rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=562c/1/0x4000000000000000 softirq=74051/74052 fqs=60 (detected by 0, t=10502 jiffies, g=100745, q=229 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9984 Comm: syz-executor.0 Not tainted 6.1.55-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 RIP: 0010:validate_chain+0x66/0x58e0 kernel/locking/lockdep.c:3780 Code: 00 00 00 fc ff df 48 c7 84 24 00 01 00 00 b3 8a b5 41 48 c7 84 24 08 01 00 00 f3 55 96 8c 48 c7 84 24 10 01 00 00 e0 f2 6a 81 <48> 8d 8c 24 00 01 00 00 48 c1 e9 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 RSP: 0018:ffffc900001e0740 EFLAGS: 00000082 RAX: 0741c0624eb6bf00 RBX: ffffffff9018d160 RCX: 7aa5547729421dfb RDX: 0000000000000000 RSI: ffff8880826de470 RDI: ffff8880826dd940 RBP: ffffc900001e09f0 R08: dffffc0000000000 R09: fffffbfff2092e45 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff8880826dd940 R14: 7aa5547729421dfb R15: 1ffff110104dbc92 FS: 0000555556b59480(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f073cb98000 CR3: 000000007af6a000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5048 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5661 __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+0x61/0x420 lib/debugobjects.c:772 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate+0x1d/0x280 kernel/time/hrtimer.c:481 __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x334/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 12 95 4e f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 47 2c cb f6 65 8b 05 28 6e 6f 75 85 c0 74 3f 48 c7 04 24 0e 36 RSP: 0018:ffffc9000313f0a0 EFLAGS: 00000206 RAX: 0741c0624eb6bf00 RBX: 1ffff92000627e18 RCX: ffffffff816aa7ba RDX: dffffc0000000000 RSI: ffffffff8aebe2a0 RDI: 0000000000000001 RBP: ffffc9000313f130 R08: dffffc0000000000 R09: fffffbfff2092e55 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000627e14 R14: ffffc9000313f0c0 R15: 0000000000000246 kfence_guarded_alloc+0x1fb/0xe40 mm/kfence/core.c:373 __kfence_alloc+0x340/0x370 mm/kfence/core.c:1044 kfence_alloc include/linux/kfence.h:128 [inline] slab_alloc_node mm/slub.c:3322 [inline] __kmem_cache_alloc_node+0x1fa/0x260 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:954 [inline] __kmalloc_node+0xa2/0x230 mm/slab_common.c:962 kmalloc_node include/linux/slab.h:579 [inline] __vmalloc_area_node mm/vmalloc.c:3037 [inline] __vmalloc_node_range+0x5c0/0x1460 mm/vmalloc.c:3223 __vmalloc_node mm/vmalloc.c:3288 [inline] vzalloc+0x75/0x80 mm/vmalloc.c:3361 alloc_counters+0xd0/0x7b0 net/ipv4/netfilter/ip_tables.c:801 copy_entries_to_user net/ipv4/netfilter/ip_tables.c:823 [inline] get_entries net/ipv4/netfilter/ip_tables.c:1024 [inline] do_ipt_get_ctl+0xeb1/0x1890 net/ipv4/netfilter/ip_tables.c:1662 nf_getsockopt+0x28e/0x2b0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x21a/0x2d0 net/ipv4/ip_sockglue.c:1824 tcp_getsockopt+0x15c/0x1c0 net/ipv4/tcp.c:4406 __sys_getsockopt+0x2b2/0x5d0 net/socket.c:2296 __do_sys_getsockopt net/socket.c:2311 [inline] __se_sys_getsockopt net/socket.c:2308 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2308 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+0x63/0xcd RIP: 0033:0x7f6b9167e68a Code: c4 c1 e0 1a 0d 00 00 04 00 89 01 e9 e0 fe ff ff e8 3b 05 00 00 66 2e 0f 1f 84 00 00 00 00 00 90 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 b0 ff ff ff f7 RSP: 002b:00007ffebb8078a8 EFLAGS: 00000216 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00007ffebb807930 RCX: 00007f6b9167e68a RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007ffebb8078cc R09: 0079746972756365 R10: 00007ffebb807930 R11: 0000000000000216 R12: 00007f6b9177a800 R13: 00007ffebb8078cc R14: 0000000000000000 R15: 00007f6b9177aec0 rcu: rcu_preempt kthread starved for 10382 jiffies! g100745 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:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6554 schedule+0xbf/0x180 kernel/sched/core.c:6630 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x2c2/0x1010 kernel/rcu/tree.c:1661 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1860 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 13714 Comm: kworker/0:22 Not tainted 6.1.55-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Workqueue: events fqdir_free_fn RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline] RIP: 0010:smp_call_function_single+0x4a3/0x2610 kernel/smp.c:776 Code: b6 04 23 84 c0 0f 85 70 01 00 00 45 8b 2e 44 89 ee 83 e6 01 31 ff e8 4c 7f 0b 00 41 83 e5 01 75 07 e8 e1 7b 0b 00 eb 3e f3 90 <42> 0f b6 04 23 84 c0 75 10 41 f7 06 01 00 00 00 74 25 e8 c6 7b 0b RSP: 0018:ffffc90005587820 EFLAGS: 00000293 RAX: ffffffff817ef74a RBX: 1ffff92000ab0f21 RCX: ffff888076c11dc0 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc90005587ba0 R08: ffffffff817ef724 R09: fffff52000ab0ecd R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000001 R14: ffffc90005587908 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c026a27f10 CR3: 0000000089d2e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_barrier+0x323/0x5f0 kernel/rcu/tree.c:4017 fqdir_free_fn+0x2e/0x130 net/ipv4/inet_fragment.c:163 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:306