rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
(detected by 1, t=10502 jiffies, g=8277, q=122)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294955908-4294945406), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g8277 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:28064 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4398 Comm: syz.0.22 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x1b/0x60 kernel/kcov.c:206
Code: 89 de 5b e9 d7 9e 43 00 00 00 cc cc 00 00 cc 48 8b 04 24 65 48 8b 0d a4 a3 8a 7e 65 8b 15 a5 a3 8a 7e 81 e2 00 01 ff 00 74 11 <81> fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c 8b 91 10 16 00
RSP: 0018:ffffc90000007d18 EFLAGS: 00000006
RAX: ffffffff8167b95f RBX: 0000000000000001 RCX: ffff888029d65940
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: ffffc90000007e98 R08: dffffc0000000000 R09: ffffed1017205449
R10: ffffed1017205449 R11: 1ffff11017205448 R12: ffff8880b902a2d0
R13: 1ffff1101720545a R14: 0000000000000000 R15: dffffc0000000000
FS: 000055557cabc500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31b63fff CR3: 000000001fe21000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
cpu_max_bits_warn include/linux/cpumask.h:108 [inline]
cpumask_check include/linux/cpumask.h:115 [inline]
cpumask_test_cpu include/linux/cpumask.h:344 [inline]
cpu_online include/linux/cpumask.h:895 [inline]
trace_hrtimer_expire_entry include/trace/events/timer.h:236 [inline]
__run_hrtimer kernel/time/hrtimer.c:1682 [inline]
__hrtimer_run_queues+0x46f/0xc40 kernel/time/hrtimer.c:1749
hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
Code: 74 05 e8 be 9a d2 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> d6 22 a6 f7 65 8b 05 67 20 57 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc900036cf380 EFLAGS: 00000206
RAX: ece30d54b52e6b00 RBX: 0000000000000a06 RCX: ece30d54b52e6b00
RDX: dffffc0000000000 RSI: ffffffff8a0b1be0 RDI: 0000000000000001
RBP: ffffc900036cf410 R08: dffffc0000000000 R09: fffffbfff1ff543e
R10: fffffbfff1ff543e R11: 1ffffffff1ff543d R12: dffffc0000000000
R13: 0000000000000000 R14: ffff8880b902a240 R15: 1ffff920006d9e70
hrtimer_start include/linux/hrtimer.h:420 [inline]
stimer_start arch/x86/kvm/hyperv.c:-1 [inline]
kvm_hv_process_stimers+0x12ff/0x1aa0 arch/x86/kvm/hyperv.c:863
vcpu_enter_guest+0x2fc8/0x7110 arch/x86/kvm/x86.c:9872
vcpu_run arch/x86/kvm/x86.c:10181 [inline]
kvm_arch_vcpu_ioctl_run+0xdea/0x1f40 arch/x86/kvm/x86.c:10418
kvm_vcpu_ioctl+0x887/0xb80 virt/kvm/kvm_main.c:3894
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f36ba239749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe1e96eab8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f36ba48ffa0 RCX: 00007f36ba239749
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00007f36ba2bdf91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f36ba48ffa0 R14: 00007f36ba48ffa0 R15: 0000000000000003
</TASK>
sched: RT throttling activated