rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=36d4/1/0x4000000000000000 softirq=24355/24359 fqs=62
rcu: 	(detected by 0, t=10502 jiffies, g=20925, q=1801 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 6486 Comm: cmp Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:151 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198
Code: 48 89 f3 49 89 fe 48 83 c7 18 48 8b 74 24 10 e8 d5 87 cc f5 4c 89 f7 e8 2d fd cc f5 f7 c3 00 02 00 00 74 05 e8 90 dd f8 f5 9c <58> a9 00 02 00 00 75 27 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00
RSP: 0018:ffffc90000a08db8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000046 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b87281c0
RBP: ffff888077e51300 R08: ffff8880b87281c3 R09: 1ffff110170e5038
R10: dffffc0000000000 R11: ffffed10170e5039 R12: ffff8880b87281c0
R13: ffffffff89dc9af0 R14: ffff8880b87281c0 R15: 1ffff110170e5062
FS:  0000000000000000(0000) GS:ffff88812504c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fea8b492a10 CR3: 000000007369e000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __run_hrtimer kernel/time/hrtimer.c:2028 [inline]
 __hrtimer_run_queues+0x2bf/0xa10 kernel/time/hrtimer.c:2096
 hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:generic_fillattr+0x4ff/0x840 fs/stat.c:108
Code: ff 4d 8b 27 4c 8d bb 80 00 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 fa e3 eb ff 4d 89 27 8b 6c 24 04 89 ee <81> e6 00 00 00 40 31 ff e8 14 4b 7e ff 81 e5 00 00 00 40 75 0a e8
RSP: 0018:ffffc90003d3fc20 EFLAGS: 00000246
RAX: 1ffff920007a7fc0 RBX: ffffc90003d3fd80 RCX: 000000000000000c
RDX: 0000000000000000 RSI: 00000000000007ff RDI: 0000000000000020
RBP: 00000000000007ff R08: ffffffff90576c37 R09: 1ffffffff20aed86
R10: dffffc0000000000 R11: fffffbfff20aed87 R12: 0000000000000308
R13: dffffc0000000000 R14: ffff88802ab90ba0 R15: ffffc90003d3fe00
 ext4_getattr+0x6ec/0x8a0 fs/ext4/inode.c:6263
 ext4_file_getattr+0x72/0x310 fs/ext4/inode.c:6274
 vfs_getattr_nosec+0x2e1/0x430 fs/stat.c:213
 vfs_getattr fs/stat.c:262 [inline]
 vfs_fstat fs/stat.c:281 [inline]
 __do_sys_newfstat fs/stat.c:551 [inline]
 __se_sys_newfstat fs/stat.c:546 [inline]
 __x64_sys_newfstat+0x165/0x270 fs/stat.c:546
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fea8b7bee87
Code: 00 00 00 b8 15 00 00 00 0f 05 48 3d 00 f0 ff ff 77 01 c3 f7 d8 89 05 28 44 01 00 b8 ff ff ff ff c3 66 90 b8 05 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 f7 d8 89 05 08 44 01 00 b8 ff ff ff ff
RSP: 002b:00007fff8693c8b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 00007fea8b794ab0 RCX: 00007fea8b7bee87
RDX: 0000000000000003 RSI: 00007fff8693c950 RDI: 0000000000000003
RBP: 00007fff8693ca10 R08: 00007fea8b496690 R09: 00007fea8b794ab0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fff8693cab0 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 10190 jiffies! g20925 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:27832 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x17d9/0x56c0 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x164/0x2b0 kernel/sched/core.c:7326
 schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2123
 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2325
 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: 6140 Comm: udevd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: 89 fb e8 23 00 00 00 48 8b 3d f4 5e 89 0c 48 89 de 5b e9 83 12 62 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 98 3e a6 11 65 8b 15 b9 3e a6
RSP: 0000:ffffc90003117818 EFLAGS: 00000202
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff888027823e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003117970 R08: ffffffff90576c37 R09: 1ffffffff20aed86
R10: dffffc0000000000 R11: fffffbfff20aed87 R12: 1ffff110170e8211
R13: ffff8880b863c648 R14: ffff8880b8741088 R15: 0000000000000001
FS:  00007f193403e880(0000) GS:ffff888124f4c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005635bb1fab40 CR3: 0000000035dd8000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 csd_lock_wait kernel/smp.c:342 [inline]
 smp_call_function_many_cond+0x11fd/0x15f0 kernel/smp.c:912
 on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1077
 __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+0x5c4/0x1090 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:3941 [inline]
 do_wp_page+0x3d52/0x4c70 mm/memory.c:4336
 handle_pte_fault mm/memory.c:6395 [inline]
 __handle_mm_fault mm/memory.c:6517 [inline]
 handle_mm_fault+0x1490/0x3080 mm/memory.c:6686
 do_user_addr_fault+0xa4d/0x1340 arch/x86/mm/fault.c:1343
 handle_page_fault arch/x86/mm/fault.c:1483 [inline]
 exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f19338b5dfe
Code: 00 00 66 0f ef c0 41 0f 11 44 24 20 49 89 54 24 10 49 89 74 24 18 4c 89 66 10 4c 89 62 18 48 89 c2 48 83 ca 01 49 89 54 24 08 <49> 89 04 04 48 83 c4 10 5b 41 5c 41 5d c3 0f 1f 40 00 48 89 cf 48
RSP: 002b:00007ffef5507140 EFLAGS: 00010202
RAX: 0000000000005600 RBX: 0000000000000c40 RCX: 00005635bb1ffda0
RDX: 0000000000005601 RSI: 00007f19339f1b20 RDI: 00005635bb1f9f00
RBP: 00007f19339f1ac0 R08: 0000000000000c40 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005635bb1f5540
R13: 00007f19339f1ac0 R14: 0000000000000c40 R15: 00007f19339f1ac0
 </TASK>