INFO: task syz.3.779:9885 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.779 state:D stack:27384 pid:9885 tgid:9884 ppid:5628 task_flags:0x400740 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x10e9/0x6820 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7282 schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121 wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:269 coredump_wait fs/coredump.c:537 [inline] vfs_coredump+0x80d/0x5770 fs/coredump.c:1202 get_signal+0x1f2a/0x21e0 kernel/signal.c:3022 arch_do_signal_or_restart+0x91/0x770 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x6f2/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f90b8b9cdd9 RSP: 002b:00007f90b6df60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f90b8e15fa8 RCX: 00007f90b8b9cdd9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f90b8e15fa8 RBP: 00007f90b8e15fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f90b8e16038 R14: 00007ffedc1ff8d0 R15: 00007ffedc1ff9b8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e7e52e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e7e52e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e7e52e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 5 locks held by kworker/u8:5/135: #0: ffff88801c6ae140 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277 #1: ffffc90002e27d08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278 #2: ffffffff905f46a8 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:673 #3: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline] #3: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248 #4: ffffffff8e7f0e28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 3 locks held by kworker/0:2/807: #0: ffff88813fe57140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277 #1: ffffc90004597d08 (rx_mode_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278 #2: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: netdev_rx_mode_work+0x22/0x3e0 net/core/dev_addr_lists.c:1312 1 lock held by dhcpcd/5290: #0: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x1bd/0x1f10 net/ipv4/devinet.c:1120 3 locks held by kworker/0:7/5778: #0: ffff88813fe57140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277 #1: ffffc90004fb7d08 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278 #2: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 1 lock held by syz.3.779/9888: 2 locks held by getty/9955: #0: ffff888038d290a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000a5152e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:0/11568: #0: ffff88813fe94140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277 #1: ffffc90009787d08 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278 #2: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:313 1 lock held by syz-executor/11629: #0: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 3 locks held by kworker/u8:1/11735: #0: ffff8880343f4140 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277 #1: ffffc9000cf27d08 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278 #2: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11f/0x1360 net/ipv6/addrconf.c:4206 2 locks held by syz.6.1098/11810: #0: ffffffff905f46a8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575 #1: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #1: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2102 2 locks held by syz.5.1099/11812: #0: ffffffff905f46a8 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575 #1: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #1: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: register_netdevice_notifier_net+0x23/0xb0 net/core/dev.c:2102 1 lock held by syz.0.1097/11819: #0: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff9060d3e0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3438 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 1667 Comm: kworker/0:1H Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: kblockd blk_mq_run_work_fn RIP: 0010:blk_map_iter_next+0x281/0x1040 block/blk-mq-dma.c:37 Code: 44 89 b4 24 b4 00 00 00 48 89 84 24 a8 00 00 00 48 8d 84 24 a8 00 00 00 48 89 c7 48 89 44 24 48 e8 b4 f7 ff ff 48 8b 54 24 70 <48> 89 c5 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f RSP: 0018:ffffc900062ff498 EFLAGS: 00000206 RAX: 0000000050994000 RBX: 0000000000001000 RCX: ffffffff84d93b3f RDX: ffffc900062ff660 RSI: ffffffff84d938c2 RDI: ffffc900062ff54c RBP: ffff8880563c5600 R08: 0000000000000005 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: 000000000002f400 R13: ffffc900062ff680 R14: 0000000000000000 R15: ffffc900062ff788 FS: 0000000000000000(0000) GS:ffff888124380000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005643ef902950 CR3: 000000000e596000 CR4: 00000000003526f0 Call Trace: __blk_rq_map_sg+0x1ac/0x780 block/blk-mq-dma.c:295 scsi_alloc_sgtables+0x216/0xf10 drivers/scsi/scsi_lib.c:1162 sd_setup_read_write_cmnd drivers/scsi/sd.c:1412 [inline] sd_init_command+0x2ea/0x3b90 drivers/scsi/sd.c:1534 scsi_prepare_cmd drivers/scsi/scsi_lib.c:1730 [inline] scsi_queue_rq+0x11f9/0x3c20 drivers/scsi/scsi_lib.c:1878 blk_mq_dispatch_rq_list+0x422/0x1e70 block/blk-mq.c:2148 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xcea/0x1620 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x1c0 block/blk-mq-sched.c:329 blk_mq_run_work_fn+0x1fe/0x380 block/blk-mq.c:2562 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302 process_scheduled_works kernel/workqueue.c:3385 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245