rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=a3ec/1/0x4000000000000000 softirq=104499/104504 fqs=25
rcu: 	(detected by 0, t=10505 jiffies, g=119165, q=316 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 19831 Comm: syz.8.3306 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:debug_lockdep_rcu_enabled+0x29/0x40 kernel/rcu/update.c:321
Code: 90 f3 0f 1e fa 31 c0 83 3d 63 d7 7a 04 00 74 1d 83 3d 1a 09 7b 04 00 74 14 65 48 8b 0d 58 15 88 07 31 c0 83 b9 8c 0b 00 00 00 <0f> 94 c0 e9 4a 96 57 f5 cc cc cc cc cc cc cc cc cc cc cc cc cc cc
RSP: 0018:ffffc90000a08d00 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff888029bc02e8 RCX: ffff88801e323d80
RDX: 0000000000010000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000141190 R12: ffff888029bc0300
R13: ffff888029bc0000 R14: dffffc0000000000 R15: ffff88807e289800
FS:  00007f4184fd36c0(0000) GS:ffff888125314000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b34017ff8 CR3: 000000006289a000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 advance_sched+0x142/0xc90 net/sched/sch_taprio.c:933
 __run_hrtimer kernel/time/hrtimer.c:1930 [inline]
 __hrtimer_run_queues+0x3c0/0xa20 kernel/time/hrtimer.c:1994
 hrtimer_interrupt+0x44b/0x950 kernel/time/hrtimer.c:2113
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1067
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x47/0x80 kernel/locking/spinlock.c:198
Code: f7 e8 8d 24 e7 f5 f7 c3 00 02 00 00 74 05 e8 90 af 12 f6 9c 58 a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> d4 a6 d8 f5 65 8b 05 1d 73 85 07 85 c0 74 18 5b 41 5e e9 ec f3
RSP: 0018:ffffc90004ee7b20 EFLAGS: 00000206
RAX: 0000000000000006 RBX: 0000000000000206 RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8dfd7f08 RDI: 0000000000000001
RBP: ffff88805727bd80 R08: ffffffff903380f7 R09: 1ffffffff206701e
R10: dffffc0000000000 R11: fffffbfff206701f R12: dffffc0000000000
R13: 1ffff110170e779c R14: ffff88805727c7f0 R15: ffff8880b873bce0
 class_raw_spinlock_irqsave_destructor include/linux/spinlock.h:571 [inline]
 try_to_wake_up+0x7b4/0x1380 kernel/sched/core.c:4190
 wake_up_process kernel/sched/core.c:4434 [inline]
 wake_up_q+0x85/0xd0 kernel/sched/core.c:1158
 futex_wake+0x49a/0x580 kernel/futex/waitwake.c:198
 do_futex+0x395/0x420 kernel/futex/syscalls.c:135
 __do_sys_futex kernel/futex/syscalls.c:207 [inline]
 __se_sys_futex+0x3a8/0x450 kernel/futex/syscalls.c:188
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f418719c819
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:00007f4184fd30e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f4187416278 RCX: 00007f418719c819
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f418741627c
RBP: 00007f4187416270 R08: 3fffffffffffffff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4187416308 R14: 00007fff61c2dae0 R15: 00007fff61c2dbc8
 </TASK>
rcu: rcu_preempt kthread starved for 10380 jiffies! g119165 f0x0 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:27968 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7282
 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 19717 Comm: udevd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: 8b 3d 24 df 63 0c 48 89 de 5b e9 63 ea 5f 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d 08 ef 7a 11 65 8b 15 29 ef 7a 11 81 e2 00 01 ff 00 74
RSP: 0000:ffffc9000345f838 EFLAGS: 00000202
RAX: ffffffff81b9d866 RBX: ffff8880b863c148 RCX: ffff88802df23d80
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000345f970 R08: ffffffff903380f7 R09: 1ffffffff206701e
R10: dffffc0000000000 R11: fffffbfff206701f R12: 1ffff110170e8169
R13: dffffc0000000000 R14: ffff8880b8740b48 R15: 0000000000000001
FS:  00007f3dd6290880(0000) GS:ffff888125214000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055842dfd5a38 CR3: 0000000022ec4000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 csd_lock_wait kernel/smp.c:342 [inline]
 smp_call_function_many_cond+0xfe6/0x13d0 kernel/smp.c:892
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1057
 __flush_tlb_multi arch/x86/include/asm/paravirt.h:46 [inline]
 flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
 flush_tlb_mm_range+0x5c3/0x10b0 arch/x86/mm/tlb.c:1451
 flush_tlb_page arch/x86/include/asm/tlbflush.h:345 [inline]
 ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:104
 wp_page_copy mm/memory.c:3925 [inline]
 do_wp_page+0x3da7/0x4cc0 mm/memory.c:4320
 handle_pte_fault mm/memory.c:6427 [inline]
 __handle_mm_fault mm/memory.c:6549 [inline]
 handle_mm_fault+0x151d/0x3170 mm/memory.c:6718
 do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f3dd6317a9a
Code: 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 53 48 85 ff 74 2f 48 8b 47 08 48 39 c7 74 21 48 8b 1f 48 39 df 74 19 48 89 18 <48> 89 43 08 e8 8d d9 ff ff 48 89 d8 5b c3 0f 1f 84 00 00 00 00 00
RSP: 002b:00007ffc1d7c91f0 EFLAGS: 00010202
RAX: 000055842dfd60b0 RBX: 000055842dfd5a30 RCX: 0000000000000000
RDX: 000055842dfe1430 RSI: 000055842dfddf60 RDI: 000055842dfdb4e0
RBP: 000055842dfdb4e0 R08: 000055842dfddf70 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000297 R12: 000055841fc24588
R13: 00007ffc1d7c92a0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>