rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=b1b/1/0x4000000000000000 softirq=15216/15216 fqs=27 (detected by 0, t=10506 jiffies, g=20193, q=622) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1514 Comm: kworker/u4:4 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: netns cleanup_net RIP: 0010:debug_smp_processor_id+0xe/0x10 lib/smp_processor_id.c:60 Code: 00 00 00 00 48 c7 c7 60 dc 12 8a e8 2c 01 00 00 65 ff 0d 21 5d 61 76 5b c3 00 00 cc 48 c7 c7 a0 e7 59 8a 48 c7 c6 e0 e7 59 8a 00 55 41 57 41 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 RSP: 0018:ffffc90000dd0cc0 EFLAGS: 00000082 RAX: ffffffff8167e7d3 RBX: ffff88805f0c2340 RCX: ffff888023b5d940 RDX: 0000000000010000 RSI: ffffffff8a59e7e0 RDI: ffffffff8a59e7a0 RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ad26b6 R10: fffffbfff1ad26b6 R11: 1ffffffff1ad26b5 R12: dffffc0000000000 R13: 0000000000000001 R14: ffff8880b912a440 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7d32967000 CR3: 0000000029c86000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline] rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123 trace_hrtimer_start include/trace/events/timer.h:199 [inline] debug_activate kernel/time/hrtimer.c:466 [inline] enqueue_hrtimer+0x9d/0x370 kernel/time/hrtimer.c:1069 __run_hrtimer kernel/time/hrtimer.c:1702 [inline] __hrtimer_run_queues+0x65a/0xc40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:lock_release+0x584/0x870 kernel/locking/lockdep.c:5647 Code: 00 00 00 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 75 75 f7 44 24 50 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 2f 00 00 00 00 66 43 c7 44 2f 09 00 00 43 c6 44 2f 0b 00 RSP: 0018:ffffc90006707920 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 977d001d80a4098d RCX: 663f113de2203600 RDX: 0000000000000003 RSI: ffffffff8a0b2e80 RDI: ffffffff8a59e800 RBP: ffffc90006707a30 R08: dffffc0000000000 R09: fffffbfff1ad26b6 R10: fffffbfff1ad26b6 R11: 1ffffffff1ad26b5 R12: ffff888023b5e4a8 R13: dffffc0000000000 R14: ffff888023b5e420 R15: 1ffff92000ce0f30 rcu_read_unlock include/linux/rcupdate.h:773 [inline] inet_twsk_purge+0x77d/0x810 net/ipv4/inet_timewait_sock.c:309 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x77b/0xb80 net/core/net_namespace.c:635 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread starved for 10370 jiffies! g20193 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:27880 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 0 CPU: 0 PID: 6603 Comm: syz.4.791 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline] rcu_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3936 [inline] rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:1818 tick_sched_handle kernel/time/tick-sched.c:254 [inline] tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline] RIP: 0010:smp_call_function_many_cond+0xb88/0xd70 kernel/smp.c:969 Code: b6 44 05 00 84 c0 0f 85 9d 00 00 00 41 8b 1c 24 89 de 83 e6 01 31 ff e8 66 49 0b 00 83 e3 01 75 07 e8 fc 45 0b 00 eb 43 f3 90 <48> b8 00 00 00 00 00 fc ff df 41 0f b6 44 05 00 84 c0 75 11 41 f7 RSP: 0018:ffffc90003b7f300 EFLAGS: 00000246 RAX: ffffffff816c863b RBX: 0000000000000001 RCX: 0000000000080000 RDX: ffffc9000568a000 RSI: 000000000007ffff RDI: 0000000000080000 RBP: ffffc90003b7f440 R08: dffffc0000000000 R09: fffffbfff1ff541a R10: fffffbfff1ff541a R11: 1ffffffff1ff5419 R12: ffff8880b91405c8 R13: 1ffff110172280b9 R14: ffff8880b903b3c0 R15: 0000000000000001 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1134 __purge_vmap_area_lazy+0x216/0x18f0 mm/vmalloc.c:1690 _vm_unmap_aliases+0x410/0x4a0 mm/vmalloc.c:2114 change_page_attr_set_clr+0x311/0xc10 arch/x86/mm/pat/set_memory.c:1740 change_page_attr_clear arch/x86/mm/pat/set_memory.c:1797 [inline] set_memory_ro+0x89/0xd0 arch/x86/mm/pat/set_memory.c:1943 bpf_jit_binary_lock_ro include/linux/filter.h:919 [inline] bpf_int_jit_compile+0xc4af/0xcc80 arch/x86/net/bpf_jit_comp.c:2478 bpf_prog_select_runtime+0x46f/0x7c0 kernel/bpf/core.c:1977 bpf_migrate_filter net/core/filter.c:1307 [inline] bpf_prepare_filter+0x1014/0x11c0 net/core/filter.c:1355 bpf_prog_create_from_user+0x2ce/0x420 net/core/filter.c:1449 seccomp_prepare_filter kernel/seccomp.c:669 [inline] seccomp_prepare_user_filter kernel/seccomp.c:706 [inline] seccomp_set_mode_filter kernel/seccomp.c:1834 [inline] do_seccomp+0x7b6/0x1630 kernel/seccomp.c:1954 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f7d3c995749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7d3abfc038 EFLAGS: 00000246 ORIG_RAX: 000000000000013d RAX: ffffffffffffffda RBX: 00007f7d3cbebfa0 RCX: 00007f7d3c995749 RDX: 0000200000000040 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 00007f7d3ca19f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f7d3cbec038 R14: 00007f7d3cbebfa0 R15: 00007ffc3b0bf338