INFO: task syz-executor680:5659 blocked for more than 143 seconds. INFO: task syz-executor680:5659 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor680 state:D stack:25480 pid:5659 tgid:5657 ppid:5655 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5520 [inline] __schedule+0x17db/0x58f0 kernel/sched/core.c:7270 __schedule_loop kernel/sched/core.c:7347 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7362 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7419 rwsem_down_write_slowpath+0x87d/0x1080 kernel/locking/rwsem.c:1215 __down_write_common kernel/locking/rwsem.c:1347 [inline] __down_write kernel/locking/rwsem.c:1356 [inline] down_write+0x1bc/0x200 kernel/locking/rwsem.c:1632 inode_lock include/linux/fs.h:1024 [inline] process_measurement+0x443/0x1c10 security/integrity/ima/ima_main.c:300 ima_file_check+0xe1/0x130 security/integrity/ima/ima_main.c:685 security_file_post_open+0xb3/0x260 security/security.c:2755 do_open fs/namei.c:4839 [inline] path_openat+0x1485/0x1d60 fs/namei.c:5000 do_file_open+0x23e/0x4a0 fs/namei.c:5029 do_sys_openat2+0x115/0x200 fs/open.c:1417 do_sys_open fs/open.c:1423 [inline] __do_sys_openat fs/open.c:1439 [inline] __se_sys_openat fs/open.c:1434 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1434 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f53dc3ed909 RSP: 002b:00007f53dc3991d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f53dc494e78 RCX: 00007f53dc3ed909 RDX: 00000000000c4842 RSI: 0000200000000300 RDI: 00000000ffffff9c RBP: 00007f53dc494e70 R08: 35203a6b63617473 R09: 35203a6b63617473 R10: 00000000000001ff R11: 0000000000000246 R12: 00007f53dc465890 R13: 0031656c69662f2e R14: 00007ffebc434f20 R15: 0000200000000300 Showing all locks held in the system: locks held by pr/ttyS0/16: 2, last CPU#1: #0: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline] #0: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline] #0: ffffffff8ec36338 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291 #1: ffffffff9ad350d8 (&port_lock_key){-.-.}-{3:3}, at: __uart_port_lock_irqsave include/linux/serial_core.h:613 [inline] #1: ffffffff9ad350d8 (&port_lock_key){-.-.}-{3:3}, at: univ8250_console_device_lock+0x67/0xc0 drivers/tty/serial/8250/8250_core.c:413 locks held by khungtaskd/32: 1, last CPU#0: #0: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6837 locks held by getty/5372: 2, on CPU#1: #0: ffff8880359fc0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor680/5658: 3, last CPU#1: #0: ffff88807f24e460 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2753 [inline] #0: ffff88807f24e460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x22b/0xba0 fs/read_write.c:683 #1: ffff88807697cb80 (&sb->s_type->i_mutex_key#18){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline] #1: ffff88807697cb80 (&sb->s_type->i_mutex_key#18){+.+.}-{4:4}, at: fuse_cache_write_iter fs/fuse/file.c:1510 [inline] #1: ffff88807697cb80 (&sb->s_type->i_mutex_key#18){+.+.}-{4:4}, at: fuse_file_write_iter+0xb7f/0x11b0 fs/fuse/file.c:1869 #2: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #2: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #2: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline] #2: ffffffff8ed5c720 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495 locks held by syz-executor680/5659: 1, on CPU#1: #0: ffff88807697cb80 (&sb->s_type->i_mutex_key#18){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline] #0: ffff88807697cb80 (&sb->s_type->i_mutex_key#18){+.+.}-{4:4}, at: process_measurement+0x443/0x1c10 security/integrity/ima/ima_main.c:300 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123 nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66 trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 16 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409 Code: e8 0e 27 55 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 3f 23 c5 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07 RSP: 0018:ffffc900001578b8 EFLAGS: 00000002 RAX: 1ffffffff35a6a00 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020 RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: ffffffff85729970 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff9ad35100 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124dd6000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d8ac7d3168 CR3: 0000000070420000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x184/0x2f0 drivers/tty/serial/8250/8250_port.c:2013 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline] __serial8250_console_fifo_write+0xcd/0x3e0 drivers/tty/serial/8250/8250_port.c:3345 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline] __serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline] serial8250_console_write+0xaa1/0x1200 drivers/tty/serial/8250/8250_port.c:3493 nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1 nbcon_emit_one kernel/printk/nbcon.c:1157 [inline] nbcon_kthread_func+0x679/0x880 kernel/printk/nbcon.c:1271 kthread+0x38b/0x480 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245