INFO: task kworker/u8:0:12 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0 state:D stack:0 pid:12 tgid:12 ppid:2 flags:0x00004000
Workqueue: events_unbound linkwatch_event
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
linkwatch_event+0x12/0x60 net/core/link_watch.c:285
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d5/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
INFO: task syz-executor:3940 blocked for more than 123 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:3940 tgid:3940 ppid:1 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rtnl_lock+0x19/0x20 net/core/rtnetlink.c:79
tun_detach drivers/net/tun.c:698 [inline]
tun_chr_close+0x41/0x150 drivers/net/tun.c:3517
__fput+0x1fe/0xa00 fs/file_table.c:429
____fput+0x20/0x30 fs/file_table.c:457
task_work_run+0x1e3/0x250 kernel/task_work.c:240
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9bc/0x2630 kernel/exit.c:953
do_group_exit+0x22a/0x300 kernel/exit.c:1095
get_signal+0x139d/0x14f0 kernel/signal.c:2933
arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218
do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7efdb1390a23
RSP: 002b:00007fff9562aad8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: 0000000000000040 RBX: 00007efdb20f4620 RCX: 00007efdb1390a23
RDX: 0000000000000040 RSI: 00007efdb20f4670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fff9562aaf4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007efdb20f4670 R15: 0000000000000000
INFO: task syz-executor:3952 blocked for more than 125 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:3952 tgid:3952 ppid:1 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
rtnl_lock net/core/rtnetlink.c:79 [inline]
rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675
netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2555
rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696
netlink_unicast_kernel net/netlink/af_netlink.c:1323 [inline]
netlink_unicast+0x8c3/0xa60 net/netlink/af_netlink.c:1349
netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1899
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
__sys_sendto+0x66a/0x6f0 net/socket.c:2217
__do_sys_sendto net/socket.c:2229 [inline]
__se_sys_sendto net/socket.c:2225 [inline]
__x64_sys_sendto+0xe9/0x100 net/socket.c:2225
x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ff7fcd90a23
RSP: 002b:00007fffb2801188 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007ff7fdaf4620 RCX: 00007ff7fcd90a23
RDX: 0000000000000028 RSI: 00007ff7fdaf4670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007fffb28011a4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003
R13: 0000000000000000 R14: 00007ff7fdaf4670 R15: 0000000000000000
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 cbcc7fb1a3c48ec238a6a34dd578fa775d2dddba
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xd8f/0xed0 kernel/hung_task.c:423
kthread+0x2c7/0x370 kernel/kthread.c:389
ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3969 Comm: syz-executor Not tainted syzkaller #0 cbcc7fb1a3c48ec238a6a34dd578fa775d2dddba
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:io_serial_in+0x7b/0xc0 drivers/tty/serial/8250/8250_port.c:406
Code: e8 4a 62 6d fe 44 89 f9 d3 e3 49 83 c6 08 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 eb 96 c3 fe 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 f9 80 e1
RSP: 0018:ffffc9000076f0d0 EFLAGS: 00000006
RAX: 1ffffffff113df05 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc9000076f0f0 R08: 0000000000000003 R09: 0000000000000004
R10: 0000000000000000 R11: ffffffff83188170 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff889efde8 R15: 0000000000000000
FS: 000055557ab05500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055942cd3bb98 CR3: 0000000168fca000 CR4: 00000000003526b0
Call Trace:
serial_port_in include/linux/serial_core.h:794 [inline]
serial8250_console_write+0x325/0x2130 drivers/tty/serial/8250/8250_port.c:3386
univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396
console_emit_next_record kernel/printk/printk.c:3152 [inline]
console_flush_all+0x5e3/0xaa0 kernel/printk/printk.c:3240
__console_flush_and_unlock kernel/printk/printk.c:3299 [inline]
console_unlock+0xe9/0x270 kernel/printk/printk.c:3339
vprintk_emit+0x27c/0x640 kernel/printk/printk.c:2463
vprintk_default+0x2a/0x40 kernel/printk/printk.c:2478
vprintk+0x93/0xa0 kernel/printk/printk_safe.c:73
_printk+0xd0/0x120 kernel/printk/printk.c:2488
__show_mem+0x243f/0x28c0 mm/show_mem.c:441
warn_alloc_show_mem+0x157/0x290 mm/page_alloc.c:3968
warn_alloc+0x1c8/0x2a0 mm/page_alloc.c:3994
__vmalloc_area_node mm/vmalloc.c:3664 [inline]
__vmalloc_node_range_noprof+0x68e/0x1420 mm/vmalloc.c:3864
vmalloc_user_noprof+0x77/0x90 mm/vmalloc.c:4024
kcov_ioctl+0x5d/0x5c0 kernel/kcov.c:716
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0x132/0x1b0 fs/ioctl.c:893
__x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893
x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7ff6e138e7eb
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffe7336ecf0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000080000 RCX: 00007ff6e138e7eb
RDX: 0000000000080000 RSI: ffffffff80086301 RDI: 00000000000000db
RBP: 00007ff6e15c6308 R08: 00000000000000da R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000
net_ratelimit: 123507 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:22:4c:d9:cb:2f:26, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)