INFO: task syz.2.673:2701 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.673 state:D stack:0 pid:2701 tgid:2701 ppid:291 flags:0x00004006 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_flush+0x909/0x1d50 fs/fuse/file.c:582 filp_flush fs/open.c:1550 [inline] filp_close+0xc0/0x160 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: 0033:0x7f450ab8eba9 RSP: 002b:00007ffd167b5488 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: ffffffffffffffda RBX: 0000000000012239 RCX: 00007f450ab8eba9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f450add7da0 R08: 0000000000000001 R09: 00000014167b577f R10: 0000001b2df20000 R11: 0000000000000246 R12: 00007f450add5fac R13: 00007f450add5fa0 R14: ffffffffffffffff R15: 00007ffd167b55a0 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 7dd95e4db5dfeba9bec18e378df2347c8fceb7ef Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+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: 0 Comm: swapper/1 Not tainted syzkaller #0 7dd95e4db5dfeba9bec18e378df2347c8fceb7ef Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__sanitizer_cov_trace_pc+0x61/0x70 kernel/kcov.c:235 Code: c8 0b 00 00 83 fa 02 75 21 48 8b 91 d0 0b 00 00 48 8b 32 48 8d 7e 01 8b 89 cc 0b 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 <5d> c3 cc cc cc cc cc 0f 1f 84 00 00 00 00 00 b8 f6 a7 90 14 90 90 RSP: 0018:ffffc90000230ca0 EFLAGS: 00000046 RAX: ffffffff81439597 RBX: ffff8881f6f28600 RCX: ffff88810366df00 RDX: 0000000000000100 RSI: 00000000004650d6 RDI: 00000000004650d6 RBP: ffffc90000230ca0 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520000461b0 R12: 1ffff1103ede50c0 R13: 00000000004650d6 R14: dffffc0000000000 R15: 00000000004650d6 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f12cf3a3ad8 CR3: 0000000120756000 CR4: 00000000003526b0 Call Trace: kvm_steal_clock+0x137/0x170 arch/x86/kernel/kvm.c:419 paravirt_steal_clock arch/x86/include/asm/paravirt.h:49 [inline] update_rq_clock_task kernel/sched/core.c:821 [inline] update_rq_clock+0x6a7/0x7c0 kernel/sched/core.c:860 _nohz_idle_balance+0x3bd/0x5a0 kernel/sched/fair.c:12954 nohz_idle_balance kernel/sched/fair.c:13001 [inline] sched_balance_softirq+0x8a/0x170 kernel/sched/fair.c:13229 handle_softirqs+0x1ab/0x630 kernel/softirq.c:621 __do_softirq kernel/softirq.c:659 [inline] invoke_softirq kernel/softirq.c:476 [inline] __irq_exit_rcu+0x48/0xc0 kernel/softirq.c:708 irq_exit_rcu+0xd/0x30 kernel/softirq.c:720 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline] sysvec_call_function_single+0x7f/0x90 arch/x86/kernel/smp.c:266 asm_sysvec_call_function_single+0x1f/0x30 arch/x86/include/asm/idtentry.h:709 RIP: 0010:pv_native_safe_halt+0x17/0x20 arch/x86/kernel/paravirt.c:106 Code: cc cc cc b8 e1 fb a8 8f 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 93 f1 3a 00 f3 0f 1e fa 55 48 89 e5 fb f4 <5d> c3 cc cc cc cc cc cc cc b8 00 00 00 00 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900001a7e00 EFLAGS: 000002c6 RAX: ffff8881f6f00000 RBX: ffff88810366df00 RCX: ffffffff858c60ae RDX: 0000000000000001 RSI: 0000000000000004 RDI: 000000000024ca84 RBP: ffffc900001a7e00 R08: ffff8881f6f39733 R09: 1ffff1103ede72e6 R10: dffffc0000000000 R11: ffffed103ede72e7 R12: 1ffff110206cdbe0 R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff87cb0ce8 arch_safe_halt arch/x86/include/asm/paravirt.h:112 [inline] default_idle+0x17/0x30 arch/x86/kernel/process.c:754 arch_cpu_idle+0xd/0x20 arch/x86/kernel/process.c:791 default_idle_call+0x3f/0x80 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x1a0/0x470 kernel/sched/idle.c:326 cpu_startup_entry+0x48/0x70 kernel/sched/idle.c:424 start_secondary+0x12e/0x140 arch/x86/kernel/smpboot.c:314 common_startup_64+0x13b/0x157