INFO: task syz.3.817:8984 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.817 state:D stack:26048 pid:8984 tgid:8984 ppid:5831 task_flags:0x400040 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6857 request_wait_answer+0x4f8/0x900 fs/fuse/dev.c:453 __fuse_request_send fs/fuse/dev.c:467 [inline] __fuse_simple_request+0x32d/0xcb0 fs/fuse/dev.c:561 fuse_simple_request fs/fuse/fuse_i.h:1197 [inline] fuse_flush+0x500/0x6e0 fs/fuse/file.c:557 filp_flush+0x107/0x1b0 fs/open.c:1540 filp_close+0x1c/0x30 fs/open.c:1553 __range_close fs/file.c:746 [inline] __do_sys_close_range+0x380/0x700 fs/file.c:805 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7efe0a18d169 RSP: 002b:00007ffef5b52d48 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 0000000000039925 RCX: 00007efe0a18d169 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007efe0a3a7ba0 R08: 0000000000000001 R09: 0000000df5b5303f R10: 00007efe0a000000 R11: 0000000000000246 R12: 00007efe0a3a5fac R13: 00007efe0a3a5fa0 R14: ffffffffffffffff R15: 00007ffef5b52e60 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff88814d3b4948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213 #1: ffffc90000117d18 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214 #2: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x121/0x14e0 net/ipv6/addrconf.c:4190 1 lock held by khungtaskd/31: #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bd140 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 4 locks held by klogd/5184: #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline] #0: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591 #1: ffff8880b8628a88 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: fs_reclaim_acquire mm/page_alloc.c:3870 [inline] #1: ffff8880b8628a88 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: fs_reclaim_acquire+0xae/0x150 mm/page_alloc.c:3861 #2: ffffffff9aacc058 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x13b/0x370 lib/debugobjects.c:873 #3: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:606 [inline] #3: ffff8880b863ec18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:591 1 lock held by dhcpcd/5489: #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x26e/0x1f50 net/ipv4/devinet.c:1129 2 locks held by getty/5582: #0: ffff88814d6e50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 5 locks held by kworker/1:7/5870: #0: ffff8880232c7948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3213 #1: ffffc90004cc7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3214 #2: ffff88814572c190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #2: ffff88814572c190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c1/0x4e10 drivers/usb/core/hub.c:5861 #3: ffff888028c6e510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline] #3: ffff888028c6e510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5430 [inline] #3: ffff888028c6e510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] #3: ffff888028c6e510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5833 [inline] #3: ffff888028c6e510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x27ec/0x4e10 drivers/usb/core/hub.c:5915 #4: ffff888028453168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5431 [inline] #4: ffff888028453168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] #4: ffff888028453168 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5833 [inline] #4: ffff888028453168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2815/0x4e10 drivers/usb/core/hub.c:5915 5 locks held by kworker/u8:11/6079: 2 locks held by syz.4.1291/11761: #0: ffffffff8fee2890 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:512 #1: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: fib_net_exit_batch+0x15/0xa0 net/ipv4/fib_frontend.c:1646 2 locks held by syz.9.1296/11801: #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3517 #1: ffffffff8e1c85b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:302 1 lock held by syz.0.1251/11820: #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6918 1 lock held by syz.5.1299/11823: #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x1a1/0x10c0 net/core/dev_ioctl.c:852 1 lock held by syz.5.1299/11825: #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #0: ffffffff8fef85a8 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x1a1/0x10c0 net/core/dev_ioctl.c:852 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 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+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5807 Comm: syz-executor Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:debug_smp_processor_id+0x0/0x20 lib/smp_processor_id.c:59 Code: e8 75 a7 41 f6 e8 c0 74 f4 ff 90 65 ff 0d 80 3c ac 74 e9 40 ff ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 c7 c6 a0 69 d3 8b 48 c7 c7 e0 69 d3 8b e9 f9 fe ff RSP: 0018:ffffc90003ccff00 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000002 RCX: ffffffff81c1a5c5 RDX: 0000000000000000 RSI: ffffffff8bd369a0 RDI: ffffffff8dab5ce0 RBP: ffffc90003ccff58 R08: 0000000000000000 R09: fffffbfff20c4d82 R10: ffffffff90626c17 R11: 0000000000000000 R12: ffff88802a35a440 R13: 00000000000000e6 R14: 0000000000000000 R15: 0000000000000000 FS: 000055556ec7f500(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000790a2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tick_nohz_user_enter_prepare include/linux/tick.h:317 [inline] exit_to_user_mode_loop kernel/entry/common.c:127 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x118/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0d24dbf9e3 Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 5e db 1b 00 00 74 14 b8 e6 00 00 00 0f 05 d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10 RSP: 002b:00007ffefb02d6d8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f0d24dbf9e3 RDX: 00007ffefb02d6f0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 000000000001276c R09: 00007f0d25b86000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffefb02db40 R13: 0000000000000004 R14: 00007ffefb02d72c R15: 00007ffefb02d7c0