rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P2/1:b..l rcu: (detected by 1, t=10503 jiffies, g=7913, q=1489730 ncpus=2) task:kthreadd state:R running task stack:24176 pid:2 tgid:2 ppid:0 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7004 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:stack_trace_consume_entry+0x6a/0x280 kernel/stacktrace.c:89 Code: 89 ec 49 c1 ec 03 41 0f b6 04 14 84 c0 0f 85 1a 01 00 00 44 3b 45 00 73 3c 48 8d 7b 0c 49 89 fd 49 c1 ed 03 41 0f b6 44 15 00 <84> c0 0f 85 36 01 00 00 44 8b 37 45 85 f6 74 22 41 ff ce 41 0f b6 RSP: 0018:ffffc90000077350 EFLAGS: 00000a03 RAX: 0000000000000000 RBX: ffffc90000077480 RCX: ffffffff917be000 RDX: dffffc0000000000 RSI: ffffffff81604dbd RDI: ffffc9000007748c RBP: ffffc90000077488 R08: 000000000000000c R09: ffffc90000077490 R10: ffffc900000773f0 R11: ffffffff8180a0e0 R12: 1ffff9200000ee91 R13: 1ffff9200000ee91 R14: ffffc90000077480 R15: 1ffff9200000ee92 arch_stack_walk+0x10e/0x150 arch/x86/kernel/stacktrace.c:27 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:1108 [inline] free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638 discard_slab mm/slub.c:2677 [inline] __put_partials+0xeb/0x130 mm/slub.c:3145 put_cpu_partial+0x17c/0x250 mm/slub.c:3220 __slab_free+0x2ea/0x3d0 mm/slub.c:4449 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141 copy_sighand+0x50/0x230 kernel/fork.c:1793 copy_process+0x1793/0x3d50 kernel/fork.c:2366 kernel_clone+0x226/0x8f0 kernel/fork.c:2784 kernel_thread+0x1bc/0x240 kernel/fork.c:2846 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:767 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 10542 jiffies! g7913 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:25136 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2615 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 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: 5275 Comm: kworker/0:4 Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:979 [inline] RIP: 0010:debug_check_no_obj_freed+0x2be/0x580 lib/debugobjects.c:1019 Code: ff c7 48 8b 44 24 38 48 85 c0 0f 84 a4 02 00 00 49 89 c4 49 89 c5 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 <74> 08 4c 89 e7 e8 78 03 3c fd 49 8b 04 24 48 89 44 24 38 49 8d 5c RSP: 0018:ffffc90000006fe0 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff88818d993e88 RCX: dffffc0000000000 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90000006ec0 RBP: ffffc90000007140 R08: 0000000000000003 R09: fffff52000000dd8 R10: dffffc0000000000 R11: fffff52000000dd8 R12: ffff88818eef3e38 R13: 1ffff11031dde7c7 R14: ffff88818d99a650 R15: 000000000000000a FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055557898d5c8 CR3: 00000000633c6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: slab_free_hook mm/slub.c:2273 [inline] slab_free mm/slub.c:4579 [inline] kfree+0x11f/0x440 mm/slub.c:4727 skb_kfree_head net/core/skbuff.c:1086 [inline] skb_free_head net/core/skbuff.c:1098 [inline] skb_release_data+0x6a0/0x8a0 net/core/skbuff.c:1125 skb_release_all net/core/skbuff.c:1190 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] consume_skb+0x9f/0xf0 net/core/skbuff.c:1436 nft_synproxy_do_eval+0x746/0xa60 net/netfilter/nft_synproxy.c:145 expr_call_ops_eval net/netfilter/nf_tables_core.c:240 [inline] nft_do_chain+0x4ad/0x1da0 net/netfilter/nf_tables_core.c:288 nft_do_chain_inet+0x418/0x6b0 net/netfilter/nft_chain_filter.c:161 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5668 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5781 process_backlog+0x662/0x15b0 net/core/dev.c:6113 __napi_poll+0xcb/0x490 net/core/dev.c:6834 napi_poll net/core/dev.c:6903 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7025 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x75d/0xaa0 drivers/net/netdevsim/dev.c:850 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244