INFO: task syz.0.8061:2627 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.8061      state:D stack:27448 pid:2627  tgid:2623  ppid:28322  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5504 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7228
 __schedule_loop kernel/sched/core.c:7307 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7322
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7379
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 nfsd_nl_version_set_doit+0xcd/0x7a0 fs/nfsd/nfsctl.c:1798
 genl_family_rcv_msg_doit+0x233/0x340 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x614/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x9b9/0xa20 net/socket.c:2684
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7feada19ce59
RSP: 002b:00007feadb143028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007feada415fa0 RCX: 00007feada19ce59
RDX: 0000000004008090 RSI: 0000200000000140 RDI: 0000000000000007
RBP: 00007feada232e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feada416038 R14: 00007feada415fa0 R15: 00007ffc273c9c38
 </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 05/09/2026
Call Trace:
 <TASK>
 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:162 [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:353 [inline]
 watchdog+0xfd7/0x1030 kernel/hung_task.c:561
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5833 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:deref_stack_reg+0x18e/0x220 arch/x86/kernel/unwind_orc.c:422
Code: 20 c2 20 ca 80 fa 01 75 46 49 8d 40 08 4c 39 e0 0f 97 c1 4c 39 f0 0f 96 c0 20 c8 3c 01 75 30 4c 89 c7 49 89 f7 e8 12 07 00 00 <49> 89 c6 48 8b 5c 24 08 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08
RSP: 0018:ffffc90004d27498 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff920009a4eb1 RCX: 0000000000000001
RDX: ffffc90004d275c8 RSI: dffffc0000000000 RDI: ffffc90004d27918
RBP: ffffc90004d20000 R08: ffffc90004d27918 R09: 0000000000000000
R10: ffffc90004d275d8 R11: fffff520009a4ebd R12: 1ffff920009a4eb2
R13: 1ffff920009a4eb3 R14: ffffc90004d28000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88812537b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd0ec85ff8 CR3: 000000007e8e0000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 unwind_next_frame+0x19bd/0x2550 arch/x86/kernel/unwind_orc.c:-1
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2700 [inline]
 slab_free mm/slub.c:6310 [inline]
 kfree+0x1c5/0x640 mm/slub.c:6625
 skb_kfree_head net/core/skbuff.c:1077 [inline]
 skb_free_head net/core/skbuff.c:1089 [inline]
 skb_release_data+0x85e/0xab0 net/core/skbuff.c:1116
 skb_release_all net/core/skbuff.c:1191 [inline]
 __kfree_skb+0x5d/0x210 net/core/skbuff.c:1205
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:892 [inline]
 nsim_dev_trap_report_work+0x7ac/0xb40 drivers/net/netdevsim/dev.c:922
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>