rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5832/1:b..l rcu: (detected by 1, t=10503 jiffies, g=28173, q=776 ncpus=2) task:syz-executor state:R running task stack:19952 pid:5832 tgid:5832 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5371 [inline] __schedule+0x189f/0x4c80 kernel/sched/core.c:6758 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7080 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:unwind_get_return_address+0x56/0x90 arch/x86/kernel/unwind_orc.c:369 Code: 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 cb 11 ba 00 48 8b 3b e8 23 67 1e 00 85 c0 74 14 43 80 3c 37 00 <74> 08 48 89 df e8 b0 11 ba 00 48 8b 03 eb 02 31 c0 5b 41 5e 41 5f RSP: 0018:ffffc90003f2f500 EFLAGS: 00000246 RAX: 0000000000000001 RBX: ffffc90003f2f568 RCX: ffffffff917ab000 RDX: ffffffff9195b901 RSI: ffffc90003f28000 RDI: ffffffff8180dd6f RBP: ffffc90003f2f5b0 R08: ffffc90003f2fab0 R09: 0000000000000000 R10: ffffc90003f2f570 R11: fffff520007e5eb0 R12: ffff88802b19bc00 R13: ffffffff81aae620 R14: dffffc0000000000 R15: 1ffff920007e5ead arch_stack_walk+0xfd/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 save_stack+0xfb/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x76/0x430 mm/page_owner.c:297 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2660 vfree+0x1c3/0x360 mm/vmalloc.c:3383 kcov_put kernel/kcov.c:439 [inline] kcov_close+0x28/0x50 kernel/kcov.c:535 __fput+0x3e9/0x9f0 fs/file_table.c:450 task_work_run+0x24f/0x310 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xa2f/0x28e0 kernel/exit.c:938 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3017 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0e6198473c RSP: 002b:00007ffc80205270 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00007f0e6198473c RDX: 0000000000000030 RSI: 00007ffc80205320 RDI: 00000000000000f9 RBP: 00007ffc802052cc R08: 0000000000000000 R09: 0079746972756365 R10: 00007f0e61b487e0 R11: 0000000000000246 R12: 0000000000000063 R13: 00000000000426a8 R14: 00007ffc80205320 R15: 0000000000000087 rcu: rcu_preempt kthread starved for 2749 jiffies! g28173 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:25912 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5371 [inline] __schedule+0x189f/0x4c80 kernel/sched/core.c:6758 __schedule_loop kernel/sched/core.c:6835 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6850 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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: 8 Comm: kworker/0:0 Not tainted 6.13.0-rc3-next-20241220-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_power_efficient neigh_periodic_work RIP: 0010:ether_addr_equal_64bits include/linux/etherdevice.h:389 [inline] RIP: 0010:eth_skb_pkt_type include/linux/etherdevice.h:627 [inline] RIP: 0010:eth_type_trans+0x300/0x7b0 net/ethernet/eth.c:165 Code: c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 98 19 4b f8 49 8b 1e 4c 31 e3 49 bf ff ff ff ff ff ff 00 00 48 89 de 4c 21 fe 31 ff db a2 e4 f7 4c 21 fb 0f 85 25 01 00 00 e8 ed 9d e4 f7 4c 8b 7c RSP: 0018:ffffc90000007320 EFLAGS: 00000246 RAX: 1ffff1100bb1c505 RBX: aaaa000000000000 RCX: ffff88801ce85a00 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000007408 R08: ffffffff89da8575 R09: ffffffff89bb6ea3 R10: 0000000000000003 R11: ffffffff86a37c50 R12: aaaa0aaaaaaaaaaa R13: dffffc0000000000 R14: ffff88805d8e2828 R15: 0000ffffffffffff FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f08f3d75f40 CR3: 0000000021770000 CR4: 00000000003526f0 DR0: fffffffffffffffc DR1: 0000000080000000 DR2: 0008000000000001 DR3: fffffffffffffffc DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: loopback_xmit+0x40b/0x6b0 drivers/net/loopback.c:86 __netdev_start_xmit include/linux/netdevice.h:5049 [inline] netdev_start_xmit include/linux/netdevice.h:5058 [inline] generic_xdp_tx+0x198/0x3b0 net/core/dev.c:5124 do_xdp_generic+0x952/0xd30 net/core/dev.c:5158 __netif_receive_skb_core+0x1ce9/0x4690 net/core/dev.c:5492 __netif_receive_skb_one_core net/core/dev.c:5670 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5785 process_backlog+0x662/0x15b0 net/core/dev.c:6117 __napi_poll+0xcb/0x490 net/core/dev.c:6883 napi_poll net/core/dev.c:6952 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7074 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 do_softirq+0x11b/0x1e0 kernel/softirq.c:462 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:389 neigh_periodic_work+0xbcb/0xde0 net/core/neighbour.c:968 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244