INFO: task syz.5.879:3051 blocked for more than 122 seconds. Not tainted 6.12.30-syzkaller-g15178d63ac5e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.879 state:D stack:0 pid:3051 tgid:3051 ppid:1327 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x132b/0x1e00 kernel/sched/core.c:7789 __schedule_loop kernel/sched/core.c:7870 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7885 request_wait_answer fs/fuse/dev.c:476 [inline] __fuse_request_send fs/fuse/dev.c:491 [inline] __fuse_simple_request+0xdb1/0x1980 fs/fuse/dev.c:586 fuse_simple_request fs/fuse/fuse_i.h:1248 [inline] fuse_flush+0x909/0x1d50 fs/fuse/file.c:582 filp_flush fs/open.c:1550 [inline] filp_close+0xbd/0x160 fs/open.c:1563 __range_close fs/file.c:712 [inline] __close_range+0x50e/0x6c0 fs/file.c:769 __do_sys_close_range fs/open.c:1616 [inline] __se_sys_close_range fs/open.c:1613 [inline] __x64_sys_close_range+0x7e/0x90 fs/open.c:1613 x64_sys_call+0x1686/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:437 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: 0033:0x7f2d17f8e9a9 RSP: 002b:00007ffe49702328 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 0000000000019853 RCX: 00007f2d17f8e9a9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f2d181b7ba0 R08: 0000000000000001 R09: 0000000d4970261f R10: 00007f2d17e00000 R11: 0000000000000246 R12: 00007f2d181b5fac R13: 00007f2d181b5fa0 R14: ffffffffffffffff R15: 00007ffe49702440 INFO: task syz.8.1081:3708 blocked for more than 123 seconds. Not tainted 6.12.30-syzkaller-g15178d63ac5e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.1081 state:D stack:0 pid:3708 tgid:3708 ppid:1877 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x132b/0x1e00 kernel/sched/core.c:7789 __schedule_loop kernel/sched/core.c:7870 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7885 request_wait_answer fs/fuse/dev.c:476 [inline] __fuse_request_send fs/fuse/dev.c:491 [inline] __fuse_simple_request+0xdb1/0x1980 fs/fuse/dev.c:586 fuse_simple_request fs/fuse/fuse_i.h:1248 [inline] fuse_flush+0x909/0x1d50 fs/fuse/file.c:582 filp_flush fs/open.c:1550 [inline] filp_close+0xbd/0x160 fs/open.c:1563 __range_close fs/file.c:712 [inline] __close_range+0x50e/0x6c0 fs/file.c:769 __do_sys_close_range fs/open.c:1616 [inline] __se_sys_close_range fs/open.c:1613 [inline] __x64_sys_close_range+0x7e/0x90 fs/open.c:1613 x64_sys_call+0x1686/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:437 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: 0033:0x7febac58e9a9 RSP: 002b:00007ffddd6e5c18 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007febac7b7ba0 RCX: 00007febac58e9a9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007febac7b7ba0 R08: 00000000000000c8 R09: 0000000bdd6e5f0f R10: 00007febac7b7ac0 R11: 0000000000000246 R12: 000000000001e0f7 R13: 00007febac7b6080 R14: ffffffffffffffff R15: 00007ffddd6e5d30 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.30-syzkaller-g15178d63ac5e #0 2e49b5e8bba3abd4e44f2eeb6ccfddb4f386a3cf Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 542 Comm: kworker/1:5 Not tainted 6.12.30-syzkaller-g15178d63ac5e #0 2e49b5e8bba3abd4e44f2eeb6ccfddb4f386a3cf Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_in+0x7b/0xc0 drivers/tty/serial/8250/8250_port.c:406 Code: e8 6a 37 6e 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 2b 32 c4 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:ffffc9000c2f7010 EFLAGS: 00000002 RAX: 1ffffffff113b500 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 000000000001d453 RDI: 000000000001d454 RBP: ffffc9000c2f7030 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: ffffffff83177360 R12: dffffc0000000000 R13: 00000000000026d3 R14: ffffffff889dada8 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f71d701cf98 CR3: 00000001042a8000 CR4: 00000000003526b0 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 drivers/tty/serial/8250/8250_port.c:2069 [inline] fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3315 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3337 [inline] serial8250_console_write+0x147a/0x2130 drivers/tty/serial/8250/8250_port.c:3422 univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396 console_emit_next_record kernel/printk/printk.c:3132 [inline] console_flush_all+0x5e6/0xaa0 kernel/printk/printk.c:3220 __console_flush_and_unlock kernel/printk/printk.c:3279 [inline] console_unlock+0xe9/0x270 kernel/printk/printk.c:3319 vprintk_emit+0x27c/0x640 kernel/printk/printk.c:2443 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:4962 hub_port_connect drivers/usb/core/hub.c:5462 [inline] hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] port_event drivers/usb/core/hub.c:5837 [inline] hub_event+0x232d/0x4270 drivers/usb/core/hub.c:5919 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