INFO: task syz.1.2087:11142 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.2087 state:D stack:24888 pid:11142 tgid:11142 ppid:5810 task_flags:0x400040 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5260 [inline]
__schedule+0x147b/0x4f50 kernel/sched/core.c:6867
__schedule_loop kernel/sched/core.c:6949 [inline]
schedule+0x164/0x360 kernel/sched/core.c:6964
request_wait_answer fs/fuse/dev.c:585 [inline]
__fuse_request_send fs/fuse/dev.c:599 [inline]
__fuse_simple_request+0x121f/0x1c60 fs/fuse/dev.c:693
fuse_simple_request fs/fuse/fuse_i.h:1263 [inline]
fuse_flush+0x673/0x8b0 fs/fuse/file.c:494
filp_flush+0xc0/0x190 fs/open.c:1533
filp_close+0x1d/0x40 fs/open.c:1546
__range_close fs/file.c:790 [inline]
__do_sys_close_range fs/file.c:849 [inline]
__se_sys_close_range+0x375/0x670 fs/file.c:813
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: 0033:0x7f988039acb9
RSP: 002b:00007ffcef173858 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007f9880617da0 RCX: 00007f988039acb9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f9880617da0 R08: 00007f9880616038 R09: 0000000000000000
R10: 00000000005f32cc R11: 0000000000000246 R12: 0000000000051931
R13: 00007f988061609c R14: 00000000000516b0 R15: 00007f9880616090
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d9c7780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
7 locks held by kworker/u8:6/1116:
#0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88801aa94938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3340
#1: ffffc9000497fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000497fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3340
#2: ffffffff8ed2ab60 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xfe/0x7b0 net/core/net_namespace.c:670
#3: ffff88805cac70d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
#3: ffff88805cac70d8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
#3: ffff88805cac70d8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x117/0x3f0 net/devlink/core.c:506
#4: ffff88803712c300 (&devlink->lock_key#2){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
#4: ffff88803712c300 (&devlink->lock_key#2){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
#4: ffff88803712c300 (&devlink->lock_key#2){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x3f0 net/devlink/core.c:506
#5: ffffffff8ed394f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xed/0x680 drivers/net/netdevsim/netdev.c:1175
#6: ffff888036768e98 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: netdev_lock include/linux/netdevice.h:2781 [inline]
#6: ffff888036768e98 (&dev_instance_lock_key#24){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0x583/0x2360 net/core/dev.c:12356
2 locks held by getty/5562:
#0: ffff88803526d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/13624:
#0: ffffffff8f27d248 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f27d248 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8f27d248 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8ed394f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8ed394f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8ed394f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071
2 locks held by syz.2.3092/13665:
#0: ffffffff8ed2ab60 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cb/0x570 net/core/net_namespace.c:577
#1: ffffffff8ed394f8 (rtnl_mutex){+.+.}-{4:4}, at: ipmr_net_exit_batch+0x20/0x90 net/ipv4/ipmr.c:3276
2 locks held by syz.5.3105/13706:
#0: ffffffff8ed2ab60 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x3cb/0x570 net/core/net_namespace.c:577
#1: ffffffff8ed394f8 (rtnl_mutex){+.+.}-{4:4}, at: register_nexthop_notifier+0x88/0x290 net/ipv4/nexthop.c:3971
6 locks held by syz.4.3108/13714:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
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+0x726/0x8b0 kernel/kthread.c:463
ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 13714 Comm: syz.4.3108 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026
RIP: 0010:_raw_spin_lock_irqsave+0x4/0x60 kernel/locking/spinlock.c:161
Code: 72 67 aa f6 48 83 c4 08 48 89 df 5b e9 35 1f ab f6 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa <41> 56 53 49 89 fe 9c 5b fa f7 c3 00 02 00 00 74 05 e8 d6 ca d5 f6
RSP: 0018:ffffc9000559f518 EFLAGS: 00000246
RAX: 1ffff92000ab3eb1 RBX: ffffc9000559f580 RCX: 0000000000000046
RDX: 0000000000000003 RSI: ffffffff8d396bc6 RDI: ffff8880b8946400
RBP: ffffc9000559f618 R08: ffffffff8af23b60 R09: ffffffff8d9c7780
R10: 0000000000000000 R11: fffffbfff1e4f72f R12: dffffc0000000000
R13: 1ffff92000ab3eac R14: ffff88805e31d800 R15: ffff8880b8946400
FS: 00007f92b48466c0(0000) GS:ffff8881268fa000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feb918f8400 CR3: 0000000037884000 CR4: 00000000003526f0
Call Trace:
rt_mutex_slowunlock+0xbf/0x8b0 kernel/locking/rtmutex.c:1417
spin_unlock include/linux/spinlock_rt.h:105 [inline]
__kmem_cache_alloc_bulk+0x195/0x560 mm/slub.c:7429
kmem_cache_alloc_bulk_noprof+0xeb/0x700 mm/slub.c:7501
xdp_recv_frames net/bpf/test_run.c:249 [inline]
xdp_test_run_batch net/bpf/test_run.c:350 [inline]
bpf_test_run_xdp_live+0x179c/0x1cf0 net/bpf/test_run.c:379
bpf_prog_test_run_xdp+0x81c/0x1160 net/bpf/test_run.c:1396
bpf_prog_test_run+0x2cd/0x340 kernel/bpf/syscall.c:4703
__sys_bpf+0x5cb/0x920 kernel/bpf/syscall.c:6182
__do_sys_bpf kernel/bpf/syscall.c:6274 [inline]
__se_sys_bpf kernel/bpf/syscall.c:6272 [inline]
__x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6272
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: 0033:0x7f92b65eacb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f92b4846028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f92b6865fa0 RCX: 00007f92b65eacb9
RDX: 0000000000000050 RSI: 0000200000000600 RDI: 000000000000000a
RBP: 00007f92b6658bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f92b6866038 R14: 00007f92b6865fa0 R15: 00007ffd785590f8