INFO: task syz.0.17:6458 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:27176 pid:6458 tgid:6458 ppid:6341 task_flags:0x400040 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5263 [inline]
__schedule+0x1836/0x4ed0 kernel/sched/core.c:6871
__schedule_loop kernel/sched/core.c:6953 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6968
request_wait_answer fs/fuse/dev.c:585 [inline]
__fuse_request_send fs/fuse/dev.c:599 [inline]
__fuse_simple_request+0x11d2/0x1bb0 fs/fuse/dev.c:693
fuse_simple_request fs/fuse/fuse_i.h:1251 [inline]
fuse_flush+0x5d4/0x800 fs/fuse/file.c:494
filp_flush+0xbd/0x190 fs/open.c:1544
filp_close+0x1d/0x40 fs/open.c:1557
__range_close fs/file.c:790 [inline]
__do_sys_close_range fs/file.c:849 [inline]
__se_sys_close_range+0x359/0x650 fs/file.c:813
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f891df8eec9
RSP: 002b:00007ffdeb019a38 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 0000000000020713 RCX: 00007f891df8eec9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f891e1e7da0 R08: 0000000000000001 R09: 0000000ceb019d2f
R10: 0000001b30420000 R11: 0000000000000246 R12: 00007f891e1e5fac
R13: 00007f891e1e5fa0 R14: ffffffffffffffff R15: 00007ffdeb019b50
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e33d9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e33d9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e33d9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:11/3006:
2 locks held by getty/5592:
#0: ffff88814f1ba0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by syz-executor/6705:
#0: ffffffff8ee84b88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ee84b88 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8ee84b88 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f6f4f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f6f4f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f6f4f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
#2: ffffffff8e343478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e343478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/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+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfb5/0x1000 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 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: 6705 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 4e a5 9c fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 0f 42 03 fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 da 73 42 06 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc9000475e650 EFLAGS: 00000002
RAX: 1ffffffff33f7400 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffffff99fba410 R08: ffff888024640237 R09: 1ffff110048c8046
R10: dffffc0000000000 R11: ffffffff85255a00 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff99fba180 R15: 0000000000000000
FS: 000055555e5f3500(0000) GS:ffff888125a6f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa28dd17d60 CR3: 00000000598ee000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0xd1/0x2f0 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+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3129 [inline]
console_flush_one_record kernel/printk/printk.c:3215 [inline]
console_flush_all+0x745/0xb60 kernel/printk/printk.c:3289
__console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3359
vprintk_emit+0x4d3/0x5d0 kernel/printk/printk.c:2426
_printk+0xcf/0x120 kernel/printk/printk.c:2451
netdev_info+0x10a/0x160 net/core/dev.c:12967
__dev_set_promiscuity+0x2e8/0x750 net/core/dev.c:9539
netif_set_promiscuity+0x50/0xe0 net/core/dev.c:9574
dev_set_promiscuity+0x126/0x260 net/core/dev_api.c:287
hsr_portdev_setup net/hsr/hsr_slave.c:155 [inline]
hsr_add_port+0x5ce/0x980 net/hsr/hsr_slave.c:211
hsr_dev_finalize+0x685/0xaa0 net/hsr/hsr_device.c:768
hsr_newlink+0x8ad/0x9f0 net/hsr/hsr_netlink.c:128
rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3840
__rtnl_newlink net/core/rtnetlink.c:3957 [inline]
rtnl_newlink+0x16e7/0x1c90 net/core/rtnetlink.c:4072
rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:746
__sys_sendto+0x3bd/0x520 net/socket.c:2248
__do_sys_sendto net/socket.c:2255 [inline]
__se_sys_sendto net/socket.c:2251 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2251
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa28cf90d5c
Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b
RSP: 002b:00007ffc3c1e5160 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa28dd14620 RCX: 00007fa28cf90d5c
RDX: 0000000000000048 RSI: 00007fa28dd14670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffc3c1e51b4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fa28dd14670 R15: 0000000000000000