INFO: task syz.6.1210:11045 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.6.1210 state:D
stack:24248 pid:11045 tgid:11030 ppid:9082 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common+0x2fc/0x4e0 kernel/sched/completion.c:121
disable_device+0x16f/0x280 drivers/infiniband/core/device.c:1325
__ib_unregister_device+0x2b4/0x480 drivers/infiniband/core/device.c:1555
ib_unregister_device_and_put+0x5a/0x80 drivers/infiniband/core/device.c:1620
nldev_dellink+0x21f/0x320 drivers/infiniband/core/nldev.c:1827
rdma_nl_rcv_msg+0x38a/0x6e0 drivers/infiniband/core/netlink.c:195
rdma_nl_rcv_skb.constprop.0.isra.0+0x2d0/0x430 drivers/infiniband/core/netlink.c:239
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x8c8/0xdd0 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa5d/0xc30 net/socket.c:2592
___sys_sendmsg+0x134/0x1d0 net/socket.c:2646
__sys_sendmsg+0x16d/0x220 net/socket.c:2678
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd6b138f749
RSP: 002b:00007fd6b21fe038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fd6b15e6270 RCX: 00007fd6b138f749
RDX: 0000000000000000 RSI: 00002000000002c0 RDI: 000000000000000c
RBP: 00007fd6b1413f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd6b15e6308 R14: 00007fd6b15e6270 R15: 00007ffda57883e8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c96a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c96a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c96a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
2 locks held by getty/5579:
#0: ffff88814e7b40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x1510 drivers/tty/n_tty.c:2211
4 locks held by kworker/u8:23/7835:
#0: ffff88801badc948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x128d/0x1b20 kernel/workqueue.c:3232
#1: ffffc900033d7c90 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x914/0x1b20 kernel/workqueue.c:3233
#2: ffffffff9012b3d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xad/0x830 net/core/net_namespace.c:670
#3: ffff88807ad6c700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1703
2 locks held by syz.6.1210/11045:
#0: ffffffff9af7abd8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg+0x169/0x6e0 drivers/infiniband/core/netlink.c:164
#1: ffff88807ad6c700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x23b/0x480 drivers/infiniband/core/device.c:1551
2 locks held by syz.3.1482/12169:
#0: ffffffff9012b3d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x333/0x7c0 net/core/net_namespace.c:577
#1: ffff88807ad6c700 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x30/0x320 drivers/infiniband/core/device.c:1703
2 locks held by syz.7.1489/12189:
#0: ffffffff9af7abd8 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg+0x169/0x6e0 drivers/infiniband/core/netlink.c:164
#1: ffff88807ad6c700 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x23b/0x480 drivers/infiniband/core/device.c:1551
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x133/0x180 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xe66/0x1180 kernel/hung_task.c:515
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12571 Comm: kworker/0:5 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events dvb_usb_read_remote_control
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: e9 4d 1b 5e 00 be 03 00 00 00 5b e9 12 dd ed 02 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 34 24 <65> 48 8b 15 98 c9 f3 11 65 8b 05 a9 c9 f3 11 a9 00 01 ff 00 74 1d
RSP: 0018:ffffc9000469f4f8 EFLAGS: 00000097
RAX: 0000000000000000 RBX: 0000000000000005 RCX: ffffffff853263d1
RDX: ffff88802c340000 RSI: ffffffff853263e0 RDI: 0000000000000001
RBP: ffffffff9aeedbc0 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: ffff88802c340b30 R12: 0000000000000000
R13: 0000000000000020 R14: fffffbfff35ddbd2 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881248f5000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d2dbff8 CR3: 000000005ed56000 CR4: 00000000003526f0
Call Trace:
io_serial_in+0x60/0xb0 drivers/tty/serial/8250/8250_port.c:399
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:1961
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0xf81/0x1890 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3129 [inline]
console_flush_one_record+0x796/0xc60 kernel/printk/printk.c:3215
console_flush_all kernel/printk/printk.c:3289 [inline]
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xef/0x240 kernel/printk/printk.c:3359
vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426
_printk+0xc7/0x100 kernel/printk/printk.c:2451
dvb_usb_generic_rw+0x270/0x490 drivers/media/usb/dvb-usb/dvb-usb-urb.c:36
cxusb_ctrl_msg+0x118/0x200 drivers/media/usb/dvb-usb/cxusb.c:102
cxusb_rc_query+0x8d/0x150 drivers/media/usb/dvb-usb/cxusb.c:520
dvb_usb_read_remote_control+0xdd/0x1c0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:261
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246