INFO: task syz.2.1615:11622 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.2.1615 state:D stack:28264 pid:11622 tgid:11621 ppid:5623 task_flags:0x480040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5510 [inline] __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7326 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821 relay_open+0x3a4/0x900 kernel/relay.c:515 blk_trace_setup_prepare+0x425/0x5a0 kernel/trace/blktrace.c:715 blk_trace_setup+0x2f5/0x520 kernel/trace/blktrace.c:789 blk_trace_ioctl+0x37f/0x910 kernel/trace/blktrace.c:937 blkdev_ioctl+0x4c1/0x740 block/ioctl.c:786 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5b17d9e0d9 RSP: 002b:00007f5b15ff6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f5b18025fa0 RCX: 00007f5b17d9e0d9 RDX: 0000200000000000 RSI: 00000000c0481273 RDI: 0000000000000004 RBP: 00007f5b17e35024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5b18026038 R14: 00007f5b18025fa0 R15: 00007f5b1814fa48 Showing all locks held in the system: 3 locks held by init/1: 3 locks held by kworker/0:0/9: #0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc900000e7c40 (netdev_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc900000e7c40 (netdev_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff90027d40 (rtnl_mutex){+.+.}-{4:4}, at: netdev_work_proc+0x6f/0x770 net/core/netdev_work.c:132 3 locks held by kworker/u8:0/12: #0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90000117c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90000117c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff90027d40 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 1 lock held by khungtaskd/30: #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 4 locks held by kworker/u9:0/50: #0: ffff888075a22140 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888075a22140 ((wq_completion)hci6){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90000ba7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90000ba7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffff8881a052cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1cb/0x3f0 net/bluetooth/hci_sync.c:331 #3: ffff8881a052c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0xa6f/0x1190 net/bluetooth/hci_sync.c:5894 3 locks held by kworker/u8:4/57: #0: ffff888032055940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff888032055940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc900015e7c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc900015e7c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff90027d40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff90027d40 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4769 3 locks held by kworker/1:2/985: #0: ffff88801b029d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801b029d40 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90004effc40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90004effc40 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff90027d40 (rtnl_mutex){+.+.}-{4:4}, at: reg_check_chans_work+0xac/0x1110 net/wireless/reg.c:2469 6 locks held by kworker/u8:7/1112: 3 locks held by udevd/4978: 3 locks held by dhcpcd/5273: 3 locks held by dhcpcd/5274: 3 locks held by dhcpcd/5275: 2 locks held by getty/5366: #0: ffff8880325500a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 2 locks held by sshd-session/5595: 3 locks held by syz-executor/5602: 3 locks held by syz-executor/5604: #0: ffff888032be14a8 (&tsk->futex.exit_mutex){+.+.}-{4:4}, at: futex_cleanup_begin kernel/futex/core.c:1509 [inline] #0: ffff888032be14a8 (&tsk->futex.exit_mutex){+.+.}-{4:4}, at: futex_exit_release+0x33/0x1d0 kernel/futex/core.c:1562 #1: ffff888035874378 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:611 [inline] #1: ffff888035874378 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/mmap_lock.c:441 [inline] #1: ffff888035874378 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x36/0x340 mm/mmap_lock.c:501 #2: ffffffff8ec848e0 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4402 [inline] #2: ffffffff8ec848e0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim+0xbd/0x310 mm/page_alloc.c:4427 3 locks held by syz-executor/5614: 3 locks held by syz-executor/5622: 3 locks held by kworker/0:6/5696: #0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #0: ffff88801b02b140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #1: ffffc90004fefc40 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3297 [inline] #1: ffffc90004fefc40 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0xa20/0x14e0 kernel/workqueue.c:3405 #2: ffffffff90027d40 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by dhcpcd/8725: 3 locks held by dhcpcd/8726: 3 locks held by dhcpcd/8742: 2 locks held by dhcpcd/8745: 3 locks held by dhcpcd/8830: 3 locks held by dhcpcd/8832: 1 lock held by dhcpcd/8846: 3 locks held by dhcpcd/8849: 2 locks held by syz.5.956/9301: 5 locks held by kworker/u8:20/9653: 3 locks held by kworker/u8:23/9657: 3 locks held by syz.4.1482/11114: 5 locks held by syz-executor/11331: 3 locks held by syz-executor/11336: 2 locks held by syz.2.1615/11622: #0: ffff888026669b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:794 [inline] #0: ffff888026669b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:808 [inline] #0: ffff888026669b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d0/0x520 kernel/trace/blktrace.c:788 #1: ffffffff8ebb96c0 (relay_channels_mutex){+.+.}-{4:4}, at: relay_open+0x3a4/0x900 kernel/relay.c:515 3 locks held by syz-executor/11806: 1 lock held by syz-executor/11811: 2 locks held by fido_id/11960: 2 locks held by syz.3.1707/11974: 3 locks held by syz.3.1707/11982: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65 trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 5622 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:preempt_count_add+0x42/0x190 kernel/sched/core.c:5985 Code: 78 9a 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 ea 00 00 00 83 3d be 96 e3 18 00 75 07 65 8b 05 65 41 d8 11 65 01 3d 5e 41 d8 11 <48> c7 c0 80 05 78 9a 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 e5 00 RSP: 0000:ffffc900046fed28 EFLAGS: 00000006 RAX: 0000000000000002 RBX: 0000000000000899 RCX: ffffffff9a780503 RDX: 0000000000000129 RSI: ffffffff8c4bbe60 RDI: 0000000000000001 RBP: 0000000000000001 R08: ffff888140ee8237 R09: 1ffff110281dd046 R10: dffffc0000000000 R11: ffffffff8bcf4760 R12: 1ffffffff355ace6 R13: 00000000ffffffff R14: 0000012949634114 R15: dffffc0000000000 FS: 000055558d26c500(0000) GS:ffff888125055000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000560b57ca8756 CR3: 000000005c134000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: delay_tsc+0x65/0xc0 arch/x86/lib/delay.c:79 udelay include/asm-generic/delay.h:62 [inline] wait_for_lsr+0x147/0x2f0 drivers/tty/serial/8250/8250_port.c:1988 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3235 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3300 [inline] serial8250_console_write+0x12ef/0x1ba0 drivers/tty/serial/8250/8250_port.c:3385 console_emit_next_record kernel/printk/printk.c:3183 [inline] console_flush_one_record kernel/printk/printk.c:3269 [inline] console_flush_all+0x6ea/0xaf0 kernel/printk/printk.c:3343 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413 vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479 _printk+0xdd/0x130 kernel/printk/printk.c:2504 dump_unreclaimable_slab+0x112/0x150 mm/slab_common.c:1184 dump_header+0x3f5/0x4b0 mm/oom_kill.c:470 oom_kill_process+0x3ab/0x970 mm/oom_kill.c:1031 out_of_memory+0x1191/0x1480 mm/oom_kill.c:1151 __alloc_pages_may_oom+0x1ea/0x330 mm/page_alloc.c:4116 __alloc_pages_slowpath+0x6e8/0xcc0 mm/page_alloc.c:4967 __alloc_frozen_pages_noprof+0x31f/0x380 mm/page_alloc.c:5317 alloc_pages_mpol+0x212/0x380 mm/mempolicy.c:2490 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline] alloc_pages_noprof+0xac/0x2a0 mm/mempolicy.c:2581 folio_alloc_noprof+0x1e/0x30 mm/mempolicy.c:2591 filemap_alloc_folio_noprof+0x111/0x470 mm/filemap.c:1019 __filemap_get_folio_mpol+0x402/0x1000 mm/filemap.c:2018 __filemap_get_folio include/linux/pagemap.h:761 [inline] filemap_fault+0xa84/0x13b0 mm/filemap.c:3598 __do_fault+0x138/0x2a0 mm/memory.c:5425 do_read_fault mm/memory.c:5860 [inline] do_fault mm/memory.c:5994 [inline] do_pte_missing+0x2215/0x34b0 mm/memory.c:4566 handle_pte_fault mm/memory.c:6379 [inline] __handle_mm_fault mm/memory.c:6517 [inline] handle_mm_fault+0x1b36/0x3080 mm/memory.c:6686 do_user_addr_fault+0xa4d/0x1340 arch/x86/mm/fault.c:1343 handle_page_fault arch/x86/mm/fault.c:1483 [inline] exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595 RIP: 0033:0x7f1ed515923e Code: Unable to access opcode bytes at 0x7f1ed5159214. RSP: 002b:00007f1ed554fd30 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 000055558d26c500 RCX: 00007f1ed515e90e RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f1ed554fdec R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388 R13: 00000000000927c0 R14: 000000000006b07c R15: 00007f1ed554fe40