INFO: task syz.1.172:861 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.172 state:D stack:0 pid:861 tgid:855 ppid:291 flags:0x00004004
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_timeout+0xb2/0x3a0 kernel/time/timer.c:2595
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common+0x359/0x630 kernel/sched/completion.c:127
wait_for_completion_state+0x19/0x40 kernel/sched/completion.c:264
coredump_wait fs/coredump.c:419 [inline]
do_coredump+0x7cf/0x2bd0 fs/coredump.c:581
get_signal+0x11fd/0x14f0 kernel/signal.c:2918
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]
irqentry_exit_to_user_mode+0x4e/0xb0 kernel/entry/common.c:231
irqentry_exit+0x16/0x60 kernel/entry/common.c:334
exc_invalid_op+0x42/0x60 arch/x86/kernel/traps.c:354
asm_exc_invalid_op+0x1f/0x30 arch/x86/include/asm/idtentry.h:621
RIP: 0033:0x200000000004
RSP: 002b:00007fd70a992a78 EFLAGS: 00010286
RAX: 00000000000000cc RBX: 00007fd709de6090 RCX: 00007fd709b8f6c9
RDX: 00007fd70a992a80 RSI: 00007fd70a992bb0 RDI: 000000000000000d
RBP: 00007fd709c11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd709de6128 R14: 00007fd709de6090 R15: 00007ffc6c8eb958
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 756 Comm: kworker/1:4 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_in+0x7b/0xc0 drivers/tty/serial/8250/8250_port.c:406
Code: e8 0a f5 6c 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 6b 62 c3 fe 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f 5d e9 85 b1 76 02 cc 44 89 f9 80 e1
RSP: 0018:ffffc9000e9ff010 EFLAGS: 00000006
RAX: 1ffffffff113eb05 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 00000000000069b1 RDI: 00000000000069b2
RBP: ffffc9000e9ff030 R08: 0000000000000003 R09: 0000000000000004
R10: 0000000000000000 R11: ffffffff83190950 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff889f5fe8 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007facfd5b5c98 CR3: 000000011d0d8000 CR4: 00000000003526b0
Call Trace:
serial_port_in include/linux/serial_core.h:794 [inline]
serial8250_console_write+0x328/0x2130 drivers/tty/serial/8250/8250_port.c:3385
univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396
console_emit_next_record kernel/printk/printk.c:3151 [inline]
console_flush_all+0x5e6/0xaa0 kernel/printk/printk.c:3239
__console_flush_and_unlock kernel/printk/printk.c:3298 [inline]
console_unlock+0xe9/0x270 kernel/printk/printk.c:3338
vprintk_emit+0x27c/0x640 kernel/printk/printk.c:2462
dev_vprintk_emit+0x33b/0x400 drivers/base/core.c:4962
dev_printk_emit+0xe1/0x130 drivers/base/core.c:4973
__dev_printk+0x17f/0x1b0 drivers/base/core.c:4985
_dev_info+0x10b/0x160 drivers/base/core.c:5031
hub_port_init+0x5fb/0x27b0 drivers/usb/core/hub.c:4990
hub_port_connect drivers/usb/core/hub.c:5490 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5701 [inline]
port_event drivers/usb/core/hub.c:5865 [inline]
hub_event+0x232d/0x4270 drivers/usb/core/hub.c:5947
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d2/0x1020 kernel/workqueue.c:3319
worker_thread+0xc58/0x1250 kernel/workqueue.c:3400
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244