rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 0-...!: (1 GPs behind) idle=0c9/1/0x4000000000000000 softirq=9375/9376 fqs=0
(detected by 1, t=10505 jiffies, g=11065, q=108)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3561 Comm: udevd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__lock_release kernel/locking/lockdep.c:5309 [inline]
RIP: 0010:lock_release+0x21c/0x8a0 kernel/locking/lockdep.c:5643
Code: 89 e7 48 8b 74 24 08 e8 b2 39 5f 08 44 89 7c 24 3c 44 89 fa 85 c0 0f 84 d2 01 00 00 4d 85 e4 0f 84 0d 03 00 00 4d 8d 74 24 24 <4c> 89 f0 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 a7 04 00 00 41 83
RSP: 0018:ffffc90000007b80 EFLAGS: 00000086
RAX: 0000000000000001 RBX: 000000000000000a RCX: 0000000000000001
RDX: 0000000000000002 RSI: ffffffff964e2b40 RDI: ffff88807d3ca900
RBP: ffffc90000007c90 R08: ffffffff8d89f02f R09: 1ffffffff1b13e05
R10: dffffc0000000000 R11: fffffbfff1b13e06 R12: ffff88807d3ca900
R13: dffffc0000000000 R14: ffff88807d3ca924 R15: 0000000000000002
FS: 00007f446a952880(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9be8d174b8 CR3: 000000002a0f1000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:158 [inline]
_raw_spin_unlock_irqrestore+0x6d/0x120 kernel/locking/spinlock.c:194
debug_hrtimer_deactivate kernel/time/hrtimer.c:415 [inline]
__run_hrtimer kernel/time/hrtimer.c:1653 [inline]
__hrtimer_run_queues+0x2b9/0xb70 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
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804
Code: be ff ff ff ff e8 3c 52 68 08 85 c0 74 4a 4d 85 ff 75 66 0f 1f 44 00 00 48 89 df e8 e6 bd 71 08 e8 61 e6 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 c9 09 fe ff 43 80 3c
RSP: 0018:ffffc90002e7f2e8 EFLAGS: 00000286
RAX: 82697e8e30445000 RBX: ffff8880b903a340 RCX: 82697e8e30445000
RDX: dffffc0000000000 RSI: ffffffff8a2b2800 RDI: ffffffff8a79fe00
RBP: 1ffff11017207613 R08: ffff8880b903a343 R09: 1ffff11017207468
R10: dffffc0000000000 R11: ffffed1017207469 R12: 1ffff110172075c1
R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000
finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921
context_switch kernel/sched/core.c:5052 [inline]
__schedule+0x11f7/0x43c0 kernel/sched/core.c:6395
preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6799
irqentry_exit+0x63/0x70 kernel/entry/common.c:432
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5671
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc90002e7f6d8 EFLAGS: 00000206
RAX: 82697e8e30445000 RBX: ffff88807d3c9dc0 RCX: 82697e8e30445000
RDX: 0000000000000000 RSI: ffffffff8a2b3aa0 RDI: ffffffff8a79fe00
RBP: 0000000000000000 R08: ffffffff8d89f02f R09: 1ffffffff1b13e05
R10: dffffc0000000000 R11: fffffbfff1b13e06 R12: 0000000000000001
R13: 0000000000000246 R14: ffffffff8c31ebe0 R15: ffff88807d3ca8d8
lock_is_held include/linux/lockdep.h:287 [inline]
___might_sleep+0xea/0x610 kernel/sched/core.c:9624
might_alloc include/linux/sched/mm.h:209 [inline]
slab_pre_alloc_hook+0x42/0xc0 mm/slab.h:492
slab_alloc_node mm/slub.c:3139 [inline]
slab_alloc mm/slub.c:3233 [inline]
__kmalloc+0x6b/0x330 mm/slub.c:4408
kmalloc include/linux/slab.h:612 [inline]
kzalloc include/linux/slab.h:738 [inline]
tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
tomoyo_encode+0x27e/0x540 security/tomoyo/realpath.c:80
tomoyo_realpath_from_path+0x5cd/0x610 security/tomoyo/realpath.c:288
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x23f/0x5d0 security/tomoyo/file.c:822
security_inode_getattr+0xcf/0x120 security/security.c:1349
vfs_getattr+0x26/0x3a0 fs/stat.c:157
vfs_statx+0x14e/0x500 fs/stat.c:225
vfs_fstatat fs/stat.c:243 [inline]
__do_sys_newfstatat fs/stat.c:411 [inline]
__se_sys_newfstatat fs/stat.c:405 [inline]
__x64_sys_newfstatat+0x15f/0x200 fs/stat.c:405
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: 0033:0x7f446aaaab0a
Code: 48 8b 15 f1 f2 0d 00 f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 41 89 ca b8 06 01 00 00 0f 05 <3d> 00 f0 ff ff 77 07 31 c0 c3 0f 1f 40 00 48 8b 15 b9 f2 0d 00 f7
RSP: 002b:00007ffd3d796778 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 00007ffd3d796c10 RCX: 00007f446aaaab0a
RDX: 00007ffd3d796780 RSI: 00007ffd3d796c10 RDI: 00000000ffffff9c
RBP: 000055e94875e910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd3d796810
R13: 000055e9264a9100 R14: 000055e948779970 R15: 00007ffd3d797230
rcu: rcu_preempt kthread starved for 10505 jiffies! g11065 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:26960 pid: 15 ppid: 2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2117
rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 1
CPU: 1 PID: 5195 Comm: syz.1.278 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487
print_other_cpu_stall+0x1110/0x1270 kernel/rcu/tree_stall.h:592
check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
rcu_pending kernel/rcu/tree.c:3936 [inline]
rcu_sched_clock_irq+0x843/0x1120 kernel/rcu/tree.c:2619
update_process_times+0x193/0x200 kernel/time/timer.c:2021
tick_sched_handle kernel/time/tick-sched.c:254 [inline]
tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
__run_hrtimer kernel/time/hrtimer.c:1685 [inline]
__hrtimer_run_queues+0x4b4/0xb70 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
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_many_cond+0xbb5/0xd90 kernel/smp.c:969
Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 b9 62 0b 00 83 e3 01 75 07 e8 4f 5f 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7
RSP: 0018:ffffc9000154fbe0 EFLAGS: 00000246
RAX: ffffffff816dd568 RBX: 0000000000000001 RCX: 0000000000080000
RDX: ffffc90004c69000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000154fd20 R08: ffffffff901d524f R09: 1ffffffff203aa49
R10: dffffc0000000000 R11: fffffbfff203aa4a R12: ffff8880b9042848
R13: 1ffff11017208509 R14: ffff8880b913b3c0 R15: 0000000000000000
on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1134
on_each_cpu include/linux/smp.h:71 [inline]
hardware_enable_all+0x7a/0x120 virt/kvm/kvm_main.c:4921
kvm_create_vm virt/kvm/kvm_main.c:1148 [inline]
kvm_dev_ioctl_create_vm virt/kvm/kvm_main.c:4754 [inline]
kvm_dev_ioctl+0x1239/0x2070 virt/kvm/kvm_main.c:4809
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: 0033:0x7fdaf48b4dd9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fdaf2b0e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fdaf4b2dfa0 RCX: 00007fdaf48b4dd9
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000005
RBP: 00007fdaf494ad69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdaf4b2e038 R14: 00007fdaf4b2dfa0 R15: 00007ffdf00e9878