INFO: task syz.2.337:1510 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.337 state:D stack:0 pid:1510 tgid:1509 ppid:292 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 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_lookup_name+0x2db/0x990 fs/fuse/dir.c:526 fuse_lookup+0x2ad/0x18f0 fs/fuse/dir.c:624 __lookup_slow+0x2d7/0x400 fs/namei.c:1732 lookup_slow+0x57/0x80 fs/namei.c:1749 walk_component+0x302/0x440 fs/namei.c:2053 lookup_last fs/namei.c:2556 [inline] path_lookupat+0x180/0x4a0 fs/namei.c:2580 filename_lookup+0x1f5/0x520 fs/namei.c:2609 vfs_statx+0x101/0x200 fs/stat.c:312 vfs_fstatat+0xe5/0x1d0 fs/stat.c:341 __do_sys_newfstatat fs/stat.c:505 [inline] __se_sys_newfstatat+0xcd/0x340 fs/stat.c:499 __x64_sys_newfstatat+0x9f/0xc0 fs/stat.c:499 x64_sys_call+0x1821/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:263 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: 0033:0x7f05aff8eec9 RSP: 002b:00007f05b0da5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 00007f05b01e5fa0 RCX: 00007f05aff8eec9 RDX: 0000200000000d00 RSI: 0000200000000cc0 RDI: ffffffffffffff9c RBP: 00007f05b0011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f05b01e6038 R14: 00007f05b01e5fa0 R15: 00007ffecefc1fa8 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 68071847e78a8b5e73ab1b858b320f4e6b4f981b Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 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: 702 Comm: syz.0.108 Not tainted syzkaller #0 68071847e78a8b5e73ab1b858b320f4e6b4f981b Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:io_serial_in+0x7b/0xc0 drivers/tty/serial/8250/8250_port.c:406 Code: e8 1a 24 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 bb 77 c3 fe 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f 5d e9 45 8f 76 02 cc 44 89 f9 80 e1 RSP: 0018:ffffc9000e64eed0 EFLAGS: 00000006 RAX: 1ffffffff113e705 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020 RBP: ffffc9000e64eef0 R08: 0000000000000003 R09: 0000000000000004 R10: 0000000000000000 R11: ffffffff8318db90 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffffff889f3e28 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f626f1566e8 CR3: 000000010b75a000 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:3152 [inline] console_flush_all+0x5e6/0xaa0 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 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_err+0x10b/0x160 drivers/base/core.c:5028 gadget_disconnect+0x82/0x90 drivers/usb/gadget/legacy/raw_gadget.c:389 usb_gadget_disconnect_locked+0x276/0x430 drivers/usb/gadget/udc/core.c:783 gadget_unbind_driver+0xb3/0x3e0 drivers/usb/gadget/udc/core.c:1667 device_remove drivers/base/dd.c:567 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x45f/0x790 drivers/base/dd.c:1295 driver_detach+0x1f5/0x2d0 drivers/base/dd.c:1358 bus_remove_driver+0x254/0x2b0 drivers/base/bus.c:744 driver_unregister+0x79/0xb0 drivers/base/driver.c:274 usb_gadget_unregister_driver+0x52/0x80 drivers/usb/gadget/udc/core.c:1733 raw_release+0xda/0x280 drivers/usb/gadget/legacy/raw_gadget.c:462 __fput+0x1fe/0xa00 fs/file_table.c:429 ____fput+0x20/0x30 fs/file_table.c:457 task_work_run+0x1e0/0x250 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: 0033:0x7ff9fd7c1785 Code: Unable to access opcode bytes at 0x7ff9fd7c175b. RSP: 002b:00007ff9fe56ef80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007ff9fd9e5fa0 RCX: 00007ff9fd7c1785 RDX: 00007ff9fe56efc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ff9fd811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007ff9fd9e6038 R14: 00007ff9fd9e5fa0 R15: 00007ffe9ba75e98