INFO: task syz.6.2027:14145 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.2027 state:D stack:23216 pid:14145 ppid: 12908 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127 _free_event+0x34/0xe60 kernel/events/core.c:5133 put_event kernel/events/core.c:5258 [inline] perf_event_release_kernel+0x83e/0x8d0 kernel/events/core.c:5383 perf_release+0x37/0x40 kernel/events/core.c:5393 __fput+0x234/0x930 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x626/0x20c0 kernel/exit.c:883 do_group_exit+0x12e/0x300 kernel/exit.c:997 get_signal+0x6ca/0x12c0 kernel/signal.c:2900 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f9a40b62dd9 RSP: 002b:00007f9a3edbbfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: fffffffffffffff2 RBX: 00007f9a40ddbfa0 RCX: 00007f9a40b62dd9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000022023400 RBP: 00007f9a40bf8d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f9a40ddc038 R14: 00007f9a40ddbfa0 R15: 00007ffe09545418 Showing all locks held in the system: 3 locks held by kworker/u4:0/9: 1 lock held by khungtaskd/27: #0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by dhcpcd/3854: #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x258/0x1a70 net/ipv4/devinet.c:1076 2 locks held by getty/3946: #0: ffff88802c88e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158 3 locks held by kworker/u4:7/5681: #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc900032efd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 6 locks held by kworker/u4:8/10173: #0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc90003acfd00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8d4314d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589 #3: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:11646 [inline] #3: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x165/0x3c0 net/core/dev.c:11684 #4: ffff88805bb94d00 (team->team_lock_key#12){+.+.}-{3:3}, at: team_del_slave+0x2e/0x1e0 drivers/net/team/team.c:2011 #5: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #5: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845 3 locks held by kworker/1:39/14757: #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1 #1: ffffc90003cefd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285 #2: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 4 locks held by syz.2.2730/17785: 2 locks held by syz.9.2749/17861: #0: ffffffff8d4314d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:499 #1: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1279 1 lock held by syz.3.2773/17965: 1 lock held by syz-executor/17969: #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ee/0xf30 net/core/rtnetlink.c:5684 1 lock held by syz-executor/18023: #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: __rtnl_newlink net/core/rtnetlink.c:3479 [inline] #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_newlink+0xa8f/0x1a50 net/core/rtnetlink.c:3577 1 lock held by syz.5.2790/18048: 1 lock held by syz.7.2798/18099: #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3fc/0x1ec0 drivers/net/tun.c:3052 1 lock held by syz.7.2798/18100: #0: ffffffff8d43d3c8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3fc/0x1ec0 drivers/net/tun.c:3052 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3550 Comm: klogd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:unwind_next_frame+0x9f7/0x1d90 arch/x86/kernel/unwind_orc.c:545 Code: 00 fc ff df 48 8b 44 24 20 42 80 3c 28 00 4c 8b 74 24 18 74 08 4c 89 f7 e8 76 2d 89 00 4d 89 3e 48 8b 44 24 40 42 80 3c 28 00 <4c> 8b 74 24 38 4c 8b 7c 24 70 74 08 4c 89 f7 e8 55 2d 89 00 48 8b RSP: 0018:ffffc90002e3f3c8 EFLAGS: 00000246 RAX: 1ffff920005c7e98 RBX: ffffc90002e3f488 RCX: 1ffff920005c7e01 RDX: 1ffffffff1cf1264 RSI: ffffffff8e789322 RDI: ffffc90002e3f998 RBP: ffffc90002e3f4d0 R08: 0000000000000001 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520005c7e9d R12: 1ffffffff1cf1264 R13: dffffc0000000000 R14: ffffc90002e3f4d0 R15: ffffffff87dbe1ff FS: 00007f952e73cc80(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f762d0d6e80 CR3: 000000007de26000 CR4: 00000000003506e0 DR0: 0000200000000300 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa6/0xf0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] kmem_cache_alloc_node+0x12d/0x2d0 mm/slub.c:3261 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] alloc_skb_with_frags+0xa7/0x730 net/core/skbuff.c:6170 sock_alloc_send_pskb+0x87f/0x9a0 net/core/sock.c:2536 unix_dgram_sendmsg+0x5fc/0x18a0 net/unix/af_unix.c:1809 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2072 __do_sys_sendto net/socket.c:2084 [inline] __se_sys_sendto net/socket.c:2080 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2080 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f952e88c407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007ffcbdd79420 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f952e73cc80 RCX: 00007f952e88c407 RDX: 000000000000004d RSI: 00007ffcbdd79560 RDI: 0000000000000003 RBP: 00007ffcbdd79990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000202 R12: 00007ffcbdd799a8 R13: 00007ffcbdd79560 R14: 0000000000000032 R15: 00007ffcbdd79560