INFO: task syz.0.4174:20206 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.4174      state:D stack:26152 pid:20206 tgid:20205 ppid:16345  task_flags:0x480140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 blk_mq_freeze_queue_wait+0xf4/0x170 block/blk-mq.c:190
 blk_mq_freeze_queue include/linux/blk-mq.h:934 [inline]
 queue_limits_commit_update_frozen+0x5d/0x3e0 block/blk-settings.c:554
 nbd_set_size+0x47e/0x6a0 drivers/block/nbd.c:374
 nbd_genl_size_set+0x2eb/0x3c0 drivers/block/nbd.c:2058
 nbd_genl_reconfigure+0x409/0x1870 drivers/block/nbd.c:2361
 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff66838ebe9
RSP: 002b:00007ff6691d3038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff6685b5fa0 RCX: 00007ff66838ebe9
RDX: 0000000000000840 RSI: 0000200000000180 RDI: 0000000000000004
RBP: 00007ff668411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff6685b6038 R14: 00007ff6685b5fa0 R15: 00007fff57ad5eb8
 </TASK>
INFO: task syz.3.4176:20208 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.4176      state:D stack:26024 pid:20208 tgid:20207 ppid:16092  task_flags:0x400140 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd60ef8ebe9
RSP: 002b:00007fd60fdba038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd60f1b5fa0 RCX: 00007fd60ef8ebe9
RDX: 0000000000000084 RSI: 0000200000000000 RDI: 0000000000000003
RBP: 00007fd60f011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd60f1b6038 R14: 00007fd60f1b5fa0 R15: 00007ffc63b6ca78
 </TASK>
INFO: task syz.5.4179:20223 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.4179      state:D stack:27816 pid:20223 tgid:20221 ppid:10974  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 ____sys_sendmsg+0x505/0x830 net/socket.c:2614
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2703
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f824b38ebe9
RSP: 002b:00007f824c137038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f824b5b6090 RCX: 00007f824b38ebe9
RDX: 000000000000c000 RSI: 0000200000000000 RDI: 0000000000000003
RBP: 00007f824b411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f824b5b6128 R14: 00007f824b5b6090 R15: 00007ffc95801538
 </TASK>
INFO: task syz.1.4180:20230 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.4180      state:D stack:27800 pid:20230 tgid:20229 ppid:15723  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 __sys_sendto+0x3bd/0x520 net/socket.c:2228
 __do_sys_sendto net/socket.c:2235 [inline]
 __se_sys_sendto net/socket.c:2231 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2231
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1c9bb90a7c
RSP: 002b:00007f1c9c939ec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f1c9c939fc0 RCX: 00007f1c9bb90a7c
RDX: 0000000000000020 RSI: 00007f1c9c93a010 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007f1c9c939f14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 00007f1c9c939f68 R14: 00007f1c9c93a010 R15: 0000000000000000
 </TASK>
INFO: task syz.6.4186:20246 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.4186      state:D stack:28664 pid:20246 tgid:20245 ppid:10985  task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82c/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:729
 __sys_sendto+0x3bd/0x520 net/socket.c:2228
 __do_sys_sendto net/socket.c:2235 [inline]
 __se_sys_sendto net/socket.c:2231 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2231
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb87d390a7c
RSP: 002b:00007fb87e2afec0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fb87e2affc0 RCX: 00007fb87d390a7c
RDX: 0000000000000020 RSI: 00007fb87e2b0010 RDI: 0000000000000006
RBP: 0000000000000000 R08: 00007fb87e2aff14 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000006
R13: 00007fb87e2aff68 R14: 00007fb87e2b0010 R15: 0000000000000000
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
 watchdog+0xf93/0xfe0 kernel/hung_task.c:491
 kthread+0x70e/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:trace_hardirqs_on_prepare+0x0/0x30 kernel/trace/trace_preemptirq.c:60
Code: 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d e9 d7 27 b5 09 cc e8 a1 43 b2 09 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 65 8b 05 55 06 da 10 85 c0 74 14 48 8b 3c 24 e8 28 00
RSP: 0018:ffffc90000a07ac8 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 407f50f70379d100
RDX: 0000000000010100 RSI: 0000000000000001 RDI: ffffc90000a07ad8
RBP: 0000000000000000 R08: ffffffff8fa38437 R09: 1ffffffff1f47086
R10: dffffc0000000000 R11: fffffbfff1f47087 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff888125d1b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005558999d1fb0 CR3: 000000000df36000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 irqentry_exit+0x55/0x90 kernel/entry/common.c:187
 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:709
RIP: 0010:console_flush_all+0x7f7/0xc40 kernel/printk/printk.c:3227
Code: 48 21 c3 0f 85 e9 01 00 00 e8 15 49 1f 00 48 8b 5c 24 20 4d 85 f6 75 07 e8 06 49 1f 00 eb 06 e8 ff 48 1f 00 fb 48 8b 44 24 28 <42> 80 3c 20 00 74 08 48 89 df e8 3a b2 82 00 48 8b 1b 48 8b 44 24
RSP: 0018:ffffc90000a07b80 EFLAGS: 00000246
RAX: 1ffffffff1d367d7 RBX: ffffffff8e9b3eb8 RCX: ffff88801d29da00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000a07cd0 R08: ffffffff8fa38437 R09: 1ffffffff1f47086
R10: dffffc0000000000 R11: fffffbfff1f47087 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000200 R15: ffffffff8e9b3e60
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
 _printk+0xcf/0x120 kernel/printk/printk.c:2475
 ip6_tnl_xmit_ctl+0x587/0x660 net/ipv6/ip6_tunnel.c:-1
 ip6_tnl_xmit+0xaff/0x2b10 net/ipv6/ip6_tunnel.c:1157
 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1401 [inline]
 ip6_tnl_start_xmit+0xc1d/0x1150 net/ipv6/ip6_tunnel.c:1449
 __netdev_start_xmit include/linux/netdevice.h:5222 [inline]
 netdev_start_xmit include/linux/netdevice.h:5231 [inline]
 xmit_one net/core/dev.c:3839 [inline]
 dev_hard_start_xmit+0x2d7/0x830 net/core/dev.c:3855
 __dev_queue_xmit+0x1b8d/0x3b50 net/core/dev.c:4725
 neigh_output include/net/neighbour.h:547 [inline]
 ip6_finish_output2+0x11fb/0x16a0 net/ipv6/ip6_output.c:141
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ndisc_send_skb+0xb54/0x1440 net/ipv6/ndisc.c:512
 addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4037
 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1798 [inline]
 __run_timers kernel/time/timer.c:2372 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 handle_softirqs+0x283/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 53 e7 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d f3 96 0e 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2
RAX: 407f50f70379d100 RBX: ffffffff819683b8 RCX: 407f50f70379d100
RDX: 0000000000000001 RSI: ffffffff8be33660 RDI: ffffffff819683b8
RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3
R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fa38430
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff11003a53b40
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315
 common_startup_64+0x13e/0x147
 </TASK>