INFO: task syz.3.869:9047 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.869       state:D stack:26352 pid:9047  tgid:9046  ppid:5625   task_flags:0x480140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 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:2106 [inline]
 nbd_genl_reconfigure+0x7e9/0x1e80 drivers/block/nbd.c:2410
 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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x54e/0x850 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: 0033:0x7efd7199de99
RSP: 002b:00007efd7288d028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007efd71c25fa0 RCX: 00007efd7199de99
RDX: 0000000020000080 RSI: 0000200000000b40 RDI: 000000000000000a
RBP: 00007efd71a33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007efd71c26038 R14: 00007efd71c25fa0 R15: 00007ffc282250f8
 </TASK>
INFO: task syz.4.870:9051 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.870       state:D stack:27872 pid:9051  tgid:9049  ppid:5624   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 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+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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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: 0033:0x7f971555e6ce
RSP: 002b:00007f9716463e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f97164656c0 RCX: 00007f971555e6ce
RDX: 0000000000000020 RSI: 00007f9716464000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 00007f9716463f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000007
R13: 00007f9716463f58 R14: 00007f9716464000 R15: 0000000000000000
 </TASK>
INFO: task syz.4.870:9059 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.870       state:D stack:27872 pid:9059  tgid:9049  ppid:5624   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 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+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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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: 0033:0x7f971555e6ce
RSP: 002b:00007f9716442e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f97164446c0 RCX: 00007f971555e6ce
RDX: 0000000000000020 RSI: 00007f9716443000 RDI: 0000000000000008
RBP: 0000000000000000 R08: 00007f9716442f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000008
R13: 00007f9716442f58 R14: 00007f9716443000 R15: 0000000000000000
 </TASK>
INFO: task syz.0.878:9084 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.878       state:D stack:27248 pid:9084  tgid:9083  ppid:5623   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 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+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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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: 0033:0x7fa80fb5e6ce
RSP: 002b:00007fa810a68e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa810a6a6c0 RCX: 00007fa80fb5e6ce
RDX: 0000000000000020 RSI: 00007fa810a69000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007fa810a68f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00007fa810a68f58 R14: 00007fa810a69000 R15: 0000000000000000
 </TASK>
INFO: task syz.2.882:9120 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.882       state:D stack:28496 pid:9120  tgid:9119  ppid:5626   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 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+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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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: 0033:0x7f0be755e6ce
RSP: 002b:00007f0be8509e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f0be850b6c0 RCX: 00007f0be755e6ce
RDX: 0000000000000020 RSI: 00007f0be850a000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007f0be8509f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 00007f0be8509f58 R14: 00007f0be850a000 R15: 0000000000000000
 </TASK>
INFO: task syz.2.882:9122 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.882       state:D stack:25768 pid:9122  tgid:9119  ppid:5626   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 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+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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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: 0033:0x7f0be755e6ce
RSP: 002b:00007f0be84e8e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f0be84ea6c0 RCX: 00007f0be755e6ce
RDX: 0000000000000028 RSI: 00007f0be84e9000 RDI: 0000000000000009
RBP: 0000000000000000 R08: 00007f0be84e8f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007f0be84e8f58 R14: 00007f0be84e9000 R15: 0000000000000000
 </TASK>
INFO: task syz.1.883:9124 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.883       state:D stack:27952 pid:9124  tgid:9123  ppid:5622   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 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+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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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: 0033:0x7f1e8975e6ce
RSP: 002b:00007f1e879f4e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f1e879f66c0 RCX: 00007f1e8975e6ce
RDX: 000000000000001c RSI: 00007f1e879f5000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007f1e879f4f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007f1e879f4f58 R14: 00007f1e879f5000 R15: 0000000000000000
 </TASK>
INFO: task syz.1.883:9128 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.883       state:D stack:28808 pid:9128  tgid:9123  ppid:5622   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7383
 __mutex_lock_common kernel/locking/mutex.c:726 [inline]
 __mutex_lock+0x7bf/0x1550 kernel/locking/mutex.c:821
 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+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+0x13a/0x180 net/socket.c:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 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: 0033:0x7f1e8975e6ce
RSP: 002b:00007f1e879d3e88 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f1e879d56c0 RCX: 00007f1e8975e6ce
RDX: 000000000000001c RSI: 00007f1e879d4000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007f1e879d3f04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: 00007f1e879d3f58 R14: 00007f1e879d4000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/u8:0/12:
 #0: ffff8880b863b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
 #1: ffff8880b8624440 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x57/0x7d0 kernel/sched/psi.c:933
 #2: ffff8880b8626058 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
 #2: ffff8880b8626058 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1a9/0xed0 kernel/time/timer.c:1085
 #3: ffff8880b8624440 (psi_seq){-.-.}-{0:0}, at: psi_task_change+0xc9/0x320 kernel/sched/psi.c:919
 #4: ffff8880b8626058 (&base->lock){-.-.}-{2:2}, at: lock_timer_base kernel/time/timer.c:1004 [inline]
 #4: ffff8880b8626058 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x1a9/0xed0 kernel/time/timer.c:1085
 #5: ffffffff9a9d34f0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xb7/0x420 lib/debugobjects.c:873
1 lock held by khungtaskd/30:
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by klogd/4981:
 #0: ffff8880b863b160 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:667
2 locks held by getty/5379:
 #0: ffff888035e860a0 (&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+0x45a/0x1360 drivers/tty/n_tty.c:2211
1 lock held by udevd/5637:
 #0: ffff888022b8f350 (&disk->open_mutex
){+.+.}-{4:4}
, at: bdev_open+0xde/0xd70 block/bdev.c:948
6 locks held by syz.3.869/9047:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
 #2: ffff888022f99a60 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_genl_reconfigure+0x4bc/0x1e80 drivers/block/nbd.c:2401
 #3: ffff8880233cb528 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:1103 [inline]
 #3: ffff8880233cb528 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x263/0x680 drivers/block/nbd.c:354
 #4: ffff8880233caef0 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_freeze_queue include/linux/blk-mq.h:956 [inline]
 #4: ffff8880233caef0 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: queue_limits_commit_update_frozen+0x55/0xd0 block/blk-settings.c:590
 #5: ffff8880233caf28 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_freeze_queue include/linux/blk-mq.h:956 [inline]
 #5: ffff8880233caf28 (&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.4.870/9051:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.4.870/9059:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.0.878/9084:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.2.882/9120:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.2.882/9122:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.1.883/9124:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz.1.883/9128:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9160:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9162:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9199:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9200:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9203:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9256:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9258:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9293:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9296:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9300:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9352:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9354:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9389:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9392:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by syz-executor/9396:
 #0: ffffffff9009d5c8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
 #1: ffffffff9009d400 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
2 locks held by dhcpcd/9445:
 #0: ffff88806a100dc0 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
 #0: ffff88806a100dc0 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release net/socket.c:709 [inline]
 #0: ffff88806a100dc0 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: sock_close+0x82/0x220 net/socket.c:1501
 #1: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #1: ffffffff8eb5ff68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 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:122
 nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 47 Comm: kworker/u8:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:check_preemption_disabled+0x22/0xe0 lib/smp_processor_id.c:53
Code: 90 90 90 90 90 90 90 90 55 41 57 41 56 53 65 8b 05 f7 cd 9c 07 65 8b 0d ec cd 9c 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d <e9> c9 e3 02 00 cc 9c 59 f7 c1 00 02 00 00 74 ea 65 4c 8b 3d 9e cd
RSP: 0018:ffffc90000b77758 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8e4b0a4f RDI: ffffffff8c4bda80
RBP: 00000000ffffffff R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200016eee4 R12: 0000000000000046
R13: ffff88801b765d00 R14: ffff8880b863b160 R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff888124f54000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffffb89ef52 CR3: 000000000e946000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
 lock_is_held_type+0xdf/0x150 kernel/locking/lockdep.c:5941
 lock_is_held include/linux/lockdep.h:249 [inline]
 lockdep_assert_rq_held kernel/sched/sched.h:1641 [inline]
 update_rq_clock+0x8f/0x560 kernel/sched/core.c:865
 __schedule+0x53b/0x56c0 kernel/sched/core.c:7115
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 toggle_allocation_gate+0x17c/0x290 mm/kfence/core.c:913
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 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>