rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=115557, q=69 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295095325-4295084823), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g115557 f0x2 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:28824 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x125c/0x6730 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0xdd/0x2c0 kernel/sched/core.c:7326
 schedule_timeout+0x127/0x280 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1a9/0x900 kernel/rcu/tree.c:2123
 rcu_gp_kthread+0x179/0x230 kernel/rcu/tree.c:2325
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 23199 Comm: syz.2.4591 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:222 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:233 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:651 [inline]
RIP: 0010:cpu_online include/linux/cpumask.h:1233 [inline]
RIP: 0010:trace_lock_release include/trace/events/lock.h:68 [inline]
RIP: 0010:lock_release+0x38/0x310 kernel/locking/lockdep.c:5879
Code: fb 48 83 ec 18 65 48 8b 2d 7d 28 7e 12 48 89 6c 24 10 48 89 f5 0f 1f 44 00 00 65 8b 05 95 28 7e 12 83 f8 07 0f 87 07 02 00 00 <48> 0f a3 05 e0 ce 3c 0f 0f 82 02 02 00 00 44 8b 05 a7 02 3d 0f 45
RSP: 0018:ffffc90000007d50 EFLAGS: 00000097
RAX: 0000000000000000 RBX: ffffffff9b93ffa0 RCX: 0000000000000002
RDX: ffffffff9b93ff88 RSI: ffffffff85273aa4 RDI: ffffffff9b93ffa0
RBP: ffffffff85273aa4 R08: 0000000000000001 R09: fffff52000000fa4
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888032fc0300 R15: 1ffff92000000fb8
FS:  00007f0c8e4166c0(0000) GS:ffff888123de6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3361aff8 CR3: 000000009b619000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000001800
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_irqrestore+0x1a/0x80 kernel/locking/spinlock.c:198
 debug_object_deactivate+0x2e4/0x3b0 lib/debugobjects.c:951
 debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
 __run_hrtimer kernel/time/hrtimer.c:2000 [inline]
 __hrtimer_run_queues+0x2e9/0x9c0 kernel/time/hrtimer.c:2096
 hrtimer_interrupt+0x3e5/0x940 kernel/time/hrtimer.c:2215
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x109/0x470 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x9e/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:lock_release+0x19e/0x310 kernel/locking/lockdep.c:5893
Code: ff 65 0f c1 05 e3 6d 7e 12 83 f8 01 0f 85 27 01 00 00 9c 58 f6 c4 02 0f 85 12 01 00 00 41 f7 c6 00 02 00 00 0f 85 c8 00 00 00 <48> 8b 44 24 10 65 48 2b 05 ed 26 7e 12 0f 85 4d 01 00 00 48 83 c4
RSP: 0018:ffffc90006f4fc58 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffff8880751103b8 RCX: ffffc90006f4fc64
RDX: 0000000000000000 RSI: ffffffff8e17ea6e RDI: ffffffff8c401380
RBP: ffffffff825d38e5 R08: 0000000000000001 R09: 00000000000001c8
R10: 0000000000000200 R11: 0000000000000000 R12: ffff88801e6d2540
R13: ffffffff825d38e5 R14: 0000000000000283 R15: 0000000000000001
 __might_fault+0x10c/0x140 mm/memory.c:7292
 do_recvmmsg+0x31c/0x740 net/socket.c:3047
 __sys_recvmmsg net/socket.c:3115 [inline]
 __do_sys_recvmmsg net/socket.c:3138 [inline]
 __se_sys_recvmmsg net/socket.c:3131 [inline]
 __x64_sys_recvmmsg+0x22a/0x280 net/socket.c:3131
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0c8d59de99
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:00007f0c8e416028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007f0c8d826090 RCX: 00007f0c8d59de99
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007f0c8d633eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0c8d826128 R14: 00007f0c8d826090 R15: 00007ffcb32f5db8
 </TASK>