 72 25 89 c1 81 e1 00 00 e0 ff 25 ff ff 1f 00 01 c8 05 00 00 e0 ff 81 c1 00 00 e0 ff 89 45 20 85 c9 0f 85 e6 00 00 00 <45> 89 af 18 0b 00 00 48 8b 45 00 49 89 87 10 0b 00 00 41 39 d5 0f RSP: 0018:ffffc90000a083d0 EFLAGS: 00000083 RAX: 0000000000022007 RBX: 0000000000000202 RCX: 0000000000000102 RDX: 0000000000000002 RSI: ffffffff8e75dfa0 RDI: ffff88802b8e0b70 RBP: ffff88802b8e0b70 R08: ffffc90000a08558 R09: 0000000000000000 R10: ffffc90000a085b8 R11: fffff520001410b9 R12: 0000000000000002 R13: 0000000000000002 R14: ffffffff8e75dfa0 R15: ffff88802b8e0000 FS: 0000000000000000(0000) GS:ffff8881253a3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055c0ed5e0ee8 CR3: 000000000e54a000 CR4: 00000000003526f0 Call Trace: rcu_lock_release include/linux/rcupdate.h:322 [inline] rcu_read_unlock include/linux/rcupdate.h:881 [inline] class_rcu_destructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0x1aaa/0x23c0 arch/x86/kernel/unwind_orc.c:695 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:773 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4411 [inline] slab_alloc_node mm/slub.c:4740 [inline] kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4792 __alloc_skb+0x1d0/0x710 net/core/skbuff.c:696 skb_copy+0x188/0x800 net/core/skbuff.c:2175 mac80211_hwsim_tx_frame_no_nl+0xd00/0x11f0 drivers/net/wireless/virtual/mac80211_hwsim.c:1891 mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2264 mac80211_hwsim_beacon_tx+0x3e8/0x870 drivers/net/wireless/virtual/mac80211_hwsim.c:2365 __iterate_interfaces+0x2ab/0x590 net/mac80211/util.c:760 ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:796 mac80211_hwsim_beacon+0xbb/0x180 drivers/net/wireless/virtual/mac80211_hwsim.c:2395 __run_hrtimer kernel/time/hrtimer.c:1785 [inline] __hrtimer_run_queues+0x527/0xc30 kernel/time/hrtimer.c:1849 hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1866 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:727 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline] RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline] RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x5a/0xb0 kernel/rcu/tree.c:752 Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 8c 0a 82 00 48 c7 c3 58 07 19 93 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 34 8b 03 65 ff 0d 19 e2 6e 11 74 11 83 e0 04 c1 e8 02 5b RSP: 0018:ffffc90003287438 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffff8880b8533758 RCX: 0000000080000001 RDX: 0000000000000000 RSI: ffffffff8c094760 RDI: ffffffff8c094720 RBP: ffffffff81759255 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90003287678 R11: fffff52000650ed1 R12: 0000000000000002 R13: ffffffff8e75dfa0 R14: ffffffff8e09cdd8 R15: dffffc0000000000 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x5f/0x330 kernel/locking/lockdep.c:5831 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:773 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0xbb9/0xd10 mm/page_alloc.c:2972 vfree+0x25a/0x400 mm/vmalloc.c:3479 kcov_put kernel/kcov.c:442 [inline] kcov_close+0x28/0x50 kernel/kcov.c:543 __fput+0x44f/0xa70 fs/file_table.c:468 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x69b/0x2310 kernel/exit.c:971 do_group_exit+0x21b/0x2d0 kernel/exit.c:1112 get_signal+0x1284/0x1330 kernel/signal.c:3034 arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2b7/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb228b5b58e Code: Unable to access opcode bytes at 0x7fb228b5b564. RSP: 002b:00007fb229acef58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007fb229acf6c0 RCX: 00007fb228b5b58e RDX: 00007fb229acefb0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fb228c08bf7 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb228e16218 R14: 00007fb228e16180 R15: 00007ffe8e24f9a8