INFO: task syz-executor:14197 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:24280 pid:14197 tgid:14197 ppid:1 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7376
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7433
rwsem_down_write_slowpath+0x4c2/0x12a0 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1c0/0x1f0 kernel/locking/rwsem.c:1632
rdma_dev_exit_net+0x174/0x6b0 drivers/infiniband/core/device.c:1156
ops_exit_list net/core/net_namespace.c:200 [inline]
ops_undo_list+0x2ee/0xab0 net/core/net_namespace.c:253
setup_net+0x1fa/0x3a0 net/core/net_namespace.c:459
copy_net_ns+0x345/0x7a0 net/core/net_namespace.c:582
create_new_namespaces+0x3ea/0xac0 kernel/nsproxy.c:132
unshare_nsproxy_namespaces+0xf2/0x220 kernel/nsproxy.c:234
ksys_unshare+0x4a2/0xa70 kernel/fork.c:3297
__do_sys_unshare kernel/fork.c:3361 [inline]
__se_sys_unshare kernel/fork.c:3359 [inline]
__x64_sys_unshare+0x31/0x40 kernel/fork.c:3359
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c5a79f427
RSP: 002b:00007ffdf9ff51f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f7c5aa25f40 RCX: 00007f7c5a79f427
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f7c5aa267b8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008
R13: 0000000000000003 R14: 00007ffdf9ff5438 R15: 0000000000000000
Showing all locks held in the system:
locks held by kworker/0:0/9: 3, on CPU#0:
#0: ffff88801c05b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc900000e7d08 (netdev_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: netdev_work_proc+0x71/0x880 net/core/netdev_work.c:132
locks held by pr/ttyS0/16: 2, last CPU#0:
#0: ffffffff8edd88b8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
#0: ffffffff8edd88b8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline]
#0: ffffffff8edd88b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x49/0x60 kernel/printk/printk.c:291
#1: ffffffff9bc75f38 (&port_lock_key){-.-.}-{3:3}, at: __uart_port_lock_irqsave include/linux/serial_core.h:613 [inline]
#1: ffffffff9bc75f38 (&port_lock_key){-.-.}-{3:3}, at: univ8250_console_device_lock+0x64/0xc0 drivers/tty/serial/8250/8250_core.c:413
locks held by khungtaskd/32: 1, last CPU#1:
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6871
locks held by kworker/u8:6/227: 5, last CPU#1:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc900030afd08 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff8ec7cb10 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0x12/0x20 kernel/jump_label.c:222
#3: ffffffff8ef41500 (jump_label_mutex){+.+.}-{4:4}, at: jump_label_lock kernel/jump_label.c:27 [inline]
#3: ffffffff8ef41500 (jump_label_mutex){+.+.}-{4:4}, at: static_key_enable_cpuslocked+0xb5/0x270 kernel/jump_label.c:207
#4: ffffffff8ec9c480 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
locks held by klogd/4956: 1, last CPU#1:
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x2090 arch/x86/kernel/unwind_orc.c:495
locks held by dhcpcd/5262: 1, on CPU#1:
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x1bd/0x1f10 net/ipv4/devinet.c:1120
locks held by getty/5353: 2, on CPU#1:
#0: ffff888037a6e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900032262e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
locks held by syz-executor/5584: 2, last CPU#1:
#0: ffff88802c4e1bc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff88802c4e1bc0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa00 mm/mmap.c:1299
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by kworker/u8:12/5866: 3, on CPU#0:
#0: ffff88803445b940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc90005257d08 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#2: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x12/0x30 net/ipv6/addrconf.c:4770
locks held by kworker/u8:13/6777: 3, on CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc9000b417d08 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:313
locks held by kworker/u8:15/6814: 2, on CPU#0:
#0: ffff88801c094140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc9001dd9fd08 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
locks held by kworker/u8:16/8173: 4, last CPU#1:
#0: ffff88801d2e0940 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc900047dfd08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:677
#3: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
#3: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:249
locks held by syz-executor/14189: 2, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x174/0x6b0 drivers/infiniband/core/device.c:1156
locks held by syz-executor/14192: 2, on CPU#1:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x174/0x6b0 drivers/infiniband/core/device.c:1156
locks held by syz-executor/14197: 2, on CPU#1:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x174/0x6b0 drivers/infiniband/core/device.c:1156
locks held by syz-executor/14242: 2, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x174/0x6b0 drivers/infiniband/core/device.c:1156
locks held by syz-executor/14251: 2, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x21e/0x780 net/ipv4/ip_tunnel.c:1136
locks held by syz-executor/14263: 2, on CPU#1:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_exit_net+0x174/0x6b0 drivers/infiniband/core/device.c:1156
locks held by syz-executor/14266: 4, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
#3: ffff88807f275020 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0x112/0x820 drivers/infiniband/core/device.c:976
locks held by syz-executor/14281: 6, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
#3: ffff88807f275020 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0x112/0x820 drivers/infiniband/core/device.c:976
#4: ffff88807f275310 (&rxe->usdev_lock){+.+.}-{4:4}, at: rxe_query_port+0x115/0x330 drivers/infiniband/sw/rxe/rxe_verbs.c:55
#5: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: ib_get_eth_speed+0x128/0xb80 drivers/infiniband/core/verbs.c:2060
locks held by syz-executor/14334: 4, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
#3: ffff88807f275020 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0x112/0x820 drivers/infiniband/core/device.c:976
locks held by syz-executor/14348: 3, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14363: 3, on CPU#1:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14369: 3, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14381: 3, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14420: 3, on CPU#1:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14433: 3, on CPU#1:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14446: 3, on CPU#1:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14450: 3, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by syz-executor/14463: 3, on CPU#0:
#0: ffffffff90cbbf48 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x323/0x7a0 net/core/net_namespace.c:578
#1: ffffffff908e3168 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1221
#2: ffffffff908e2ee8 (rdma_nets_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x2ff/0x590 drivers/infiniband/core/device.c:1226
locks held by kworker/0:3/14464: 3, on CPU#0:
#0: ffff88801c05b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1466/0x1b10 kernel/workqueue.c:3371
#1: ffffc900035f7d08 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0xa2c/0x1b10 kernel/workqueue.c:3372
#2: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
locks held by syz-executor/14515: 1, on CPU#1:
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:366 [inline]
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xac3/0x2620 net/core/rtnetlink.c:4219
locks held by syz-executor/14527: 1, on CPU#0:
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x31c/0x18c0 net/ipv4/devinet.c:978
locks held by syz-executor/14534: 1, on CPU#1:
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:134 [inline]
#0: ffffffff90cd4b40 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x31c/0x18c0 net/ipv4/devinet.c:978
locks held by syz-executor/14540: 2, last CPU#1:
#0: ffff8880268f0340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#0: ffff8880268f0340 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1f5/0x470 mm/util.c:579
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by modprobe/14542: 1, last CPU#1:
#0: ffff88807d71e540 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:544 [inline]
#0: ffff88807d71e540 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x22c/0xa00 mm/mmap.c:1323
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 32 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:410
Code: a3 5a fc 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c e9 bd 15 24 06 e8 88 0d ce fc eb a2 e8 11 0e
RSP: 0018:ffffc90000157958 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff85b1a170 RDI: ffffffff9bc75f60
RBP: ffffffff9bc75f20 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 205d323354202020 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff378ec41 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123b4f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5bdd66a4ee CR3: 0000000079115000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:2013
serial8250_fifo_wait_for_lsr_thre+0x5f/0xd0 drivers/tty/serial/8250/8250_port.c:3270
__serial8250_console_fifo_write+0xa5/0x290 drivers/tty/serial/8250/8250_port.c:3345
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
__serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline]
serial8250_console_write+0xf46/0x1330 drivers/tty/serial/8250/8250_port.c:3493
nbcon_emit_next_record+0x8f7/0xa70 kernel/printk/nbcon.c:1070
nbcon_emit_one+0x1a8/0x2b0 kernel/printk/nbcon.c:1157
nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245