rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: (detected by 1, t=10502 jiffies, g=7933, q=27 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294961817-4294951315), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g7933 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:26080 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 schedule+0xbf/0x180 kernel/sched/core.c:6636 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 PID: 4293 Comm: syz-executor286 Not tainted 6.1.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: a1 84 f5 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e dc ae f6 48 89 df e8 f6 1a b0 f6 e8 51 6d d5 f6 fb bf 01 00 00 00 d6 9b a2 f6 65 8b 05 f7 71 46 75 85 c0 74 02 5b c3 e8 94 95 44 RSP: 0018:ffffc90003f97b30 EFLAGS: 00000286 RAX: 24315432b15a3f00 RBX: ffff888079b9a500 RCX: ffffffff973c0103 RDX: dffffc0000000000 RSI: ffffffff8b0c1d40 RDI: 0000000000000001 RBP: ffffc90003f97c70 R08: dffffc0000000000 R09: ffffed100f3734a1 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff1100f373533 R13: 000000001c000004 R14: 0000000000000021 R15: ffff888079b9a998 FS: 000055557a7c83c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 0000000077dc5000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_unlock_irq include/linux/spinlock.h:401 [inline] get_signal+0x151f/0x17a0 kernel/signal.c:2874 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd7cbf2f899 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 19 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe9d5eab08 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fd7cbf2f899 RDX: 000020000006b000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 00007fd7cbeef990 R09: 00007fd7cbeef990 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd7cbf8d33c R13: 00007fd7cbf87106 R14: 00007ffe9d5eab40 R15: 0000000000000000