INFO: task syz.2.1342:4806 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1342 state:D stack:0 pid:4806 tgid:4805 ppid:296 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:6027 [inline] __schedule+0x14ce/0x2100 kernel/sched/core.c:7894 __schedule_loop kernel/sched/core.c:7975 [inline] schedule+0xc5/0x240 kernel/sched/core.c:7990 request_wait_answer fs/fuse/dev.c:477 [inline] __fuse_request_send fs/fuse/dev.c:493 [inline] __fuse_simple_request+0xdee/0x1b10 fs/fuse/dev.c:588 fuse_simple_request fs/fuse/fuse_i.h:1248 [inline] fuse_flush+0xad9/0x2020 fs/fuse/file.c:602 filp_flush fs/open.c:1552 [inline] filp_close+0xc0/0x160 fs/open.c:1565 __range_close fs/file.c:726 [inline] __close_range+0x344/0x4e0 fs/file.c:796 __do_sys_close_range fs/open.c:1618 [inline] __se_sys_close_range fs/open.c:1615 [inline] __x64_sys_close_range+0x7e/0x90 fs/open.c:1615 x64_sys_call+0x1686/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:437 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f810dd9ce59 RSP: 002b:00007f810eceb028 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 00007f810e015fa0 RCX: 00007f810dd9ce59 RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000000000000000 RBP: 00007f810de32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f810e016038 R14: 00007f810e015fa0 R15: 00007ffcae6acf68 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 cd47f8e0083a5f781c340422d7a309d6c8dfd054 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2ba/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+0xdad/0xf00 kernel/hung_task.c:423 kthread+0x2c9/0x370 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 430 Comm: kworker/0:4 Not tainted syzkaller #0 cd47f8e0083a5f781c340422d7a309d6c8dfd054 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_in+0x7b/0xc0 drivers/tty/serial/8250/8250_port.c:406 Code: e8 1a 4f 63 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 0b f1 bb fe 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f 5d e9 d5 1a 86 02 cc 44 89 f9 80 e1 RSP: 0018:ffffc9000db16230 EFLAGS: 00000006 RAX: 1ffffffff1188205 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: 00000000000202d1 RDI: 00000000000202d2 RBP: ffffc9000db16250 R08: 0000000000000003 R09: 0000000000000004 R10: 0000000000000000 R11: ffffffff832478c0 R12: dffffc0000000000 R13: dffffc0000000000 R14: ffffffff88c41488 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1dbf7ea2f8 CR3: 000000011a7f0000 CR4: 00000000003526b0 Call Trace: serial_port_in include/linux/serial_core.h:794 [inline] serial8250_console_write+0x33a/0x21a0 drivers/tty/serial/8250/8250_port.c:3391 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+0x5fa/0xac0 kernel/printk/printk.c:3239 __console_flush_and_unlock kernel/printk/printk.c:3298 [inline] console_unlock+0xf8/0x2c0 kernel/printk/printk.c:3338 vprintk_emit+0x282/0x650 kernel/printk/printk.c:2462 dev_vprintk_emit+0x359/0x420 drivers/base/core.c:4962 dev_printk_emit+0xef/0x150 drivers/base/core.c:4973 __netdev_printk+0x3f2/0x4e0 net/core/dev.c:12031 netdev_warn+0x11f/0x180 net/core/dev.c:12084 smsc95xx_read_reg drivers/net/usb/smsc95xx.c:102 [inline] smsc95xx_eeprom_confirm_not_busy drivers/net/usb/smsc95xx.c:344 [inline] smsc95xx_read_eeprom+0x4e3/0x680 drivers/net/usb/smsc95xx.c:369 smsc95xx_init_mac_address drivers/net/usb/smsc95xx.c:818 [inline] smsc95xx_bind+0x3d6/0x1490 drivers/net/usb/smsc95xx.c:1133 usbnet_probe+0x9c0/0x2a40 drivers/net/usb/usbnet.c:1779 usb_probe_interface+0x6ac/0xc00 drivers/usb/core/driver.c:400 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2d5/0x890 drivers/base/dd.c:657 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957 bus_for_each_drv+0x267/0x300 drivers/base/bus.c:459 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534 device_add+0x80c/0xbf0 drivers/base/core.c:3692 usb_set_configuration+0x1acf/0x20b0 drivers/usb/core/message.c:2268 usb_generic_driver_probe+0x95/0x160 drivers/usb/core/generic.c:254 usb_probe_device+0x1d4/0x380 drivers/usb/core/driver.c:295 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2d5/0x890 drivers/base/dd.c:657 __driver_probe_device+0x198/0x280 drivers/base/dd.c:799 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957 bus_for_each_drv+0x267/0x300 drivers/base/bus.c:459 __device_attach+0x2c9/0x3c0 drivers/base/dd.c:1029 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534 device_add+0x80c/0xbf0 drivers/base/core.c:3692 usb_new_device+0x9f8/0x15b0 drivers/usb/core/hub.c:2703 hub_port_connect drivers/usb/core/hub.c:5574 [inline] hub_port_connect_change drivers/usb/core/hub.c:5714 [inline] port_event drivers/usb/core/hub.c:5878 [inline] hub_event+0x30c6/0x4700 drivers/usb/core/hub.c:5960 process_one_work kernel/workqueue.c:3261 [inline] process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3342 worker_thread+0xc51/0x1370 kernel/workqueue.c:3423 kthread+0x2c9/0x370 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