rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P24397/1:b..l (detected by 0, t=10502 jiffies, g=162485, q=122) task:kworker/u4:17 state:R running task stack:22392 pid:24397 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6776 irqentry_exit+0x53/0x80 kernel/entry/common.c:426 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5626 Code: 2b 00 74 08 4c 89 f7 e8 4c e4 66 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:ffffc90003f0f8e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920007e1f28 RCX: 1ffff920007e1ec8 RDX: dffffc0000000000 RSI: ffffffff8a8b0f00 RDI: ffffffff8ad85f80 RBP: ffffc90003f0fa40 R08: dffffc0000000000 R09: fffffbfff1f79221 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920007e1f24 R13: dffffc0000000000 R14: ffffc90003f0f940 R15: 0000000000000246 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269 rcu_read_lock include/linux/rcupdate.h:696 [inline] inet_twsk_purge+0x11e/0xa20 net/ipv4/inet_timewait_sock.c:268 ops_exit_list net/core/net_namespace.c:174 [inline] cleanup_net+0x763/0xb60 net/core/net_namespace.c:596 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2307 worker_thread+0xaca/0x1280 kernel/workqueue.c:2454 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 rcu: rcu_preempt kthread timer wakeup didn't happen for 10498 jiffies! g162485 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=98969 rcu: rcu_preempt kthread starved for 10499 jiffies! g162485 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:27000 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5026 [inline] __schedule+0x12c4/0x4590 kernel/sched/core.c:6372 schedule+0x11b/0x1f0 kernel/sched/core.c:6455 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1884 rcu_gp_fqs_loop+0x2af/0xf70 kernel/rcu/tree.c:1959 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2132 kthread+0x3f6/0x4f0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 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: 2960 Comm: udevd Not tainted 5.15.115-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline] RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline] RIP: 0010:kvm_wait+0x1b4/0x200 arch/x86/kernel/kvm.c:918 Code: e0 48 c1 e8 03 42 0f b6 04 28 84 c0 75 42 45 0f b6 34 24 e8 fe 96 4e 00 44 3a 74 24 1c 75 10 66 90 0f 00 2d 3e 84 50 09 fb f4 c8 fe ff ff fb e9 c2 fe ff ff 44 89 e1 80 e1 07 38 c1 0f 8c 54 RSP: 0018:ffffc90000dd0840 EFLAGS: 00000246 RAX: 7520a8be48888a00 RBX: 1ffff920001ba10c RCX: ffffffff8162db08 RDX: dffffc0000000000 RSI: ffffffff8a8afc60 RDI: ffffffff8ad85f80 RBP: ffffc90000dd0910 R08: dffffc0000000000 R09: fffffbfff1f79239 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801dbdd8f0 R13: dffffc0000000000 R14: 0000000000000003 R15: ffffc90000dd0880 FS: 00007f4b3bc6ec80(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2228153000 CR3: 0000000020b8e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pv_wait arch/x86/include/asm/paravirt.h:597 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x6bc/0xc40 kernel/locking/qspinlock.c:508 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline] queued_spin_lock_slowpath+0x42/0x50 arch/x86/include/asm/qspinlock.h:51 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x269/0x370 kernel/locking/spinlock_debug.c:115 spin_lock include/linux/spinlock.h:363 [inline] fq_pie_timer+0x87/0x260 net/sched/sch_fq_pie.c:380 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1737 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1750 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:stack_depot_save+0x0/0x440 lib/stackdepot.c:261 Code: 48 8d 4c 18 18 49 89 0e 8b 44 18 0c eb 02 31 c0 5b 41 5e 41 5f c3 48 c7 c7 00 18 f2 8c 4c 89 fe e8 d5 5b 00 00 eb c3 0f 1f 00 <55> 41 57 41 56 41 55 41 54 53 48 83 ec 28 65 48 8b 04 25 28 00 00 RSP: 0018:ffffc90002c3f0d8 EFLAGS: 00000246 RAX: 0000000000000010 RBX: ffff88807d57a340 RCX: 7520a8be48888a00 RDX: 0000000000002800 RSI: 0000000000000010 RDI: ffffc90002c3f120 RBP: ffffc90002c3f208 R08: 000000000000000f R09: ffffc90002c3f050 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000587e20 R14: ffffc90002c3f120 R15: 1ffff1100faaf468 save_stack+0x104/0x1e0 mm/page_owner.c:120 __reset_page_owner+0x52/0x180 mm/page_owner.c:140 reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0xc34/0xcf0 mm/page_alloc.c:3317 free_unref_page+0x95/0x2d0 mm/page_alloc.c:3396 free_slab mm/slub.c:2015 [inline] discard_slab mm/slub.c:2021 [inline] __unfreeze_partials+0x1b7/0x210 mm/slub.c:2507 put_cpu_partial+0x132/0x1a0 mm/slub.c:2587 do_slab_free mm/slub.c:3487 [inline] ___cache_free+0xe3/0x100 mm/slub.c:3506 qlist_free_all+0x36/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x162/0x180 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x53/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc_trace+0xfb/0x290 mm/slub.c:3245 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] kernfs_fop_open+0x3b5/0xbc0 fs/kernfs/file.c:628 do_dentry_open+0x807/0xfb0 fs/open.c:826 do_open fs/namei.c:3538 [inline] path_openat+0x2702/0x2f20 fs/namei.c:3672 do_filp_open+0x21c/0x460 fs/namei.c:3699 do_sys_openat2+0x13b/0x500 fs/open.c:1211 do_sys_open fs/open.c:1227 [inline] __do_sys_openat fs/open.c:1243 [inline] __se_sys_openat fs/open.c:1238 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1238 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f4b3bd999a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffe9c2453e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f4b3bd999a4 RDX: 0000000000080241 RSI: 00007ffe9c245818 RDI: 00000000ffffff9c RBP: 00007ffe9c245818 R08: 0000000000000004 R09: 0000000000000001 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000080241 R13: 000055c0a9d8372e R14: 0000000000000001 R15: 0000000000000000