INFO: task syz.3.1551:11837 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1551      state:D stack:26328 pid:11837 tgid:11836 ppid:5822   task_flags:0x480140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 blk_mq_freeze_queue_wait+0x101/0x180 block/blk-mq.c:191
 blk_mq_freeze_queue include/linux/blk-mq.h:956 [inline]
 queue_limits_commit_update_frozen+0x55/0xd0 block/blk-settings.c:590
 nbd_set_size+0x454/0x680 drivers/block/nbd.c:374
 nbd_genl_size_set drivers/block/nbd.c:2069 [inline]
 nbd_genl_reconfigure+0x7f5/0x1ea0 drivers/block/nbd.c:2373
 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
 __sys_sendmsg net/socket.c:2784 [inline]
 __do_sys_sendmsg net/socket.c:2789 [inline]
 __se_sys_sendmsg net/socket.c:2787 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f16ea99c819
RSP: 002b:00007f16eb807028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f16eac15fa0 RCX: 00007f16ea99c819
RDX: 0000000020040080 RSI: 00002000000003c0 RDI: 0000000000000004
RBP: 00007f16eaa32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f16eac16038 R14: 00007f16eac15fa0 R15: 00007ffe6ffb7518
 </TASK>
INFO: task syz.1.1553:11842 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1553      state:D stack:27936 pid:11842 tgid:11841 ppid:5825   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x672/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f108cd5d04e
RSP: 002b:00007f108dba1e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f108dba36c0 RCX: 00007f108cd5d04e
RDX: 0000000000000020 RSI: 00007f108dba2000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007f108dba1f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f108dba1f58 R14: 00007f108dba2000 R15: 0000000000000000
 </TASK>
INFO: task syz.2.1554:11845 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1554      state:D stack:28224 pid:11845 tgid:11844 ppid:5824   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x672/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f02abd5d04e
RSP: 002b:00007f02a9ff4e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f02a9ff66c0 RCX: 00007f02abd5d04e
RDX: 0000000000000020 RSI: 00007f02a9ff5000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007f02a9ff4f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00007f02a9ff4f58 R14: 00007f02a9ff5000 R15: 0000000000000000
 </TASK>
INFO: task syz.2.1554:11846 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1554      state:D stack:28224 pid:11846 tgid:11844 ppid:5824   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x672/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f02abd5d04e
RSP: 002b:00007f02a9fd3e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f02a9fd56c0 RCX: 00007f02abd5d04e
RDX: 0000000000000020 RSI: 00007f02a9fd4000 RDI: 0000000000000008
RBP: 0000000000000000 R08: 00007f02a9fd3f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 00007f02a9fd3f58 R14: 00007f02a9fd4000 R15: 0000000000000000
 </TASK>
INFO: task syz.4.1558:11861 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.1558      state:D stack:26472 pid:11861 tgid:11860 ppid:5838   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x672/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcfe255d04e
RSP: 002b:00007fcfe3470e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fcfe34726c0 RCX: 00007fcfe255d04e
RDX: 000000000000001c RSI: 00007fcfe3471000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 00007fcfe3470f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00007fcfe3470f58 R14: 00007fcfe3471000 R15: 0000000000000000
 </TASK>
INFO: task syz.0.1561:11871 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1561      state:D stack:27200 pid:11871 tgid:11870 ppid:5823   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 ____sys_sendmsg+0x972/0x9f0 net/socket.c:2698
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2752
 __sys_sendmsg net/socket.c:2784 [inline]
 __do_sys_sendmsg net/socket.c:2789 [inline]
 __se_sys_sendmsg net/socket.c:2787 [inline]
 __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2787
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f981799c819
RSP: 002b:00007f981887b028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9817c15fa0 RCX: 00007f981799c819
RDX: 0000000000000000 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f9817a32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9817c16038 R14: 00007f9817c15fa0 R15: 00007ffdad6722b8
 </TASK>
INFO: task syz.0.1561:11872 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1561      state:D stack:27488 pid:11872 tgid:11870 ppid:5823   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x672/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f981795d04e
RSP: 002b:00007f9818858e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f981885a6c0 RCX: 00007f981795d04e
RDX: 0000000000000028 RSI: 00007f9818859000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007f9818858f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007f9818858f58 R14: 00007f9818859000 R15: 0000000000000000
 </TASK>
INFO: task syz.0.1561:11874 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1561      state:D stack:28120 pid:11874 tgid:11870 ppid:5823   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7183
 __schedule_loop kernel/sched/core.c:7262 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7277
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7334
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 genl_lock net/netlink/genetlink.c:35 [inline]
 genl_op_lock net/netlink/genetlink.c:60 [inline]
 genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x672/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f981795d04e
RSP: 002b:00007f9818816e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f98188186c0 RCX: 00007f981795d04e
RDX: 0000000000000028 RSI: 00007f9818817000 RDI: 0000000000000009
RBP: 0000000000000000 R08: 00007f9818816f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007f9818816f58 R14: 00007f9818817000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e95d020 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5584:
 #0: ffff88803298a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
1 lock held by udevd/9502:
 #0: ffff888026d46350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:953
6 locks held by syz.3.1551/11837:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 #2: ffff888026d95260 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_genl_reconfigure+0x4c1/0x1ea0 drivers/block/nbd.c:2364
 #3: ffff888026c60698 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:1097 [inline]
 #3: ffff888026c60698 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x263/0x680 drivers/block/nbd.c:354
 #4: ffff888026c60060 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_freeze_queue include/linux/blk-mq.h:956 [inline]
 #4: ffff888026c60060 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0 block/blk-settings.c:590
 #5: ffff888026c60098 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_freeze_queue include/linux/blk-mq.h:956 [inline]
 #5: ffff888026c60098 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0 block/blk-settings.c:590
2 locks held by syz.1.1553/11842:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.2.1554/11845:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.2.1554/11846:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.4.1558/11861:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.0.1561/11871:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.0.1561/11872:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.0.1561/11874:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11879:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11881:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11883:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11891:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11895:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11929:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11930:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11933:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11940:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11944:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11979:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11981:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11983:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11996:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/11999:
 #0: ffffffff8fe3ddc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff8fe3dc00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208

=============================================

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 03/18/2026
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: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+0xfaa/0x1000 kernel/hung_task.c:515
 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: 1004 Comm: kworker/u8:7 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x3a/0xb0 kernel/rcu/tree.c:752
Code: e8 db 81 08 0a 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 90 67 27 8e 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 7c 8c 86 00 48 c7 c3 d8 e9 3e 93 49 03 1e 48 89
RSP: 0018:ffffc9000549f5e8 EFLAGS: 00000246
RAX: 1ffffffff1c4ecf3 RBX: 0000000000000001 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8c27efe0 RDI: ffffffff8c27efa0
RBP: ffffffff821c7259 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff940000112a1 R12: 0000000000000002
R13: ffffffff8e95d020 R14: ffffffff8e276798 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125345000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6cb1347e20 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x5f/0x350 kernel/locking/lockdep.c:5831
 rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 rcu_read_lock include/linux/rcupdate.h:838 [inline]
 __pte_offset_map+0x45/0x240 mm/pgtable-generic.c:288
 pte_offset_map_lock+0x46/0x210 mm/pgtable-generic.c:398
 __text_poke+0x2d3/0x9a0 arch/x86/kernel/alternative.c:2575
 text_poke arch/x86/kernel/alternative.c:2660 [inline]
 smp_text_poke_batch_finish+0x923/0x1160 arch/x86/kernel/alternative.c:2993
 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146
 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210
 static_key_enable+0x1a/0x20 kernel/jump_label.c:223
 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:900
 process_one_work kernel/workqueue.c:3288 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3371
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3452
 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>