rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10498 ticks this GP) idle=57b/1/0x4000000000000000 softirq=6495/6495 fqs=226 
	(t=10500 jiffies g=7881 q=594)
rcu: rcu_preempt kthread starved for 10037 jiffies! g7881 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:28112 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11c3/0x4350 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/0x11f0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9a/0x370 kernel/rcu/tree.c:2145
 kthread+0x42e/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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:729
NMI backtrace for cpu 1
CPU: 1 PID: 4315 Comm: syz.1.14 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <IRQ>
 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_dump_cpu_stacks+0x22d/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31f/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ec/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+0x4b0/0xb60 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x397/0x8b0 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:__sanitizer_cov_trace_const_cmp8+0x7a/0x80 kernel/kcov.c:302
Code: c1 e0 05 4d 8d 50 28 4d 39 ca 77 1e 4a c7 44 02 08 07 00 00 00 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a <c3> 0f 1f 44 00 00 48 8b 46 08 48 8d 48 ff 48 89 c2 48 31 ca 48 39
RSP: 0018:ffffc9000323f840 EFLAGS: 00000297
RAX: ffffffff8135fd28 RBX: 000000005dcad150 RCX: ffff88807a713b80
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000323fb20 R08: ffff88805dcad3f0 R09: 00000000800c0009
R10: dffffc0000000000 R11: fffffbfff1b1631e R12: ffffea0000000000
R13: ffff88805dcad690 R14: 000000000000002e R15: 0000000000000000
 phys_addr_valid arch/x86/mm/physaddr.h:7 [inline]
 __phys_addr+0xa8/0x170 arch/x86/mm/physaddr.c:28
 virt_to_head_page include/linux/mm.h:911 [inline]
 ___cache_free+0x2a/0x120 mm/slub.c:3511
 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc+0x15d/0x280 mm/slub.c:3238
 kmem_cache_zalloc include/linux/slab.h:728 [inline]
 locks_alloc_lock fs/locks.c:346 [inline]
 fcntl_setlk+0xa5/0x1060 fs/locks.c:2449
 do_fcntl+0x533/0x1360 fs/fcntl.c:373
 __do_sys_fcntl fs/fcntl.c:466 [inline]
 __se_sys_fcntl+0xcc/0x190 fs/fcntl.c:451
 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: 0033:0x7fc9d6cbe0d9
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:00007fc9d4f16028 EFLAGS: 00000246 ORIG_RAX: 0000000000000048
RAX: ffffffffffffffda RBX: 00007fc9d6f45fa0 RCX: 00007fc9d6cbe0d9
RDX: 0000200000000280 RSI: 0000000000000026 RDI: 0000000000000004
RBP: 00007fc9d6d55024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc9d6f46038 R14: 00007fc9d6f45fa0 R15: 00007ffee84d80a8
 </TASK>