rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=60577, q=731 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10469 (4294989212-4294978743), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10469 jiffies! g60577 f0x2 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:28984 pid:15    tgid:15    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x145d/0x4a00 kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6960
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
 rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x74f/0xa30 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 2859 Comm: udevd Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:task_irq_context kernel/locking/lockdep.c:4682 [inline]
RIP: 0010:__lock_acquire+0x195/0x2890 kernel/locking/lockdep.c:5174
Code: 84 24 b0 00 00 00 49 89 46 08 48 8b 04 24 49 89 46 18 41 8b b4 24 8c 0a 00 00 31 c0 65 8b 15 aa 74 47 0b 85 f6 0f 95 c0 85 d2 <0f> 95 c2 c1 e3 0f c1 e1 10 0f b6 d2 0f b7 db 41 c1 e0 13 8d 04 50
RSP: 0018:ffffc900001a8ca8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8881f57280d8
RBP: 0000000000000004 R08: 0000000000000001 R09: 000000000000006e
R10: ffffffff8aa491d7 R11: ffff888117b3a7e8 R12: ffff888117b39d40
R13: ffff8881f57280d8 R14: ffff888117b3a888 R15: 0000000000000001
FS:  00007f9d6e24b880(0000) GS:ffff888268cf4000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556a1e24a8 CR3: 0000000117b12000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 lock_acquire kernel/locking/lockdep.c:5868 [inline]
 lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0x36/0x50 kernel/locking/spinlock.c:170
 __run_hrtimer kernel/time/hrtimer.c:1781 [inline]
 __hrtimer_run_queues+0x2bc/0xc40 kernel/time/hrtimer.c:1841
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858
 handle_softirqs+0x208/0x940 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:debug_lockdep_rcu_enabled+0xa/0x40 kernel/rcu/update.c:320
Code: eb b6 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 8b 05 de 96 4d 03 <85> c0 74 20 8b 05 90 a2 4d 03 85 c0 74 16 65 48 8b 05 28 c4 4b 05
RSP: 0018:ffffc9000150f578 EFLAGS: 00000293
RAX: 0000000000000002 RBX: 0000000000000001 RCX: ffffffff81e68023
RDX: ffff888117b39d40 RSI: ffffffff81e6812d RDI: 0000000000000006
RBP: 0000000000000001 R08: 0000000000000006 R09: 0000000000000001
R10: 0000000000000001 R11: ffff888117b3a7e8 R12: ffff888106cbfea0
R13: ffff888106cbfe9c R14: 0000000000000000 R15: dffffc0000000000
 rcu_read_unlock include/linux/rcupdate.h:895 [inline]
 __page_table_check_zero+0x2c2/0x4a0 mm/page_table_check.c:145
 page_table_check_free include/linux/page_table_check.h:43 [inline]
 free_pages_prepare mm/page_alloc.c:1396 [inline]
 __free_frozen_pages+0x7b4/0x1010 mm/page_alloc.c:2943
 discard_slab mm/slub.c:3346 [inline]
 __put_partials+0x130/0x170 mm/slub.c:3886
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4c/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x6f/0xa0 mm/kasan/common.c:405
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __do_kmalloc_node mm/slub.c:5657 [inline]
 __kmalloc_noprof+0x33b/0x8d0 mm/slub.c:5669
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kmalloc_array_noprof include/linux/slab.h:1003 [inline]
 security_inode_init_security+0x113/0x360 security/security.c:1321
 shmem_mknod+0xe9/0x220 mm/shmem.c:3879
 lookup_open.isra.0+0x12a0/0x1750 fs/namei.c:4440
 open_last_lookups fs/namei.c:4540 [inline]
 path_openat+0xa95/0x3140 fs/namei.c:4784
 do_filp_open+0x20b/0x470 fs/namei.c:4814
 do_sys_openat2+0x120/0x260 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x570 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9d6e339407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffc6cdf7350 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9d6e24b880 RCX: 00007f9d6e339407
RDX: 0000000000080141 RSI: 000055f94c79302e RDI: ffffffffffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000000001a4 R11: 0000000000000202 R12: 00000000ffffffff
R13: 00000000ffffffff R14: ffffffffffffffff R15: 0000000000000000
 </TASK>