rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P51/1:b..l P3622/1:b..l (detected by 0, t=10506 jiffies, g=20745, q=96 ncpus=2) task:udevd state:R running task stack:22600 pid:3622 ppid:1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6727 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6751 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock kernel/sched/wait.c:140 [inline] __wake_up_sync_key+0x121/0x1c0 kernel/sched/wait.c:208 sock_def_readable+0x15b/0x280 net/core/sock.c:3305 __netlink_sendskb net/netlink/af_netlink.c:1258 [inline] netlink_sendskb+0x8e/0x120 net/netlink/af_netlink.c:1264 netlink_unicast+0x394/0x970 net/netlink/af_netlink.c:1352 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1859 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5a5/0x8f0 net/socket.c:2519 ___sys_sendmsg net/socket.c:2573 [inline] __sys_sendmsg+0x2a9/0x390 net/socket.c:2602 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5976d24a4b RSP: 002b:00007ffdd7ec33f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000564c59a2f9e0 RCX: 00007f5976d24a4b RDX: 0000000000000000 RSI: 00007ffdd7ec3408 RDI: 0000000000000004 RBP: 0000564c59a54ec0 R08: 0000000000000001 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000000b3 R14: 0000000000000000 R15: 0000000000000000 task:kworker/u4:3 state:R running task stack:22232 pid:51 ppid:2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 preempt_schedule_notrace+0xf8/0x140 kernel/sched/core.c:6820 preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 rcu_is_watching+0x76/0xb0 kernel/rcu/tree.c:722 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xfa/0x5a0 kernel/locking/lockdep.c:5633 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] net_generic include/net/netns/generic.h:45 [inline] nf_frag_pernet+0x40/0x230 net/ipv6/netfilter/nf_conntrack_reasm.c:41 nf_ct_net_exit+0x23/0xc0 net/ipv6/netfilter/nf_conntrack_reasm.c:525 ops_exit_list net/core/net_namespace.c:172 [inline] cleanup_net+0x6ce/0xb60 net/core/net_namespace.c:604 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g20745 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=9343 rcu: rcu_preempt kthread starved for 10506 jiffies! g20745 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26720 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6023 Comm: dhcpcd-run-hook Not tainted 6.1.119-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:lock_acquire+0x225/0x5a0 kernel/locking/lockdep.c:5665 Code: 20 48 c7 c7 40 13 0c 8b e8 98 49 47 09 b8 ff ff ff ff 65 0f c1 05 9b d5 97 7e 83 f8 01 0f 85 a4 01 00 00 49 89 de 48 c1 eb 03 <42> 80 3c 2b 00 74 08 4c 89 f7 e8 4c 82 77 00 48 c7 44 24 60 00 00 RSP: 0018:ffffc900001e0ae0 EFLAGS: 00000802 RAX: 0000000000000001 RBX: 1ffff9200003c168 RCX: ffffffff816b5e82 RDX: dffffc0000000000 RSI: ffffffff8b0c1340 RDI: ffffffff8b5e6200 RBP: ffffc900001e0c28 R08: dffffc0000000000 R09: fffffbfff224984d R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200003c164 R13: dffffc0000000000 R14: ffffc900001e0b40 R15: 0000000000000046 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2dc1dff8 CR3: 0000000044698000 CR4: 00000000003506e0 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 debug_object_deactivate+0x63/0x380 lib/debugobjects.c:753 debug_hrtimer_deactivate kernel/time/hrtimer.c:426 [inline] debug_deactivate+0x1d/0x280 kernel/time/hrtimer.c:482 __run_hrtimer kernel/time/hrtimer.c:1657 [inline] __hrtimer_run_queues+0x334/0xe50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x158/0x5b0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 af 81 77 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003f57a00 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007eaf4c RCX: 1ffff920007eaeec RDX: dffffc0000000000 RSI: ffffffff8b0c1340 RDI: ffffffff8b5e6200 RBP: ffffc90003f57b50 R08: dffffc0000000000 R09: fffffbfff224984d R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920007eaf48 R13: dffffc0000000000 R14: ffffc90003f57a60 R15: 0000000000000246 __raw_spin_trylock include/linux/spinlock_api_smp.h:90 [inline] _raw_spin_trylock+0x42/0x70 kernel/locking/spinlock.c:138 spin_trylock include/linux/spinlock.h:361 [inline] free_unref_page+0x156/0x3e0 mm/page_alloc.c:3485 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] slab_alloc mm/slub.c:3406 [inline] __kmem_cache_alloc_lru mm/slub.c:3413 [inline] kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422 getname_flags+0xb8/0x4f0 fs/namei.c:139 vfs_fstatat fs/stat.c:266 [inline] __do_sys_newfstatat fs/stat.c:437 [inline] __se_sys_newfstatat fs/stat.c:431 [inline] __x64_sys_newfstatat+0x130/0x1e0 fs/stat.c:431 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb1bdde88a9 Code: 49 01 00 09 00 00 00 83 c8 ff c3 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 00 00 00 00 41 89 ca b8 06 01 00 00 0f 05 <45> 31 c0 3d 00 f0 ff ff 76 0c f7 d8 41 83 c8 ff 89 05 a1 49 01 00 RSP: 002b:00007ffe01bfcdc8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 00007fb1bddcb000 RCX: 00007fb1bdde88a9 RDX: 00007ffe01bfce70 RSI: 00007ffe01bfcdd0 RDI: 00000000ffffff9c RBP: 00007ffe01bfcf30 R08: 0000000000080000 R09: 00007ffe01bfcdd0 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe01bfcdd0 R13: 0000000000000008 R14: 00007fb1bddfaa40 R15: 00000000ffffffff