INFO: task syz.0.3219:10040 blocked for more than 122 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3219      state:D stack:0     pid:10040 tgid:10039 ppid:9411   flags:0x00004004
Call Trace:
 <TASK>
 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
 super_lock+0x150/0x300 fs/super.c:115
 super_lock_shared fs/super.c:140 [inline]
 iterate_supers+0x8a/0x560 fs/super.c:934
 ksys_sync+0x95/0x160 fs/sync.c:103
 __ia32_sys_sync+0x12/0x20 fs/sync.c:114
 x64_sys_call+0x2a58/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:163
 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: 0033:0x7f54b078ebe9
RSP: 002b:00007f54b16c1038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f54b09b5fa0 RCX: 00007f54b078ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f54b09b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f54b09b6038 R14: 00007f54b09b5fa0 R15: 00007ffd981a3b48
 </TASK>
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 a8cf528afde17777b8d0df17d514b1350887467d
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 __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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 a8cf528afde17777b8d0df17d514b1350887467d
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:update_cpu_capacity kernel/sched/fair.c:10294 [inline]
RIP: 0010:update_group_capacity+0x50f/0x9f0 kernel/sched/fair.c:10311
Code: 80 3c 30 00 74 12 4c 89 ff e8 2d 6e 7e 00 48 be 00 00 00 00 00 fc ff df 49 8b 1f 48 83 c3 08 48 89 d8 48 c1 e8 03 80 3c 30 00 <74> 12 48 89 df e8 27 6f 7e 00 48 be 00 00 00 00 00 fc ff df 4c 89
RSP: 0018:ffffc90000007740 EFLAGS: 00000246
RAX: 1ffff110207ca301 RBX: ffff888103e51808 RCX: 00000000000f2a60
RDX: 0000000000000260 RSI: dffffc0000000000 RDI: ffff8881f6e506f0
RBP: ffffc90000007810 R08: ffff888103e512af R09: 1ffff110207ca255
R10: dffffc0000000000 R11: ffffed10207ca256 R12: 00000000000003ca
R13: ffff8881f6e50730 R14: 00000000000003ca R15: ffff888103e51298
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555569d124a8 CR3: 0000000120368000 CR4: 00000000003526b0
Call Trace:
 <IRQ>
 update_sd_lb_stats kernel/sched/fair.c:11331 [inline]
 sched_balance_find_src_group kernel/sched/fair.c:11594 [inline]
 sched_balance_rq+0x89b/0x5060 kernel/sched/fair.c:12041
 sched_balance_domains+0x4b4/0xa10 kernel/sched/fair.c:12507
 _nohz_idle_balance+0x3e3/0x5a0 kernel/sched/fair.c:12958
 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
 </IRQ>
 <TASK>
 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 8c b3 55 00 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 61 3b 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:ffffffff87207da0 EFLAGS: 000002c6
RAX: ffff8881f6e00000 RBX: ffffffff87215540 RCX: ffffffff858bf09e
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 00000000003c4934
RBP: ffffffff87207da0 R08: ffff8881f6e39733 R09: 1ffff1103edc72e6
R10: dffffc0000000000 R11: ffffed103edc72e7 R12: 1ffffffff0e42aa8
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff87cae6e8
 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
 rest_init+0x10b/0x130 init/main.c:748
 start_kernel+0x46a/0x4bb init/main.c:1135
 x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x6a/0x7b arch/x86/kernel/head64.c:488
 common_startup_64+0x13b/0x157
 </TASK>