rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=13938 jiffies, g=174401, q=934 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 13938 (4295069281-4295055343), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 13938 jiffies! g174401 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:26568 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 schedule_timeout+0x1bd/0x310 kernel/time/timer.c:2167 rcu_gp_fqs_loop+0x2c6/0x1010 kernel/rcu/tree.c:1609 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1808 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 15380 Comm: kworker/1:0 Not tainted 6.5.0-rc2-syzkaller-00052-gbfa3037d8280 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023 Workqueue: events_power_efficient gc_worker RIP: 0010:lock_is_held_type+0x95/0x190 kernel/locking/lockdep.c:5832 Code: 24 24 fa 48 c7 c7 20 9d 0a 8b e8 36 17 00 00 65 ff 05 e7 03 46 75 41 83 bd c0 0a 00 00 00 7e 47 4c 89 ed 48 81 c5 c8 0a 00 00 <31> db 48 83 fb 31 73 24 48 89 ef 4c 89 fe e8 28 02 00 00 85 c0 75 RSP: 0018:ffffc900001e0628 EFLAGS: 00000086 RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffff888021b49dc0 RDX: ffff888021b49dc0 RSI: ffffffff8b0a9d20 RDI: ffffffff8b58a540 RBP: ffff888021b4a888 R08: ffffffff88dcbf4e R09: fffff5200003c0bc R10: dffffc0000000000 R11: fffff5200003c0bc R12: 0000000000000046 R13: ffff888021b49dc0 R14: 00000000ffffffff R15: ffff8880773c1300 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9b9539609c CR3: 000000000d130000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:288 [inline] advance_sched+0xd0/0xc80 net/sched/sch_taprio.c:936 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x59f/0xd10 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x396/0x980 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1098 [inline] __sysvec_apic_timer_interrupt+0x13f/0x480 arch/x86/kernel/apic/apic.c:1115 sysvec_apic_timer_interrupt+0x42/0xb0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] RIP: 0010:kvm_wait+0x1c0/0x200 arch/x86/kernel/kvm.c:1060 Code: 03 42 0f b6 04 28 84 c0 75 46 45 0f b6 34 24 e8 96 6f 56 00 44 3a 74 24 1c 75 14 66 90 0f 00 2d 96 c1 cb 09 f3 0f 1e fa fb f4 c0 fe ff ff fb e9 ba fe ff ff 44 89 e1 80 e1 07 38 c1 0f 8c 4c RSP: 0018:ffffc900001e0aa0 EFLAGS: 00000246 RAX: ab4bfae4330e1400 RBX: 1ffff9200003c158 RCX: ffffffff816c2c6a RDX: dffffc0000000000 RSI: ffffffff8b0a9040 RDI: ffffffff8b58a540 RBP: ffffc900001e0b70 R08: ffffffff907b13c7 R09: 1ffffffff20f6278 R10: dffffc0000000000 R11: fffffbfff20f6279 R12: ffff8880773c10f0 R13: dffffc0000000000 R14: 0000000000000003 R15: ffffc900001e0ae0 pv_wait arch/x86/include/asm/paravirt.h:598 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x6ff/0xc50 kernel/locking/qspinlock.c:511 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:586 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x297/0x3a0 kernel/locking/spinlock_debug.c:115 spin_lock include/linux/spinlock.h:351 [inline] net_tx_action+0x7d7/0xa00 net/core/dev.c:5033 __do_softirq+0x2ab/0x908 kernel/softirq.c:553 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu+0xf1/0x1b0 kernel/softirq.c:632 irq_exit_rcu+0x9/0x20 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1109 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:seqcount_lockdep_reader_access+0x1e0/0x220 include/linux/seqlock.h:105 Code: f8 4d 85 ed 75 16 e8 cf 64 9f f8 eb 15 e8 c8 64 9f f8 e8 53 e1 cf 01 4d 85 ed 74 ea e8 b9 64 9f f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00 RSP: 0018:ffffc9000eabfa00 EFLAGS: 00000293 RAX: ffffffff88eca0d7 RBX: 0000000000000000 RCX: ffff888021b49dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000eabfab0 R08: ffffffff88eca0ad R09: 1ffffffff20f6271 R10: dffffc0000000000 R11: fffffbfff20f6272 R12: dffffc0000000000 R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff92001d57f40 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:343 [inline] gc_worker+0x306/0x1580 net/netfilter/nf_conntrack_core.c:1490 process_one_work+0x92c/0x12c0 kernel/workqueue.c:2597 worker_thread+0xa63/0x1210 kernel/workqueue.c:2748 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:296 RIP: 0000:0x0 Code: Unable to access opcode bytes at 0xffffffffffffffd6. RSP: 0000:0000000000000000 EFLAGS: 00000000 ORIG_RAX: 0000000000000000 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000