INFO: task syz.5.7840:31436 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.5.7840 state:D stack:28696 pid:31436 tgid:31432 ppid:30664 task_flags:0x400040 flags:0x08080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75
___down_common kernel/locking/semaphore.c:268 [inline]
__down_common+0x321/0x730 kernel/locking/semaphore.c:293
down+0x80/0xd0 kernel/locking/semaphore.c:100
console_lock+0x58/0x90 kernel/printk/printk.c:2896
do_fb_ioctl+0x5f1/0x800 drivers/video/fbdev/core/fb_chrdev.c:86
fb_compat_ioctl+0x34e/0x820 drivers/video/fbdev/core/fb_chrdev.c:293
__do_compat_sys_ioctl fs/ioctl.c:695 [inline]
__se_compat_sys_ioctl fs/ioctl.c:638 [inline]
__ia32_compat_sys_ioctl+0x5ea/0x950 fs/ioctl.c:638
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0x20d/0x640 arch/x86/entry/syscall_32.c:307
do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f13f6c
RSP: 002b:00000000f4f7150c EFLAGS: 00000206 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000004601
RDX: 0000000080000300 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by udevd/5193:
2 locks held by getty/5579:
#0: ffff8880332420a0 (&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+0x45c/0x13c0 drivers/tty/n_tty.c:2211
5 locks held by kworker/1:6/5919:
6 locks held by syz.5.7840/31435:
1 lock held by syz.3.8666/1550:
#0: ffffffff8eff5d48 (tty_mutex){+.+.}-{4:4}, at: tty_release_struct+0xae/0xd0 drivers/tty/tty_io.c:1691
1 lock held by syz.3.8666/1552:
2 locks held by syz.4.8667/1564:
#0: ffffffff8eff5d48 (tty_mutex){+.+.}-{4:4}, at: tty_open_by_driver drivers/tty/tty_io.c:2037 [inline]
#0: ffffffff8eff5d48 (tty_mutex){+.+.}-{4:4}, at: tty_open+0x22d/0xd70 drivers/tty/tty_io.c:2120
#1: ffff88802b0c61c0 (&tty->legacy_mutex){+.+.}-{4:4}, at: tty_init_dev+0x74/0x4d0 drivers/tty/tty_io.c:1406
1 lock held by syz.9.8672/1574:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: be 6b 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 d2 19 00 fb f4 fc e9 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0000:ffffffff8e407dc0 EFLAGS: 00000242
RAX: 0000000002328e51 RBX: ffffffff819a91fa RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8defb811 RDI: ffffffff8c27d500
RBP: ffffffff8e407eb0 R08: ffff8880b863399b R09: 1ffff110170c6733
R10: dffffc0000000000 R11: ffffed10170c6734 R12: 0000000000000000
R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 1ffffffff1c929d8
FS: 0000000000000000(0000) GS:ffff888125454000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000800ed000 CR3: 00000000299ec000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000080083
DR3: ffffffffefffff16 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
rest_init+0x2de/0x300 init/main.c:760
start_kernel+0x385/0x3d0 init/main.c:1210
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147