rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=7233, q=1933702 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 8457 (4294958716-4294950259), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 8457 jiffies! g7233 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:25912 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6767 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: 5232 Comm: kworker/0:3 Not tainted 6.12.0-rc1-syzkaller-00280-g489cee4caeba #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:lookup_object lib/debugobjects.c:195 [inline] RIP: 0010:debug_object_deactivate+0x19a/0x390 lib/debugobjects.c:765 Code: 43 3c fd 4c 89 3c 24 48 8b 1b 45 31 ff eb 06 48 8b 1b 41 ff c7 48 85 db 74 38 4c 8d 63 18 4c 89 e0 48 c1 e8 03 42 80 3c 30 00 <74> 08 4c 89 e7 e8 ec 42 3c fd 4d 39 2c 24 74 2e 48 89 d8 48 c1 e8 RSP: 0018:ffffc900000060a0 EFLAGS: 00000046 RAX: 1ffff11012680a03 RBX: ffff888093405000 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffffc90000005f80 RBP: ffffc90000006190 R08: 0000000000000003 R09: fffff52000000bf0 R10: dffffc0000000000 R11: fffff52000000bf0 R12: ffff888093405018 R13: ffff8880b862d198 R14: dffffc0000000000 R15: 0000000000000081 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd54f9ff3e0 CR3: 0000000063044000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: debug_hrtimer_deactivate kernel/time/hrtimer.c:428 [inline] debug_deactivate+0x1b/0x220 kernel/time/hrtimer.c:484 __run_hrtimer kernel/time/hrtimer.c:1659 [inline] __hrtimer_run_queues+0x305/0xd50 kernel/time/hrtimer.c:1755 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1817 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1026 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 arch/x86/kernel/apic/apic.c:1043 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1037 [inline] sysvec_apic_timer_interrupt+0x52/0xc0 arch/x86/kernel/apic/apic.c:1037 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:58 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] RIP: 0010:unwind_next_frame+0xb98/0x22d0 arch/x86/kernel/unwind_orc.c:585 Code: c1 ef 03 43 80 3c 27 00 74 08 48 89 df e8 40 2b bd 00 4c 8b 74 24 08 4d 8b 66 10 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 20 <0f> b6 04 01 84 c0 0f 85 67 12 00 00 48 8b 04 24 4c 8d 68 f8 41 83 RSP: 0018:ffffc90000006530 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffc90000006610 RCX: 1ffff92000000cc0 RDX: ffffffff9128defe RSI: 0000000000000002 RDI: 0000000000000001 RBP: ffffc90000000000 R08: 0000000000000003 R09: ffffc900000066f0 R10: ffffc90000006650 R11: ffffffff81808f50 R12: ffffc90000008000 R13: ffffc90000006600 R14: ffffc90000006600 R15: 1ffff92000000cc2 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:257 [inline] __kmalloc_cache_noprof+0x19c/0x2c0 mm/slub.c:4296 kmalloc_noprof include/linux/slab.h:878 [inline] kzalloc_noprof include/linux/slab.h:1014 [inline] ref_tracker_alloc+0x14b/0x490 lib/ref_tracker.c:203 __netdev_tracker_alloc include/linux/netdevice.h:4057 [inline] netdev_hold include/linux/netdevice.h:4086 [inline] dst_init+0xee/0x490 net/core/dst.c:52 dst_alloc+0x14f/0x190 net/core/dst.c:93 rt_dst_alloc net/ipv4/route.c:1612 [inline] __mkroute_output net/ipv4/route.c:2577 [inline] ip_route_output_key_hash_rcu+0x13cc/0x2390 net/ipv4/route.c:2799 ip_route_output_key_hash+0x193/0x2b0 net/ipv4/route.c:2628 __ip_route_output_key include/net/route.h:141 [inline] ip_route_output_flow+0x29/0x140 net/ipv4/route.c:2856 ip_route_output_key include/net/route.h:151 [inline] ip_route_me_harder+0x80d/0x1300 net/ipv4/netfilter.c:53 synproxy_send_tcp+0x356/0x6c0 net/netfilter/nf_synproxy_core.c:431 synproxy_send_client_synack+0x8b8/0xf30 net/netfilter/nf_synproxy_core.c:484 nft_synproxy_eval_v4+0x3ca/0x610 net/netfilter/nft_synproxy.c:59 nft_synproxy_do_eval+0x362/0xa60 net/netfilter/nft_synproxy.c:141 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:5666 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5779 process_backlog+0x662/0x15b0 net/core/dev.c:6111 __napi_poll+0xcb/0x490 net/core/dev.c:6775 napi_poll net/core/dev.c:6844 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6966 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